maintenance/tables.sql - mediawiki/core - Gitiles

 -- SQL to create the initial tables for the MediaWiki database.
 -- This is read and executed by the install script; you should
 -- not have to run it by itself unless doing a manual install.

 -- This is a shared schema file used for both MySQL and SQLite installs.
 --
 -- For more documentation on the database schema, see
 -- https://www.mediawiki.org/wiki/Manual:Database_layout
 --
 -- General notes:
 --
 -- If possible, create tables as InnoDB to benefit from the
 -- superior resiliency against crashes and ability to read
 -- during writes (and write during reads!)
 --
 -- Only the 'searchindex' table requires MyISAM due to the
 -- requirement for fulltext index support, which is missing
 -- from InnoDB.
 --
 --
 -- The MySQL table backend for MediaWiki currently uses
 -- 14-character BINARY or VARBINARY fields to store timestamps.
 -- The format is YYYYMMDDHHMMSS, which is derived from the
 -- text format of MySQL's TIMESTAMP fields.
 --
 -- Historically TIMESTAMP fields were used, but abandoned
 -- in early 2002 after a lot of trouble with the fields
 -- auto-updating.
 --
 -- The Postgres backend uses TIMESTAMPTZ fields for timestamps,
 -- and we will migrate the MySQL definitions at some point as
 -- well.
 --
 --
 -- The /*_*/ comments in this and other files are
 -- replaced with the defined table prefix by the installer
 -- and updater scripts. If you are installing or running
 -- updates manually, you will need to manually insert the
 -- table prefix if any when running these scripts.
 --


 --
 -- The user table contains basic account information,
 -- authentication keys, etc.
 --
 -- Some multi-wiki sites may share a single central user table
 -- between separate wikis using the $wgSharedDB setting.
 --
 -- Note that when a external authentication plugin is used,
 -- user table entries still need to be created to store
 -- preferences and to key tracking information in the other
 -- tables.
 --
 CREATE TABLE /*_*/user (
   user_id int unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,

   -- Usernames must be unique, must not be in the form of
   -- an IP address. _Shouldn't_ allow slashes or case
   -- conflicts. Spaces are allowed, and are _not_ converted
   -- to underscores like titles. See the User::newFromName() for
   -- the specific tests that usernames have to pass.
   user_name varchar(255) binary NOT NULL default '',

   -- Optional 'real name' to be displayed in credit listings
   user_real_name varchar(255) binary NOT NULL default '',

   -- Password hashes, see User::crypt() and User::comparePasswords()
   -- in User.php for the algorithm
   user_password tinyblob NOT NULL,

   -- When using 'mail me a new password', a random
   -- password is generated and the hash stored here.
   -- The previous password is left in place until
   -- someone actually logs in with the new password,
   -- at which point the hash is moved to user_password
   -- and the old password is invalidated.
   user_newpassword tinyblob NOT NULL,

   -- Timestamp of the last time when a new password was
   -- sent, for throttling and expiring purposes
   -- Emailed passwords will expire $wgNewPasswordExpiry
   -- (a week) after being set. If user_newpass_time is NULL
   -- (eg. created by mail) it doesn't expire.
   user_newpass_time binary(14),

   -- Note: email should be restricted, not public info.
   -- Same with passwords.
   user_email tinytext NOT NULL,

   -- If the browser sends an If-Modified-Since header, a 304 response is
   -- suppressed if the value in this field for the current user is later than
   -- the value in the IMS header. That is, this field is an invalidation timestamp
   -- for the browser cache of logged-in users. Among other things, it is used
   -- to prevent pages generated for a previously logged in user from being
   -- displayed after a session expiry followed by a fresh login.
   user_touched binary(14) NOT NULL default '',

   -- A pseudorandomly generated value that is stored in
   -- a cookie when the "remember password" feature is
   -- used (previously, a hash of the password was used, but
   -- this was vulnerable to cookie-stealing attacks)
   user_token binary(32) NOT NULL default '',

   -- Initially NULL; when a user's e-mail address has been
   -- validated by returning with a mailed token, this is
   -- set to the current timestamp.
   user_email_authenticated binary(14),

   -- Randomly generated token created when the e-mail address
   -- is set and a confirmation test mail sent.
   user_email_token binary(32),

   -- Expiration date for the user_email_token
   user_email_token_expires binary(14),

   -- Timestamp of account registration.
   -- Accounts predating this schema addition may contain NULL.
   user_registration binary(14),

   -- Count of edits and edit-like actions.
   --
   -- *NOT* intended to be an accurate copy of COUNT(*) WHERE rev_user=user_id
   -- May contain NULL for old accounts if batch-update scripts haven't been
   -- run, as well as listing deleted edits and other myriad ways it could be
   -- out of sync.
   --
   -- Meant primarily for heuristic checks to give an impression of whether
   -- the account has been used much.
   --
   user_editcount int,

   -- Expiration date for user password.
   user_password_expires varbinary(14) DEFAULT NULL

 ) /*$wgDBTableOptions*/;

 CREATE UNIQUE INDEX /*i*/user_name ON /*_*/user (user_name);
 CREATE INDEX /*i*/user_email_token ON /*_*/user (user_email_token);
 CREATE INDEX /*i*/user_email ON /*_*/user (user_email(50));


 --
 -- The "actor" table associates user names or IP addresses with integers for
 -- the benefit of other tables that need to refer to either logged-in or
 -- logged-out users. If something can only ever be done by logged-in users, it
 -- can refer to the user table directly.
 --
 CREATE TABLE /*_*/actor (
   -- Unique ID to identify each actor
   actor_id bigint unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,

   -- Key to user.user_id, or NULL for anonymous edits.
   actor_user int unsigned,

   -- Text username or IP address
   actor_name varchar(255) binary NOT NULL
 ) /*$wgDBTableOptions*/;

 -- User IDs and names must be unique.
 CREATE UNIQUE INDEX /*i*/actor_user ON /*_*/actor (actor_user);
 CREATE UNIQUE INDEX /*i*/actor_name ON /*_*/actor (actor_name);


 --
 -- User permissions have been broken out to a separate table;
 -- this allows sites with a shared user table to have different
 -- permissions assigned to a user in each project.
 --
 -- This table replaces the old user_rights field which used a
 -- comma-separated blob.
 --
 CREATE TABLE /*_*/user_groups (
   -- Key to user_id
   ug_user int unsigned NOT NULL default 0,

   -- Group names are short symbolic string keys.
   -- The set of group names is open-ended, though in practice
   -- only some predefined ones are likely to be used.
   --
   -- At runtime $wgGroupPermissions will associate group keys
   -- with particular permissions. A user will have the combined
   -- permissions of any group they're explicitly in, plus
   -- the implicit '*' and 'user' groups.
   ug_group varbinary(255) NOT NULL default '',

   -- Time at which the user group membership will expire. Set to
   -- NULL for a non-expiring (infinite) membership.
   ug_expiry varbinary(14) NULL default NULL,

   PRIMARY KEY (ug_user, ug_group)
 ) /*$wgDBTableOptions*/;

 CREATE INDEX /*i*/ug_group ON /*_*/user_groups (ug_group);
 CREATE INDEX /*i*/ug_expiry ON /*_*/user_groups (ug_expiry);

 -- Stores the groups the user has once belonged to.
 -- The user may still belong to these groups (check user_groups).
 -- Users are not autopromoted to groups from which they were removed.
 CREATE TABLE /*_*/user_former_groups (
   -- Key to user_id
   ufg_user int unsigned NOT NULL default 0,
   ufg_group varbinary(255) NOT NULL default '',
   PRIMARY KEY (ufg_user,ufg_group)
 ) /*$wgDBTableOptions*/;

 --
 -- Stores notifications of user talk page changes, for the display
 -- of the "you have new messages" box
 --
 CREATE TABLE /*_*/user_newtalk (
   -- Key to user.user_id
   user_id int unsigned NOT NULL default 0,
   -- If the user is an anonymous user their IP address is stored here
   -- since the user_id of 0 is ambiguous
   user_ip varbinary(40) NOT NULL default '',
   -- The highest timestamp of revisions of the talk page viewed
   -- by this user
   user_last_timestamp varbinary(14) NULL default NULL
 ) /*$wgDBTableOptions*/;

 -- Indexes renamed for SQLite in 1.14
 CREATE INDEX /*i*/un_user_id ON /*_*/user_newtalk (user_id);
 CREATE INDEX /*i*/un_user_ip ON /*_*/user_newtalk (user_ip);


 --
 -- User preferences and perhaps other fun stuff. :)
 -- Replaces the old user.user_options blob, with a couple nice properties:
 --
 -- 1) We only store non-default settings, so changes to the defaults
 --    are now reflected for everybody, not just new accounts.
 -- 2) We can more easily do bulk lookups, statistics, or modifications of
 --    saved options since it's a sane table structure.
 --
 CREATE TABLE /*_*/user_properties (
   -- Foreign key to user.user_id
   up_user int unsigned NOT NULL,

   -- Name of the option being saved. This is indexed for bulk lookup.
   up_property varbinary(255) NOT NULL,

   -- Property value as a string.
   up_value blob,
   PRIMARY KEY (up_user,up_property)
 ) /*$wgDBTableOptions*/;

 CREATE INDEX /*i*/user_properties_property ON /*_*/user_properties (up_property);

 --
 -- This table contains a user's bot passwords: passwords that allow access to
 -- the account via the API with limited rights.
 --
 CREATE TABLE /*_*/bot_passwords (
   -- User ID obtained from CentralIdLookup.
   bp_user int unsigned NOT NULL,

   -- Application identifier
   bp_app_id varbinary(32) NOT NULL,

   -- Password hashes, like user.user_password
   bp_password tinyblob NOT NULL,

   -- Like user.user_token
   bp_token binary(32) NOT NULL default '',

   -- JSON blob for MWRestrictions
   bp_restrictions blob NOT NULL,

   -- Grants allowed to the account when authenticated with this bot-password
   bp_grants blob NOT NULL,

   PRIMARY KEY ( bp_user, bp_app_id )
 ) /*$wgDBTableOptions*/;

 --
 -- Core of the wiki: each page has an entry here which identifies
 -- it by title and contains some essential metadata.
 --
 CREATE TABLE /*_*/page (
   -- Unique identifier number. The page_id will be preserved across
   -- edits and rename operations, but not deletions and recreations.
   page_id int unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,

   -- A page name is broken into a namespace and a title.
   -- The namespace keys are UI-language-independent constants,
   -- defined in includes/Defines.php
   page_namespace int NOT NULL,

   -- The rest of the title, as text.
   -- Spaces are transformed into underscores in title storage.
   page_title varchar(255) binary NOT NULL,

   -- Comma-separated set of permission keys indicating who
   -- can move or edit the page.
   page_restrictions tinyblob NOT NULL,

   -- 1 indicates the article is a redirect.
   page_is_redirect tinyint unsigned NOT NULL default 0,

   -- 1 indicates this is a new entry, with only one edit.
   -- Not all pages with one edit are new pages.
   page_is_new tinyint unsigned NOT NULL default 0,

   -- Random value between 0 and 1, used for Special:Randompage
   page_random real unsigned NOT NULL,

   -- This timestamp is updated whenever the page changes in
   -- a way requiring it to be re-rendered, invalidating caches.
   -- Aside from editing this includes permission changes,
   -- creation or deletion of linked pages, and alteration
   -- of contained templates.
   page_touched binary(14) NOT NULL default '',

   -- This timestamp is updated whenever a page is re-parsed and
   -- it has all the link tracking tables updated for it. This is
   -- useful for de-duplicating expensive backlink update jobs.
   page_links_updated varbinary(14) NULL default NULL,

   -- Handy key to revision.rev_id of the current revision.
   -- This may be 0 during page creation, but that shouldn't
   -- happen outside of a transaction... hopefully.
   page_latest int unsigned NOT NULL,

   -- Uncompressed length in bytes of the page's current source text.
   page_len int unsigned NOT NULL,

   -- content model, see CONTENT_MODEL_XXX constants
   page_content_model varbinary(32) DEFAULT NULL,

   -- Page content language
   page_lang varbinary(35) DEFAULT NULL
 ) /*$wgDBTableOptions*/;

 -- The title index. Care must be taken to always specify a namespace when
 -- by title, so that the index is used. Even listing all known namespaces
 -- with IN() is better than omitting page_namespace from the WHERE clause.
 CREATE UNIQUE INDEX /*i*/name_title ON /*_*/page (page_namespace,page_title);

 -- The index for Special:Random
 CREATE INDEX /*i*/page_random ON /*_*/page (page_random);

 -- Questionable utility, used by ProofreadPage, possibly DynamicPageList.
 -- ApiQueryAllPages unconditionally filters on namespace and so hopefully does
 -- not use it.
 CREATE INDEX /*i*/page_len ON /*_*/page (page_len);

 -- The index for Special:Shortpages and Special:Longpages. Also SiteStats::articles()
 -- in 'comma' counting mode, MessageCache::loadFromDB().
 CREATE INDEX /*i*/page_redirect_namespace_len ON /*_*/page (page_is_redirect, page_namespace, page_len);

 --
 -- Every edit of a page creates also a revision row.
 -- This stores metadata about the revision, and a reference
 -- to the text storage backend.
 --
 CREATE TABLE /*_*/revision (
   -- Unique ID to identify each revision
   rev_id int unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,

   -- Key to page_id. This should _never_ be invalid.
   rev_page int unsigned NOT NULL,

   -- Key to text.old_id, where the actual bulk text is stored.
   -- It's possible for multiple revisions to use the same text,
   -- for instance revisions where only metadata is altered
   -- or a rollback to a previous version.
   -- @deprecated since 1.31. If rows in the slots table with slot_revision_id = rev_id
   -- exist, this field should be ignored (and may be 0) in favor of the
   -- corresponding data from the slots and content tables
   rev_text_id int unsigned NOT NULL default 0,

   -- Text comment summarizing the change. Deprecated in favor of
   -- revision_comment_temp.revcomment_comment_id.
   rev_comment varbinary(767) NOT NULL default '',

   -- Key to user.user_id of the user who made this edit.
   -- Stores 0 for anonymous edits and for some mass imports.
   -- Deprecated in favor of revision_actor_temp.revactor_actor.
   rev_user int unsigned NOT NULL default 0,

   -- Text username or IP address of the editor.
   -- Deprecated in favor of revision_actor_temp.revactor_actor.
   rev_user_text varchar(255) binary NOT NULL default '',

   -- Timestamp of when revision was created
   rev_timestamp binary(14) NOT NULL default '',

   -- Records whether the user marked the 'minor edit' checkbox.
   -- Many automated edits are marked as minor.
   rev_minor_edit tinyint unsigned NOT NULL default 0,

   -- Restrictions on who can access this revision
   rev_deleted tinyint unsigned NOT NULL default 0,

   -- Length of this revision in bytes
   rev_len int unsigned,

   -- Key to revision.rev_id
   -- This field is used to add support for a tree structure (The Adjacency List Model)
   rev_parent_id int unsigned default NULL,

   -- SHA-1 text content hash in base-36
   rev_sha1 varbinary(32) NOT NULL default '',

   -- content model, see CONTENT_MODEL_XXX constants
   -- @deprecated since 1.31. If rows in the slots table with slot_revision_id = rev_id
   -- exist, this field should be ignored (and may be NULL) in favor of the
   -- corresponding data from the slots and content tables
   rev_content_model varbinary(32) DEFAULT NULL,

   -- content format, see CONTENT_FORMAT_XXX constants
   -- @deprecated since 1.31. If rows in the slots table with slot_revision_id = rev_id
   -- exist, this field should be ignored (and may be NULL).
   rev_content_format varbinary(64) DEFAULT NULL

 ) /*$wgDBTableOptions*/ MAX_ROWS=10000000 AVG_ROW_LENGTH=1024;
 -- In case tables are created as MyISAM, use row hints for MySQL <5.0 to avoid 4GB limit

 -- The index is proposed for removal, do not use it in new code: T163532.
 -- Used for ordering revisions within a page by rev_id, which is usually
 -- incorrect, since rev_timestamp is normally the correct order. It can also
 -- be used by dumpBackup.php, if a page and rev_id range is specified.
 CREATE INDEX /*i*/rev_page_id ON /*_*/revision (rev_page, rev_id);

 -- Used by ApiQueryAllRevisions
 CREATE INDEX /*i*/rev_timestamp ON /*_*/revision (rev_timestamp);

 -- History index
 CREATE INDEX /*i*/page_timestamp ON /*_*/revision (rev_page,rev_timestamp);

 -- Logged-in user contributions index
 CREATE INDEX /*i*/user_timestamp ON /*_*/revision (rev_user,rev_timestamp);

 -- Anonymous user countributions index
 CREATE INDEX /*i*/usertext_timestamp ON /*_*/revision (rev_user_text,rev_timestamp);

 -- Credits index. This is scanned in order to compile credits lists for pages,
 -- in ApiQueryContributors. Also for ApiQueryRevisions if rvuser is specified
 -- and is a logged-in user.
 CREATE INDEX /*i*/page_user_timestamp ON /*_*/revision (rev_page,rev_user,rev_timestamp);

 --
 -- Temporary table to avoid blocking on an alter of revision.
 --
 -- On large wikis like the English Wikipedia, altering the revision table is a
 -- months-long process. This table is being created to avoid such an alter, and
 -- will be merged back into revision in the future.
 --
 CREATE TABLE /*_*/revision_comment_temp (
   -- Key to rev_id
   revcomment_rev int unsigned NOT NULL,
   -- Key to comment_id
   revcomment_comment_id bigint unsigned NOT NULL,
   PRIMARY KEY (revcomment_rev, revcomment_comment_id)
 ) /*$wgDBTableOptions*/;
 -- Ensure uniqueness
 CREATE UNIQUE INDEX /*i*/revcomment_rev ON /*_*/revision_comment_temp (revcomment_rev);

 --
 -- Temporary table to avoid blocking on an alter of revision.
 --
 -- On large wikis like the English Wikipedia, altering the revision table is a
 -- months-long process. This table is being created to avoid such an alter, and
 -- will be merged back into revision in the future.
 --
 CREATE TABLE /*_*/revision_actor_temp (
   -- Key to rev_id
   revactor_rev int unsigned NOT NULL,
   -- Key to actor_id
   revactor_actor bigint unsigned NOT NULL,
   -- Copy fields from revision for indexes
   revactor_timestamp binary(14) NOT NULL default '',
   revactor_page int unsigned NOT NULL,
   PRIMARY KEY (revactor_rev, revactor_actor)
 ) /*$wgDBTableOptions*/;
 -- Ensure uniqueness
 CREATE UNIQUE INDEX /*i*/revactor_rev ON /*_*/revision_actor_temp (revactor_rev);
 -- Match future indexes on revision
 CREATE INDEX /*i*/actor_timestamp ON /*_*/revision_actor_temp (revactor_actor,revactor_timestamp);
 CREATE INDEX /*i*/page_actor_timestamp ON /*_*/revision_actor_temp (revactor_page,revactor_actor,revactor_timestamp);

 --
 -- Every time an edit by a logged out user is saved,
 -- a row is created in ip_changes. This stores
 -- the IP as a hex representation so that we can more
 -- easily find edits within an IP range.
 --
 CREATE TABLE /*_*/ip_changes (
   -- Foreign key to the revision table, also serves as the unique primary key
   ipc_rev_id int unsigned NOT NULL PRIMARY KEY DEFAULT '0',

   -- The timestamp of the revision
   ipc_rev_timestamp binary(14) NOT NULL DEFAULT '',

   -- Hex representation of the IP address, as returned by IP::toHex()
   -- For IPv4 it will resemble: ABCD1234
   -- For IPv6: v6-ABCD1234000000000000000000000000
   -- BETWEEN is then used to identify revisions within a given range
   ipc_hex varbinary(35) NOT NULL DEFAULT ''

 ) /*$wgDBTableOptions*/;

 CREATE INDEX /*i*/ipc_rev_timestamp ON /*_*/ip_changes (ipc_rev_timestamp);
 CREATE INDEX /*i*/ipc_hex_time ON /*_*/ip_changes (ipc_hex,ipc_rev_timestamp);

 --
 -- Holds text of individual page revisions.
 --
 -- Field names are a holdover from the 'old' revisions table in
 -- MediaWiki 1.4 and earlier: an upgrade will transform that
 -- table into the 'text' table to minimize unnecessary churning
 -- and downtime. If upgrading, the other fields will be left unused.
 --
 CREATE TABLE /*_*/text (
   -- Unique text storage key number.
   -- Note that the 'oldid' parameter used in URLs does *not*
   -- refer to this number anymore, but to rev_id.
   --
   -- revision.rev_text_id is a key to this column
   old_id int unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,

   -- Depending on the contents of the old_flags field, the text
   -- may be convenient plain text, or it may be funkily encoded.
   old_text mediumblob NOT NULL,

   -- Comma-separated list of flags:
   -- gzip: text is compressed with PHP's gzdeflate() function.
   -- utf-8: text was stored as UTF-8.
   --        If $wgLegacyEncoding option is on, rows *without* this flag
   --        will be converted to UTF-8 transparently at load time. Note
   --        that due to a bug in a maintenance script, this flag may
   --        have been stored as 'utf8' in some cases (T18841).
   -- object: text field contained a serialized PHP object.
   --         The object either contains multiple versions compressed
   --         together to achieve a better compression ratio, or it refers
   --         to another row where the text can be found.
   -- external: text was stored in an external location specified by old_text.
   --           Any additional flags apply to the data stored at that URL, not
   --           the URL itself. The 'object' flag is *not* set for URLs of the
   --           form 'DB://cluster/id/itemid', because the external storage
   --           system itself decompresses these.
   old_flags tinyblob NOT NULL
 ) /*$wgDBTableOptions*/ MAX_ROWS=10000000 AVG_ROW_LENGTH=10240;
 -- In case tables are created as MyISAM, use row hints for MySQL <5.0 to avoid 4GB limit


 --
 -- Edits, blocks, and other actions typically have a textual comment describing
 -- the action. They are stored here to reduce the size of the main tables, and
 -- to allow for deduplication.
 --
 -- Deduplication is currently best-effort to avoid locking on inserts that
 -- would be required for strict deduplication. There MAY be multiple rows with
 -- the same comment_text and comment_data.
 --
 CREATE TABLE /*_*/comment (
   -- Unique ID to identify each comment
   comment_id bigint unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,

   -- Hash of comment_text and comment_data, for deduplication
   comment_hash INT NOT NULL,

   -- Text comment summarizing the change.
   -- This text is shown in the history and other changes lists,
   -- rendered in a subset of wiki markup by Linker::formatComment()
   -- Size limits are enforced at the application level, and should
   -- take care to crop UTF-8 strings appropriately.
   comment_text BLOB NOT NULL,

   -- JSON data, intended for localizing auto-generated comments.
   -- This holds structured data that is intended to be used to provide
   -- localized versions of automatically-generated comments. When not empty,
   -- comment_text should be the generated comment localized using the wiki's
   -- content language.
   comment_data BLOB
 ) /*$wgDBTableOptions*/;
 -- Index used for deduplication.
 CREATE INDEX /*i*/comment_hash ON /*_*/comment (comment_hash);


 --
 -- Archive area for deleted pages and their revisions.
 -- These may be viewed (and restored) by admins through the Special:Undelete interface.
 --
 CREATE TABLE /*_*/archive (
   -- Primary key
   ar_id int unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,

   -- Copied from page_namespace
   ar_namespace int NOT NULL default 0,
   -- Copied from page_title
   ar_title varchar(255) binary NOT NULL default '',

   -- Basic revision stuff...
   ar_comment_id bigint unsigned NOT NULL,
   ar_actor bigint unsigned NOT NULL,
   ar_timestamp binary(14) NOT NULL default '',
   ar_minor_edit tinyint NOT NULL default 0,

   -- Copied from rev_id.
   --
   -- @since 1.5 Entries from 1.4 will be NULL here. When restoring
   -- archive rows from before 1.5, a new rev_id is created.
   ar_rev_id int unsigned NOT NULL,

   -- Copied from rev_text_id, references text.old_id.
   -- To avoid breaking the block-compression scheme and otherwise making
   -- storage changes harder, the actual text is *not* deleted from the
   -- text storage. Instead, it is merely hidden from public view, by removal
   -- of the page and revision entries.
   --
   -- @deprecated since 1.31. If rows in the slots table with slot_revision_id = ar_rev_id
   -- exist, this field should be ignored (and may be 0) in favor of the
   -- corresponding data from the slots and content tables
   ar_text_id int unsigned NOT NULL DEFAULT 0,

   -- Copied from rev_deleted. Although this may be raised during deletion.
   -- Users with the "suppressrevision" right may "archive" and "suppress"
   -- content in a single action.
   -- @since 1.10
   ar_deleted tinyint unsigned NOT NULL default 0,

   -- Copied from rev_len, length of this revision in bytes.
   -- @since 1.10
   ar_len int unsigned,

   -- Copied from page_id. Restoration will attempt to use this as page ID if
   -- no current page with the same name exists. Otherwise, the revisions will
   -- be restored under the current page. Can be used for manual undeletion by
   -- developers if multiple pages by the same name were archived.
   --
   -- @since 1.11 Older entries will have NULL.
   ar_page_id int unsigned,

   -- Copied from rev_parent_id.
   -- @since 1.13
   ar_parent_id int unsigned default NULL,

   -- Copied from rev_sha1, SHA-1 text content hash in base-36
   -- @since 1.19
   ar_sha1 varbinary(32) NOT NULL default '',

   -- Copied from rev_content_model, see CONTENT_MODEL_XXX constants
   -- @since 1.21
   -- @deprecated since 1.31. If rows in the slots table with slot_revision_id = ar_rev_id
   -- exist, this field should be ignored (and may be NULL) in favor of the
   -- corresponding data from the slots and content tables
   ar_content_model varbinary(32) DEFAULT NULL,

   -- Copied from rev_content_format, see CONTENT_FORMAT_XXX constants
   -- @since 1.21
   -- @deprecated since 1.31. If rows in the slots table with slot_revision_id = ar_rev_id
   -- exist, this field should be ignored (and may be NULL).
   ar_content_format varbinary(64) DEFAULT NULL
 ) /*$wgDBTableOptions*/;

 -- Index for Special:Undelete to page through deleted revisions
 CREATE INDEX /*i*/name_title_timestamp ON /*_*/archive (ar_namespace,ar_title,ar_timestamp);

 -- Index for Special:DeletedContributions
 CREATE INDEX /*i*/ar_actor_timestamp ON /*_*/archive (ar_actor,ar_timestamp);

 -- Index for linking archive rows with tables that normally link with revision
 -- rows, such as change_tag.
 CREATE UNIQUE INDEX /*i*/ar_revid_uniq ON /*_*/archive (ar_rev_id);

 --
 -- Slots represent an n:m relation between revisions and content objects.
 -- A content object can have a specific "role" in one or more revisions.
 -- Each revision can have multiple content objects, each having a different role.
 --
 CREATE TABLE /*_*/slots (

   -- reference to rev_id or ar_rev_id
   slot_revision_id bigint unsigned NOT NULL,

   -- reference to role_id
   slot_role_id smallint unsigned NOT NULL,

   -- reference to content_id
   slot_content_id bigint unsigned NOT NULL,

   -- The revision ID of the revision that originated the slot's content.
   -- To find revisions that changed slots, look for slot_origin = slot_revision_id.
   -- TODO: Is that actually true? Rollback seems to violate it by setting
   --  slot_origin to an older rev_id. Undeletions could result in the same situation.
   slot_origin bigint unsigned NOT NULL,

   PRIMARY KEY ( slot_revision_id, slot_role_id )
 ) /*$wgDBTableOptions*/;

 -- Index for finding revisions that modified a specific slot
 CREATE INDEX /*i*/slot_revision_origin_role ON /*_*/slots (slot_revision_id, slot_origin, slot_role_id);

 --
 -- The content table represents content objects. It's primary purpose is to provide the necessary
 -- meta-data for loading and interpreting a serialized data blob to create a content object.
 --
 CREATE TABLE /*_*/content (

   -- ID of the content object
   content_id bigint unsigned PRIMARY KEY AUTO_INCREMENT,

   -- Nominal size of the content object (not necessarily of the serialized blob)
   content_size int unsigned NOT NULL,

   -- Nominal hash of the content object (not necessarily of the serialized blob)
   content_sha1 varbinary(32) NOT NULL,

   -- reference to model_id. Note the content format isn't specified; it should
   -- be assumed to be in the default format for the model unless auto-detected
   -- otherwise.
   content_model smallint unsigned NOT NULL,

   -- URL-like address of the content blob
   content_address varbinary(255) NOT NULL
 ) /*$wgDBTableOptions*/;

 --
 -- Normalization table for role names
 --
 CREATE TABLE /*_*/slot_roles (
   role_id smallint PRIMARY KEY AUTO_INCREMENT,
   role_name varbinary(64) NOT NULL
 ) /*$wgDBTableOptions*/;

 -- Index for looking of the internal ID of for a name
 CREATE UNIQUE INDEX /*i*/role_name ON /*_*/slot_roles (role_name);

 --
 -- Normalization table for content model names
 --
 CREATE TABLE /*_*/content_models (
   model_id smallint PRIMARY KEY AUTO_INCREMENT,
   model_name varbinary(64) NOT NULL
 ) /*$wgDBTableOptions*/;

 -- Index for looking of the internal ID of for a name
 CREATE UNIQUE INDEX /*i*/model_name ON /*_*/content_models (model_name);

 --
 -- Track page-to-page hyperlinks within the wiki.
 --
 CREATE TABLE /*_*/pagelinks (
   -- Key to the page_id of the page containing the link.
   pl_from int unsigned NOT NULL default 0,
   -- Namespace for this page
   pl_from_namespace int NOT NULL default 0,

   -- Key to page_namespace/page_title of the target page.
   -- The target page may or may not exist, and due to renames
   -- and deletions may refer to different page records as time
   -- goes by.
   pl_namespace int NOT NULL default 0,
   pl_title varchar(255) binary NOT NULL default '',
   PRIMARY KEY (pl_from,pl_namespace,pl_title)
 ) /*$wgDBTableOptions*/;

 -- Reverse index, for Special:Whatlinkshere
 CREATE INDEX /*i*/pl_namespace ON /*_*/pagelinks (pl_namespace,pl_title,pl_from);

 -- Index for Special:Whatlinkshere with namespace filter
 CREATE INDEX /*i*/pl_backlinks_namespace ON /*_*/pagelinks (pl_from_namespace,pl_namespace,pl_title,pl_from);


 --
 -- Track template inclusions.
 --
 CREATE TABLE /*_*/templatelinks (
   -- Key to the page_id of the page containing the link.
   tl_from int unsigned NOT NULL default 0,
   -- Namespace for this page
   tl_from_namespace int NOT NULL default 0,

   -- Key to page_namespace/page_title of the target page.
   -- The target page may or may not exist, and due to renames
   -- and deletions may refer to different page records as time
   -- goes by.
   tl_namespace int NOT NULL default 0,
   tl_title varchar(255) binary NOT NULL default '',
   PRIMARY KEY (tl_from,tl_namespace,tl_title)
 ) /*$wgDBTableOptions*/;

 -- Reverse index, for Special:Whatlinkshere
 CREATE INDEX /*i*/tl_namespace ON /*_*/templatelinks (tl_namespace,tl_title,tl_from);

 -- Index for Special:Whatlinkshere with namespace filter
 CREATE INDEX /*i*/tl_backlinks_namespace ON /*_*/templatelinks (tl_from_namespace,tl_namespace,tl_title,tl_from);


 --
 -- Track links to images *used inline*
 -- We don't distinguish live from broken links here, so
 -- they do not need to be changed on upload/removal.
 --
 CREATE TABLE /*_*/imagelinks (
   -- Key to page_id of the page containing the image / media link.
   il_from int unsigned NOT NULL default 0,
   -- Namespace for this page
   il_from_namespace int NOT NULL default 0,

   -- Filename of target image.
   -- This is also the page_title of the file's description page;
   -- all such pages are in namespace 6 (NS_FILE).
   il_to varchar(255) binary NOT NULL default '',
   PRIMARY KEY (il_from,il_to)
 ) /*$wgDBTableOptions*/;

 -- Reverse index, for Special:Whatlinkshere and file description page local usage
 CREATE INDEX /*i*/il_to ON /*_*/imagelinks (il_to,il_from);

 -- Index for Special:Whatlinkshere with namespace filter
 CREATE INDEX /*i*/il_backlinks_namespace ON /*_*/imagelinks (il_from_namespace,il_to,il_from);


 --
 -- Track category inclusions *used inline*
 -- This tracks a single level of category membership
 --
 CREATE TABLE /*_*/categorylinks (
   -- Key to page_id of the page defined as a category member.
   cl_from int unsigned NOT NULL default 0,

   -- Name of the category.
   -- This is also the page_title of the category's description page;
   -- all such pages are in namespace 14 (NS_CATEGORY).
   cl_to varchar(255) binary NOT NULL default '',

   -- A binary string obtained by applying a sortkey generation algorithm
   -- (Collation::getSortKey()) to page_title, or cl_sortkey_prefix . "\n"
   -- . page_title if cl_sortkey_prefix is nonempty.
   cl_sortkey varbinary(230) NOT NULL default '',

   -- A prefix for the raw sortkey manually specified by the user, either via
   -- [[Category:Foo|prefix]] or {{defaultsort:prefix}}.  If nonempty, it's
   -- concatenated with a line break followed by the page title before the sortkey
   -- conversion algorithm is run.  We store this so that we can update
   -- collations without reparsing all pages.
   -- Note: If you change the length of this field, you also need to change
   -- code in LinksUpdate.php. See T27254.
   cl_sortkey_prefix varchar(255) binary NOT NULL default '',

   -- This isn't really used at present. Provided for an optional
   -- sorting method by approximate addition time.
   cl_timestamp timestamp NOT NULL,

   -- Stores $wgCategoryCollation at the time cl_sortkey was generated.  This
   -- can be used to install new collation versions, tracking which rows are not
   -- yet updated.  '' means no collation, this is a legacy row that needs to be
   -- updated by updateCollation.php.  In the future, it might be possible to
   -- specify different collations per category.
   cl_collation varbinary(32) NOT NULL default '',

   -- Stores whether cl_from is a category, file, or other page, so we can
   -- paginate the three categories separately.  This never has to be updated
   -- after the page is created, since none of these page types can be moved to
   -- any other.
   cl_type ENUM('page', 'subcat', 'file') NOT NULL default 'page',
   PRIMARY KEY (cl_from,cl_to)
 ) /*$wgDBTableOptions*/;


 -- We always sort within a given category, and within a given type.  FIXME:
 -- Formerly this index didn't cover cl_type (since that didn't exist), so old
 -- callers won't be using an index: fix this?
 CREATE INDEX /*i*/cl_sortkey ON /*_*/categorylinks (cl_to,cl_type,cl_sortkey,cl_from);

 -- Used by the API (and some extensions)
 CREATE INDEX /*i*/cl_timestamp ON /*_*/categorylinks (cl_to,cl_timestamp);

 -- Used when updating collation (e.g. updateCollation.php)
 CREATE INDEX /*i*/cl_collation_ext ON /*_*/categorylinks (cl_collation, cl_to, cl_type, cl_from);

 --
 -- Track all existing categories. Something is a category if 1) it has an entry
 -- somewhere in categorylinks, or 2) it has a description page. Categories
 -- might not have corresponding pages, so they need to be tracked separately.
 --
 CREATE TABLE /*_*/category (
   -- Primary key
   cat_id int unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,

   -- Name of the category, in the same form as page_title (with underscores).
   -- If there is a category page corresponding to this category, by definition,
   -- it has this name (in the Category namespace).
   cat_title varchar(255) binary NOT NULL,

   -- The numbers of member pages (including categories and media), subcatego-
   -- ries, and Image: namespace members, respectively.  These are signed to
   -- make underflow more obvious.  We make the first number include the second
   -- two for better sorting: subtracting for display is easy, adding for order-
   -- ing is not.
   cat_pages int signed NOT NULL default 0,
   cat_subcats int signed NOT NULL default 0,
   cat_files int signed NOT NULL default 0
 ) /*$wgDBTableOptions*/;

 CREATE UNIQUE INDEX /*i*/cat_title ON /*_*/category (cat_title);

 -- For Special:Mostlinkedcategories
 CREATE INDEX /*i*/cat_pages ON /*_*/category (cat_pages);


 --
 -- Track links to external URLs
 --
 CREATE TABLE /*_*/externallinks (
   -- Primary key
   el_id int unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,

   -- page_id of the referring page
   el_from int unsigned NOT NULL default 0,

   -- The URL
   el_to blob NOT NULL,

   -- In the case of HTTP URLs, this is the URL with any username or password
   -- removed, and with the labels in the hostname reversed and converted to
   -- lower case. An extra dot is added to allow for matching of either
   -- example.com or *.example.com in a single scan.
   -- Example:
   --      http://user:password@sub.example.com/page.html
   --   becomes
   --      http://com.example.sub./page.html
   -- which allows for fast searching for all pages under example.com with the
   -- clause:
   --      WHERE el_index LIKE 'http://com.example.%'
   --
   -- Note if you enable or disable PHP's intl extension, you'll need to run
   -- maintenance/refreshExternallinksIndex.php to refresh this field.
   el_index blob NOT NULL,

   -- This is el_index truncated to 60 bytes to allow for sortable queries that
   -- aren't supported by a partial index.
   el_index_60 varbinary(60) NOT NULL
 ) /*$wgDBTableOptions*/;

 -- Forward index, for page edit, save
 CREATE INDEX /*i*/el_from ON /*_*/externallinks (el_from, el_to(40));

 -- Index for Special:LinkSearch exact search
 CREATE INDEX /*i*/el_to ON /*_*/externallinks (el_to(60), el_from);

 -- For Special:LinkSearch wildcard search
 CREATE INDEX /*i*/el_index ON /*_*/externallinks (el_index(60));

 -- For Special:LinkSearch wildcard search with efficient paging by el_id
 CREATE INDEX /*i*/el_index_60 ON /*_*/externallinks (el_index_60, el_id);
 CREATE INDEX /*i*/el_from_index_60 ON /*_*/externallinks (el_from, el_index_60, el_id);

 --
 -- Track interlanguage links
 --
 CREATE TABLE /*_*/langlinks (
   -- page_id of the referring page
   ll_from int unsigned NOT NULL default 0,

   -- Language code of the target
   ll_lang varbinary(20) NOT NULL default '',

   -- Title of the target, including namespace
   ll_title varchar(255) binary NOT NULL default '',
   PRIMARY KEY (ll_from,ll_lang)
 ) /*$wgDBTableOptions*/;

 -- Index for ApiQueryLangbacklinks
 CREATE INDEX /*i*/ll_lang ON /*_*/langlinks (ll_lang, ll_title);


 --
 -- Track inline interwiki links
 --
 CREATE TABLE /*_*/iwlinks (
   -- page_id of the referring page
   iwl_from int unsigned NOT NULL default 0,

   -- Interwiki prefix code of the target
   iwl_prefix varbinary(20) NOT NULL default '',

   -- Title of the target, including namespace
   iwl_title varchar(255) binary NOT NULL default '',
   PRIMARY KEY (iwl_from,iwl_prefix,iwl_title)
 ) /*$wgDBTableOptions*/;

 -- Index for ApiQueryIWBacklinks
 CREATE INDEX /*i*/iwl_prefix_title_from ON /*_*/iwlinks (iwl_prefix, iwl_title, iwl_from);

 -- Index for ApiQueryIWLinks
 CREATE INDEX /*i*/iwl_prefix_from_title ON /*_*/iwlinks (iwl_prefix, iwl_from, iwl_title);


 --
 -- Contains a single row with some aggregate info
 -- on the state of the site.
 --
 CREATE TABLE /*_*/site_stats (
   -- The single row should contain 1 here.
   ss_row_id int unsigned NOT NULL PRIMARY KEY,

   -- Total number of edits performed.
   ss_total_edits bigint unsigned default NULL,

   -- See SiteStatsInit::articles().
   ss_good_articles bigint unsigned default NULL,

   -- Total pages, theoretically equal to SELECT COUNT(*) FROM page.
   ss_total_pages bigint unsigned default NULL,

   -- Number of users, theoretically equal to SELECT COUNT(*) FROM user.
   ss_users bigint unsigned default NULL,

   -- Number of users that still edit.
   ss_active_users bigint unsigned default NULL,

   -- Number of images, equivalent to SELECT COUNT(*) FROM image.
   ss_images bigint unsigned default NULL
 ) /*$wgDBTableOptions*/;

 --
 -- The internet is full of jerks, alas. Sometimes it's handy
 -- to block a vandal or troll account.
 --
 CREATE TABLE /*_*/ipblocks (
   -- Primary key, introduced for privacy.
   ipb_id int NOT NULL PRIMARY KEY AUTO_INCREMENT,

   -- Blocked IP address in dotted-quad form or user name.
   ipb_address tinyblob NOT NULL,

   -- Blocked user ID or 0 for IP blocks.
   ipb_user int unsigned NOT NULL default 0,

   -- Actor who made the block.
   ipb_by_actor bigint unsigned NOT NULL,

   -- Key to comment_id. Text comment made by blocker.
   ipb_reason_id bigint unsigned NOT NULL,

   -- Creation (or refresh) date in standard YMDHMS form.
   -- IP blocks expire automatically.
   ipb_timestamp binary(14) NOT NULL default '',

   -- Indicates that the IP address was banned because a banned
   -- user accessed a page through it. If this is 1, ipb_address
   -- will be hidden, and the block identified by block ID number.
   ipb_auto bool NOT NULL default 0,

   -- If set to 1, block applies only to logged-out users
   ipb_anon_only bool NOT NULL default 0,

   -- Block prevents account creation from matching IP addresses
   ipb_create_account bool NOT NULL default 1,

   -- Block triggers autoblocks
   ipb_enable_autoblock bool NOT NULL default '1',

   -- Time at which the block will expire.
   -- May be "infinity"
   ipb_expiry varbinary(14) NOT NULL default '',

   -- Start and end of an address range, in hexadecimal
   -- Size chosen to allow IPv6
   -- FIXME: these fields were originally blank for single-IP blocks,
   -- but now they are populated. No migration was ever done. They
   -- should be fixed to be blank again for such blocks (T51504).
   ipb_range_start tinyblob NOT NULL,
   ipb_range_end tinyblob NOT NULL,

   -- Flag for entries hidden from users and Sysops
   ipb_deleted bool NOT NULL default 0,

   -- Block prevents user from accessing Special:Emailuser
   ipb_block_email bool NOT NULL default 0,

   -- Block allows user to edit their own talk page
   ipb_allow_usertalk bool NOT NULL default 0,

   -- ID of the block that caused this block to exist
   -- Autoblocks set this to the original block
   -- so that the original block being deleted also
   -- deletes the autoblocks
   ipb_parent_block_id int default NULL,

   -- Block user from editing any page on the site (other than their own user
   -- talk page).
   ipb_sitewide bool NOT NULL default 1

 ) /*$wgDBTableOptions*/;

 -- Unique index to support "user already blocked" messages
 -- Any new options which prevent collisions should be included
 CREATE UNIQUE INDEX /*i*/ipb_address ON /*_*/ipblocks (ipb_address(255), ipb_user, ipb_auto, ipb_anon_only);

 -- For querying whether a logged-in user is blocked
 CREATE INDEX /*i*/ipb_user ON /*_*/ipblocks (ipb_user);

 -- For querying whether an IP address is in any range
 CREATE INDEX /*i*/ipb_range ON /*_*/ipblocks (ipb_range_start(8), ipb_range_end(8));

 -- Index for Special:BlockList
 CREATE INDEX /*i*/ipb_timestamp ON /*_*/ipblocks (ipb_timestamp);

 -- Index for table pruning
 CREATE INDEX /*i*/ipb_expiry ON /*_*/ipblocks (ipb_expiry);

 -- Index for removing autoblocks when a parent block is removed
 CREATE INDEX /*i*/ipb_parent_block_id ON /*_*/ipblocks (ipb_parent_block_id);

 --
 -- Partial Block Restrictions
 --
 CREATE TABLE /*_*/ipblocks_restrictions (

   -- The ipb_id from ipblocks
   ir_ipb_id int NOT NULL,

   -- The restriction type id.
   ir_type tinyint(1) NOT NULL,

   -- The restriction id that corrposponds to the type. Typically a Page ID or a
   -- Namespace ID.
   ir_value int NOT NULL,

   PRIMARY KEY (ir_ipb_id, ir_type, ir_value)
 ) /*$wgDBTableOptions*/;

 -- Index to query restrictions by the page or namespace.
 CREATE INDEX /*i*/ir_type_value ON /*_*/ipblocks_restrictions (ir_type, ir_value);

 --
 -- Uploaded images and other files.
 --
 CREATE TABLE /*_*/image (
   -- Filename.
   -- This is also the title of the associated description page,
   -- which will be in namespace 6 (NS_FILE).
   img_name varchar(255) binary NOT NULL default '' PRIMARY KEY,

   -- File size in bytes.
   img_size int unsigned NOT NULL default 0,

   -- For images, size in pixels.
   img_width int NOT NULL default 0,
   img_height int NOT NULL default 0,

   -- Extracted Exif metadata stored as a serialized PHP array.
   img_metadata mediumblob NOT NULL,

   -- For images, bits per pixel if known.
   img_bits int NOT NULL default 0,

   -- Media type as defined by the MEDIATYPE_xxx constants
   img_media_type ENUM("UNKNOWN", "BITMAP", "DRAWING", "AUDIO", "VIDEO", "MULTIMEDIA", "OFFICE", "TEXT", "EXECUTABLE", "ARCHIVE", "3D") default NULL,

   -- major part of a MIME media type as defined by IANA
   -- see https://www.iana.org/assignments/media-types/
   -- for "chemical" cf. http://dx.doi.org/10.1021/ci9803233 by the ACS
   img_major_mime ENUM("unknown", "application", "audio", "image", "text", "video", "message", "model", "multipart", "chemical") NOT NULL default "unknown",

   -- minor part of a MIME media type as defined by IANA
   -- the minor parts are not required to adher to any standard
   -- but should be consistent throughout the database
   -- see https://www.iana.org/assignments/media-types/
   img_minor_mime varbinary(100) NOT NULL default "unknown",

   -- Foreign key to comment table, which contains the description field as entered by the uploader.
   -- This is displayed in image upload history and logs.
   img_description_id bigint unsigned NOT NULL,

   -- actor_id of the uploader.
   img_actor bigint unsigned NOT NULL,

   -- Time of the upload.
   img_timestamp varbinary(14) NOT NULL default '',

   -- SHA-1 content hash in base-36
   img_sha1 varbinary(32) NOT NULL default ''
 ) /*$wgDBTableOptions*/;

 -- Used by Special:Newimages and ApiQueryAllImages
 CREATE INDEX /*i*/img_actor_timestamp ON /*_*/image (img_actor,img_timestamp);
 -- Used by Special:ListFiles for sort-by-size
 CREATE INDEX /*i*/img_size ON /*_*/image (img_size);
 -- Used by Special:Newimages and Special:ListFiles
 CREATE INDEX /*i*/img_timestamp ON /*_*/image (img_timestamp);
 -- Used in API and duplicate search
 CREATE INDEX /*i*/img_sha1 ON /*_*/image (img_sha1(10));
 -- Used to get media of one type
 CREATE INDEX /*i*/img_media_mime ON /*_*/image (img_media_type,img_major_mime,img_minor_mime);


 --
 -- Previous revisions of uploaded files.
 -- Awkwardly, image rows have to be moved into
 -- this table at re-upload time.
 --
 CREATE TABLE /*_*/oldimage (
   -- Base filename: key to image.img_name
   oi_name varchar(255) binary NOT NULL default '',

   -- Filename of the archived file.
   -- This is generally a timestamp and '!' prepended to the base name.
   oi_archive_name varchar(255) binary NOT NULL default '',

   -- Other fields as in image...
   oi_size int unsigned NOT NULL default 0,
   oi_width int NOT NULL default 0,
   oi_height int NOT NULL default 0,
   oi_bits int NOT NULL default 0,
   oi_description_id bigint unsigned NOT NULL,
   oi_actor bigint unsigned NOT NULL,
   oi_timestamp binary(14) NOT NULL default '',

   oi_metadata mediumblob NOT NULL,
   oi_media_type ENUM("UNKNOWN", "BITMAP", "DRAWING", "AUDIO", "VIDEO", "MULTIMEDIA", "OFFICE", "TEXT", "EXECUTABLE", "ARCHIVE", "3D") default NULL,
   oi_major_mime ENUM("unknown", "application", "audio", "image", "text", "video", "message", "model", "multipart", "chemical") NOT NULL default "unknown",
   oi_minor_mime varbinary(100) NOT NULL default "unknown",
   oi_deleted tinyint unsigned NOT NULL default 0,
   oi_sha1 varbinary(32) NOT NULL default ''
 ) /*$wgDBTableOptions*/;

 CREATE INDEX /*i*/oi_actor_timestamp ON /*_*/oldimage (oi_actor,oi_timestamp);
 CREATE INDEX /*i*/oi_name_timestamp ON /*_*/oldimage (oi_name,oi_timestamp);
 -- oi_archive_name truncated to 14 to avoid key length overflow
 CREATE INDEX /*i*/oi_name_archive_name ON /*_*/oldimage (oi_name,oi_archive_name(14));
 CREATE INDEX /*i*/oi_sha1 ON /*_*/oldimage (oi_sha1(10));


 --
 -- Record of deleted file data
 --
 CREATE TABLE /*_*/filearchive (
   -- Unique row id
   fa_id int NOT NULL PRIMARY KEY AUTO_INCREMENT,

   -- Original base filename; key to image.img_name, page.page_title, etc
   fa_name varchar(255) binary NOT NULL default '',

   -- Filename of archived file, if an old revision
   fa_archive_name varchar(255) binary default '',

   -- Which storage bin (directory tree or object store) the file data
   -- is stored in. Should be 'deleted' for files that have been deleted;
   -- any other bin is not yet in use.
   fa_storage_group varbinary(16),

   -- SHA-1 of the file contents plus extension, used as a key for storage.
   -- eg 8f8a562add37052a1848ff7771a2c515db94baa9.jpg
   --
   -- If NULL, the file was missing at deletion time or has been purged
   -- from the archival storage.
   fa_storage_key varbinary(64) default '',

   -- Deletion information, if this file is deleted.
   fa_deleted_user int,
   fa_deleted_timestamp binary(14) default '',
   fa_deleted_reason_id bigint unsigned NOT NULL,

   -- Duped fields from image
   fa_size int unsigned default 0,
   fa_width int default 0,
   fa_height int default 0,
   fa_metadata mediumblob,
   fa_bits int default 0,
   fa_media_type ENUM("UNKNOWN", "BITMAP", "DRAWING", "AUDIO", "VIDEO", "MULTIMEDIA", "OFFICE", "TEXT", "EXECUTABLE", "ARCHIVE", "3D") default NULL,
   fa_major_mime ENUM("unknown", "application", "audio", "image", "text", "video", "message", "model", "multipart", "chemical") default "unknown",
   fa_minor_mime varbinary(100) default "unknown",
   fa_description_id bigint unsigned NOT NULL,
   fa_actor bigint unsigned NOT NULL,
   fa_timestamp binary(14) default '',

   -- Visibility of deleted revisions, bitfield
   fa_deleted tinyint unsigned NOT NULL default 0,

   -- sha1 hash of file content
   fa_sha1 varbinary(32) NOT NULL default ''
 ) /*$wgDBTableOptions*/;

 -- pick out by image name
 CREATE INDEX /*i*/fa_name ON /*_*/filearchive (fa_name, fa_timestamp);
 -- pick out dupe files
 CREATE INDEX /*i*/fa_storage_group ON /*_*/filearchive (fa_storage_group, fa_storage_key);
 -- sort by deletion time
 CREATE INDEX /*i*/fa_deleted_timestamp ON /*_*/filearchive (fa_deleted_timestamp);
 -- sort by uploader
 CREATE INDEX /*i*/fa_actor_timestamp ON /*_*/filearchive (fa_actor,fa_timestamp);
 -- find file by sha1, 10 bytes will be enough for hashes to be indexed
 CREATE INDEX /*i*/fa_sha1 ON /*_*/filearchive (fa_sha1(10));


 --
 -- Store information about newly uploaded files before they're
 -- moved into the actual filestore
 --
 CREATE TABLE /*_*/uploadstash (
   us_id int unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,

   -- the user who uploaded the file.
   us_user int unsigned NOT NULL,

   -- file key. this is how applications actually search for the file.
   -- this might go away, or become the primary key.
   us_key varchar(255) NOT NULL,

   -- the original path
   us_orig_path varchar(255) NOT NULL,

   -- the temporary path at which the file is actually stored
   us_path varchar(255) NOT NULL,

   -- which type of upload the file came from (sometimes)
   us_source_type varchar(50),

   -- the date/time on which the file was added
   us_timestamp varbinary(14) NOT NULL,

   us_status varchar(50) NOT NULL,

   -- chunk counter starts at 0, current offset is stored in us_size
   us_chunk_inx int unsigned NULL,

   -- Serialized file properties from FSFile::getProps()
   us_props blob,

   -- file size in bytes
   us_size int unsigned NOT NULL,
   -- this hash comes from FSFile::getSha1Base36(), and is 31 characters
   us_sha1 varchar(31) NOT NULL,
   us_mime varchar(255),
   -- Media type as defined by the MEDIATYPE_xxx constants, should duplicate definition in the image table
   us_media_type ENUM("UNKNOWN", "BITMAP", "DRAWING", "AUDIO", "VIDEO", "MULTIMEDIA", "OFFICE", "TEXT", "EXECUTABLE", "ARCHIVE", "3D") default NULL,
   -- image-specific properties
   us_image_width int unsigned,
   us_image_height int unsigned,
   us_image_bits smallint unsigned

 ) /*$wgDBTableOptions*/;

 -- sometimes there's a delete for all of a user's stuff.
 CREATE INDEX /*i*/us_user ON /*_*/uploadstash (us_user);
 -- pick out files by key, enforce key uniqueness
 CREATE UNIQUE INDEX /*i*/us_key ON /*_*/uploadstash (us_key);
 -- the abandoned upload cleanup script needs this
 CREATE INDEX /*i*/us_timestamp ON /*_*/uploadstash (us_timestamp);


 --
 -- Primarily a summary table for Special:Recentchanges,
 -- this table contains some additional info on edits from
 -- the last few days, see Article::editUpdates()
 --
 CREATE TABLE /*_*/recentchanges (
   rc_id int NOT NULL PRIMARY KEY AUTO_INCREMENT,
   rc_timestamp varbinary(14) NOT NULL default '',

   -- As in revision
   rc_actor bigint unsigned NOT NULL,

   -- When pages are renamed, their RC entries do _not_ change.
   rc_namespace int NOT NULL default 0,
   rc_title varchar(255) binary NOT NULL default '',

   -- as in revision...
   rc_comment_id bigint unsigned NOT NULL,
   rc_minor tinyint unsigned NOT NULL default 0,

   -- Edits by user accounts with the 'bot' rights key are
   -- marked with a 1 here, and will be hidden from the
   -- default view.
   rc_bot tinyint unsigned NOT NULL default 0,

   -- Set if this change corresponds to a page creation
   rc_new tinyint unsigned NOT NULL default 0,

   -- Key to page_id (was cur_id prior to 1.5).
   -- This will keep links working after moves while
   -- retaining the at-the-time name in the changes list.
   rc_cur_id int unsigned NOT NULL default 0,

   -- rev_id of the given revision
   rc_this_oldid int unsigned NOT NULL default 0,

   -- rev_id of the prior revision, for generating diff links.
   rc_last_oldid int unsigned NOT NULL default 0,

   -- The type of change entry (RC_EDIT,RC_NEW,RC_LOG,RC_EXTERNAL)
   rc_type tinyint unsigned NOT NULL default 0,

   -- The source of the change entry (replaces rc_type)
   -- default of '' is temporary, needed for initial migration
   rc_source varchar(16) binary not null default '',

   -- If the Recent Changes Patrol option is enabled,
   -- users may mark edits as having been reviewed to
   -- remove a warning flag on the RC list.
   -- A value of 1 indicates the page has been reviewed.
   rc_patrolled tinyint unsigned NOT NULL default 0,

   -- Recorded IP address the edit was made from, if the
   -- $wgPutIPinRC option is enabled.
   rc_ip varbinary(40) NOT NULL default '',

   -- Text length in characters before
   -- and after the edit
   rc_old_len int,
   rc_new_len int,

   -- Visibility of recent changes items, bitfield
   rc_deleted tinyint unsigned NOT NULL default 0,

   -- Value corresponding to log_id, specific log entries
   rc_logid int unsigned NOT NULL default 0,
   -- Store log type info here, or null
   rc_log_type varbinary(255) NULL default NULL,
   -- Store log action or null
   rc_log_action varbinary(255) NULL default NULL,
   -- Log params
   rc_params blob NULL
 ) /*$wgDBTableOptions*/;

 -- Special:Recentchanges
 CREATE INDEX /*i*/rc_timestamp ON /*_*/recentchanges (rc_timestamp);

 -- Special:Watchlist
 CREATE INDEX /*i*/rc_namespace_title_timestamp ON /*_*/recentchanges (rc_namespace, rc_title, rc_timestamp);

 -- Special:Recentchangeslinked when finding changes in pages linked from a page
 CREATE INDEX /*i*/rc_cur_id ON /*_*/recentchanges (rc_cur_id);

 -- Special:Newpages
 CREATE INDEX /*i*/new_name_timestamp ON /*_*/recentchanges (rc_new,rc_namespace,rc_timestamp);

 -- Blank unless $wgPutIPinRC=true (false at WMF), possibly used by extensions,
 -- but mostly replaced by CheckUser.
 CREATE INDEX /*i*/rc_ip ON /*_*/recentchanges (rc_ip);

 -- Probably intended for Special:NewPages namespace filter
 CREATE INDEX /*i*/rc_ns_actor ON /*_*/recentchanges (rc_namespace, rc_actor);

 -- SiteStats active user count, Special:ActiveUsers, Special:NewPages user filter
 CREATE INDEX /*i*/rc_actor ON /*_*/recentchanges (rc_actor, rc_timestamp);

 -- ApiQueryRecentChanges (T140108)
 CREATE INDEX /*i*/rc_name_type_patrolled_timestamp ON /*_*/recentchanges (rc_namespace, rc_type, rc_patrolled, rc_timestamp);

 -- Article.php and friends (T139012)
 CREATE INDEX /*i*/rc_this_oldid ON /*_*/recentchanges (rc_this_oldid);

 CREATE TABLE /*_*/watchlist (
   wl_id int unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,
   -- Key to user.user_id
   wl_user int unsigned NOT NULL,

   -- Key to page_namespace/page_title
   -- Note that users may watch pages which do not exist yet,
   -- or existed in the past but have been deleted.
   wl_namespace int NOT NULL default 0,
   wl_title varchar(255) binary NOT NULL default '',

   -- Timestamp used to send notification e-mails and show "updated since last visit" markers on
   -- history and recent changes / watchlist. Set to NULL when the user visits the latest revision
   -- of the page, which means that they should be sent an e-mail on the next change.
   wl_notificationtimestamp varbinary(14)

 ) /*$wgDBTableOptions*/;

 -- Special:Watchlist
 CREATE UNIQUE INDEX /*i*/wl_user ON /*_*/watchlist (wl_user, wl_namespace, wl_title);

 -- Special:Movepage (WatchedItemStore::duplicateEntry)
 CREATE INDEX /*i*/namespace_title ON /*_*/watchlist (wl_namespace, wl_title);

 -- ApiQueryWatchlistRaw changed filter
 CREATE INDEX /*i*/wl_user_notificationtimestamp ON /*_*/watchlist (wl_user, wl_notificationtimestamp);


 --
 -- When using the default MySQL search backend, page titles
 -- and text are munged to strip markup, do Unicode case folding,
 -- and prepare the result for MySQL's fulltext index.
 --
 -- This table must be MyISAM; InnoDB does not support the needed
 -- fulltext index.
 --
 CREATE TABLE /*_*/searchindex (
   -- Key to page_id
   si_page int unsigned NOT NULL,

   -- Munged version of title
   si_title varchar(255) NOT NULL default '',

   -- Munged version of body text
   si_text mediumtext NOT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=utf8;

 CREATE UNIQUE INDEX /*i*/si_page ON /*_*/searchindex (si_page);
 CREATE FULLTEXT INDEX /*i*/si_title ON /*_*/searchindex (si_title);
 CREATE FULLTEXT INDEX /*i*/si_text ON /*_*/searchindex (si_text);


 --
 -- Recognized interwiki link prefixes
 --
 CREATE TABLE /*_*/interwiki (
   -- The interwiki prefix, (e.g. "Meatball", or the language prefix "de")
   iw_prefix varchar(32) NOT NULL PRIMARY KEY,

   -- The URL of the wiki, with "$1" as a placeholder for an article name.
   -- Any spaces in the name will be transformed to underscores before
   -- insertion.
   iw_url blob NOT NULL,

   -- The URL of the file api.php
   iw_api blob NOT NULL,

   -- The name of the database (for a connection to be established with LBFactory::getMainLB( 'wikiid' ))
   iw_wikiid varchar(64) NOT NULL,

   -- A boolean value indicating whether the wiki is in this project
   -- (used, for example, to detect redirect loops)
   iw_local bool NOT NULL,

   -- Boolean value indicating whether interwiki transclusions are allowed.
   iw_trans tinyint NOT NULL default 0
 ) /*$wgDBTableOptions*/;


 --
 -- Used for caching expensive grouped queries
 --
 CREATE TABLE /*_*/querycache (
   -- A key name, generally the base name of of the special page.
   qc_type varbinary(32) NOT NULL,

   -- Some sort of stored value. Sizes, counts...
   qc_value int unsigned NOT NULL default 0,

   -- Target namespace+title
   qc_namespace int NOT NULL default 0,
   qc_title varchar(255) binary NOT NULL default ''
 ) /*$wgDBTableOptions*/;

 CREATE INDEX /*i*/qc_type ON /*_*/querycache (qc_type,qc_value);


 --
 -- For a few generic cache operations if not using Memcached
 --
 CREATE TABLE /*_*/objectcache (
   keyname varbinary(255) NOT NULL default '' PRIMARY KEY,
   value mediumblob,
   exptime datetime
 ) /*$wgDBTableOptions*/;
 CREATE INDEX /*i*/exptime ON /*_*/objectcache (exptime);


 CREATE TABLE /*_*/logging (
   -- Log ID, for referring to this specific log entry, probably for deletion and such.
   log_id int unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,

   -- Symbolic keys for the general log type and the action type
   -- within the log. The output format will be controlled by the
   -- action field, but only the type controls categorization.
   log_type varbinary(32) NOT NULL default '',
   log_action varbinary(32) NOT NULL default '',

   -- Timestamp. Duh.
   log_timestamp binary(14) NOT NULL default '19700101000000',

   -- The actor who performed this action
   log_actor bigint unsigned NOT NULL,

   -- Key to the page affected. Where a user is the target,
   -- this will point to the user page.
   log_namespace int NOT NULL default 0,
   log_title varchar(255) binary NOT NULL default '',
   log_page int unsigned NULL,

   -- Key to comment_id. Comment summarizing the change.
   log_comment_id bigint unsigned NOT NULL,

   -- miscellaneous parameters:
   -- LF separated list (old system) or serialized PHP array (new system)
   log_params blob NOT NULL,

   -- rev_deleted for logs
   log_deleted tinyint unsigned NOT NULL default 0
 ) /*$wgDBTableOptions*/;

 -- Special:Log type filter
 CREATE INDEX /*i*/type_time ON /*_*/logging (log_type, log_timestamp);

 -- Special:Log performer filter
 CREATE INDEX /*i*/actor_time ON /*_*/logging (log_actor, log_timestamp);

 -- Special:Log title filter, log extract
 CREATE INDEX /*i*/page_time ON /*_*/logging (log_namespace, log_title, log_timestamp);

 -- Special:Log unfiltered
 CREATE INDEX /*i*/times ON /*_*/logging (log_timestamp);

 -- Special:Log filter by performer and type
 CREATE INDEX /*i*/log_actor_type_time ON /*_*/logging (log_actor, log_type, log_timestamp);

 -- Apparently just used for a few maintenance pages (findMissingFiles.php, Flow).
 -- Could be removed?
 CREATE INDEX /*i*/log_page_id_time ON /*_*/logging (log_page,log_timestamp);

 -- Special:Log action filter
 CREATE INDEX /*i*/log_type_action ON /*_*/logging (log_type, log_action, log_timestamp);


 CREATE TABLE /*_*/log_search (
   -- The type of ID (rev ID, log ID, rev timestamp, username)
   ls_field varbinary(32) NOT NULL,
   -- The value of the ID
   ls_value varchar(255) NOT NULL,
   -- Key to log_id
   ls_log_id int unsigned NOT NULL default 0,
   PRIMARY KEY (ls_field,ls_value,ls_log_id)
 ) /*$wgDBTableOptions*/;
 CREATE INDEX /*i*/ls_log_id ON /*_*/log_search (ls_log_id);


 -- Jobs performed by parallel apache threads or a command-line daemon
 CREATE TABLE /*_*/job (
   job_id int unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,

   -- Command name
   -- Limited to 60 to prevent key length overflow
   job_cmd varbinary(60) NOT NULL default '',

   -- Namespace and title to act on
   -- Should be 0 and '' if the command does not operate on a title
   job_namespace int NOT NULL,
   job_title varchar(255) binary NOT NULL,

   -- Timestamp of when the job was inserted
   -- NULL for jobs added before addition of the timestamp
   job_timestamp varbinary(14) NULL default NULL,

   -- Any other parameters to the command
   -- Stored as a PHP serialized array, or an empty string if there are no parameters
   job_params mediumblob NOT NULL,

   -- Random, non-unique, number used for job acquisition (for lock concurrency)
   job_random integer unsigned NOT NULL default 0,

   -- The number of times this job has been locked
   job_attempts integer unsigned NOT NULL default 0,

   -- Field that conveys process locks on rows via process UUIDs
   job_token varbinary(32) NOT NULL default '',

   -- Timestamp when the job was locked
   job_token_timestamp varbinary(14) NULL default NULL,

   -- Base 36 SHA1 of the job parameters relevant to detecting duplicates
   job_sha1 varbinary(32) NOT NULL default ''
 ) /*$wgDBTableOptions*/;

 CREATE INDEX /*i*/job_sha1 ON /*_*/job (job_sha1);
 CREATE INDEX /*i*/job_cmd_token ON /*_*/job (job_cmd,job_token,job_random);
 CREATE INDEX /*i*/job_cmd_token_id ON /*_*/job (job_cmd,job_token,job_id);
 CREATE INDEX /*i*/job_cmd ON /*_*/job (job_cmd, job_namespace, job_title, job_params(128));
 CREATE INDEX /*i*/job_timestamp ON /*_*/job (job_timestamp);


 -- Details of updates to cached special pages
 CREATE TABLE /*_*/querycache_info (
   -- Special page name
   -- Corresponds to a qc_type value
   qci_type varbinary(32) NOT NULL default '' PRIMARY KEY,

   -- Timestamp of last update
   qci_timestamp binary(14) NOT NULL default '19700101000000'
 ) /*$wgDBTableOptions*/;


 -- For each redirect, this table contains exactly one row defining its target
 CREATE TABLE /*_*/redirect (
   -- Key to the page_id of the redirect page
   rd_from int unsigned NOT NULL default 0 PRIMARY KEY,

   -- Key to page_namespace/page_title of the target page.
   -- The target page may or may not exist, and due to renames
   -- and deletions may refer to different page records as time
   -- goes by.
   rd_namespace int NOT NULL default 0,
   rd_title varchar(255) binary NOT NULL default '',
   rd_interwiki varchar(32) default NULL,
   rd_fragment varchar(255) binary default NULL
 ) /*$wgDBTableOptions*/;

 CREATE INDEX /*i*/rd_ns_title ON /*_*/redirect (rd_namespace,rd_title,rd_from);


 -- Used for caching expensive grouped queries that need two links (for example double-redirects)
 CREATE TABLE /*_*/querycachetwo (
   -- A key name, generally the base name of of the special page.
   qcc_type varbinary(32) NOT NULL,

   -- Some sort of stored value. Sizes, counts...
   qcc_value int unsigned NOT NULL default 0,

   -- Target namespace+title
   qcc_namespace int NOT NULL default 0,
   qcc_title varchar(255) binary NOT NULL default '',

   -- Target namespace+title2
   qcc_namespacetwo int NOT NULL default 0,
   qcc_titletwo varchar(255) binary NOT NULL default ''
 ) /*$wgDBTableOptions*/;

 CREATE INDEX /*i*/qcc_type ON /*_*/querycachetwo (qcc_type,qcc_value);
 CREATE INDEX /*i*/qcc_title ON /*_*/querycachetwo (qcc_type,qcc_namespace,qcc_title);
 CREATE INDEX /*i*/qcc_titletwo ON /*_*/querycachetwo (qcc_type,qcc_namespacetwo,qcc_titletwo);


 -- Used for storing page restrictions (i.e. protection levels)
 CREATE TABLE /*_*/page_restrictions (
   -- Field for an ID for this restrictions row (sort-key for Special:ProtectedPages)
   pr_id int unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,
   -- Page to apply restrictions to (Foreign Key to page).
   pr_page int NOT NULL,
   -- The protection type (edit, move, etc)
   pr_type varbinary(60) NOT NULL,
   -- The protection level (Sysop, autoconfirmed, etc)
   pr_level varbinary(60) NOT NULL,
   -- Whether or not to cascade the protection down to pages transcluded.
   pr_cascade tinyint NOT NULL,
   -- Field for future support of per-user restriction.
   pr_user int unsigned NULL,
   -- Field for time-limited protection.
   pr_expiry varbinary(14) NULL
 ) /*$wgDBTableOptions*/;

 CREATE UNIQUE INDEX /*i*/pr_pagetype ON /*_*/page_restrictions (pr_page,pr_type);
 CREATE INDEX /*i*/pr_typelevel ON /*_*/page_restrictions (pr_type,pr_level);
 CREATE INDEX /*i*/pr_level ON /*_*/page_restrictions (pr_level);
 CREATE INDEX /*i*/pr_cascade ON /*_*/page_restrictions (pr_cascade);


 -- Protected titles - nonexistent pages that have been protected
 CREATE TABLE /*_*/protected_titles (
   pt_namespace int NOT NULL,
   pt_title varchar(255) binary NOT NULL,
   pt_user int unsigned NOT NULL,
   pt_reason_id bigint unsigned NOT NULL,
   pt_timestamp binary(14) NOT NULL,
   pt_expiry varbinary(14) NOT NULL default '',
   pt_create_perm varbinary(60) NOT NULL,

   PRIMARY KEY (pt_namespace,pt_title)
 ) /*$wgDBTableOptions*/;

 CREATE INDEX /*i*/pt_timestamp ON /*_*/protected_titles (pt_timestamp);


 -- Name/value pairs indexed by page_id
 CREATE TABLE /*_*/page_props (
   pp_page int NOT NULL,
   pp_propname varbinary(60) NOT NULL,
   pp_value blob NOT NULL,
   pp_sortkey float DEFAULT NULL,

   PRIMARY KEY (pp_page,pp_propname)
 ) /*$wgDBTableOptions*/;

 CREATE UNIQUE INDEX /*i*/pp_propname_page ON /*_*/page_props (pp_propname,pp_page);
 CREATE UNIQUE INDEX /*i*/pp_propname_sortkey_page ON /*_*/page_props (pp_propname,pp_sortkey,pp_page);

 -- A table to log updates, one text key row per update.
 CREATE TABLE /*_*/updatelog (
   ul_key varchar(255) NOT NULL PRIMARY KEY,
   ul_value blob
 ) /*$wgDBTableOptions*/;


 -- A table to track tags for revisions, logs and recent changes.
 CREATE TABLE /*_*/change_tag (
   ct_id int unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,
   -- RCID for the change
   ct_rc_id int NULL,
   -- LOGID for the change
   ct_log_id int unsigned NULL,
   -- REVID for the change
   ct_rev_id int unsigned NULL,
   -- Parameters for the tag; used by some extensions
   ct_params blob NULL,
   -- Foreign key to change_tag_def row
   ct_tag_id int unsigned NOT NULL
 ) /*$wgDBTableOptions*/;


 CREATE UNIQUE INDEX /*i*/change_tag_rc_tag_id ON /*_*/change_tag (ct_rc_id,ct_tag_id);
 CREATE UNIQUE INDEX /*i*/change_tag_log_tag_id ON /*_*/change_tag (ct_log_id,ct_tag_id);
 CREATE UNIQUE INDEX /*i*/change_tag_rev_tag_id ON /*_*/change_tag (ct_rev_id,ct_tag_id);
 -- Covering index, so we can pull all the info only out of the index.
 CREATE INDEX /*i*/change_tag_tag_id_id ON /*_*/change_tag (ct_tag_id,ct_rc_id,ct_rev_id,ct_log_id);


 -- Table for storing localisation data
 CREATE TABLE /*_*/l10n_cache (
   -- Language code
   lc_lang varbinary(32) NOT NULL,
   -- Cache key
   lc_key varchar(255) NOT NULL,
   -- Value
   lc_value mediumblob NOT NULL,
   PRIMARY KEY (lc_lang, lc_key)
 ) /*$wgDBTableOptions*/;

 -- Table caching which local files a module depends on that aren't
 -- registered directly, used for fast retrieval of file dependency.
 -- Currently only used for tracking images that CSS depends on
 CREATE TABLE /*_*/module_deps (
   -- Module name
   md_module varbinary(255) NOT NULL,
   -- Module context vary (includes skin and language; called "md_skin" for legacy reasons)
   md_skin varbinary(32) NOT NULL,
   -- JSON blob with file dependencies
   md_deps mediumblob NOT NULL,
   PRIMARY KEY (md_module,md_skin)
 ) /*$wgDBTableOptions*/;

 -- Holds all the sites known to the wiki.
 CREATE TABLE /*_*/sites (
   -- Numeric id of the site
   site_id                    INT UNSIGNED        NOT NULL PRIMARY KEY AUTO_INCREMENT,

   -- Global identifier for the site, ie 'enwiktionary'
   site_global_key            varbinary(32)       NOT NULL,

   -- Type of the site, ie 'mediawiki'
   site_type                  varbinary(32)       NOT NULL,

   -- Group of the site, ie 'wikipedia'
   site_group                 varbinary(32)       NOT NULL,

   -- Source of the site data, ie 'local', 'wikidata', 'my-magical-repo'
   site_source                varbinary(32)       NOT NULL,

   -- Language code of the sites primary language.
   site_language              varbinary(32)       NOT NULL,

   -- Protocol of the site, ie 'http://', 'irc://', '//'
   -- This field is an index for lookups and is build from type specific data in site_data.
   site_protocol              varbinary(32)       NOT NULL,

   -- Domain of the site in reverse order, ie 'org.mediawiki.www.'
   -- This field is an index for lookups and is build from type specific data in site_data.
   site_domain                VARCHAR(255)        NOT NULL,

   -- Type dependent site data.
   site_data                  BLOB                NOT NULL,

   -- If site.tld/path/key:pageTitle should forward users to  the page on
   -- the actual site, where "key" is the local identifier.
   site_forward              bool                NOT NULL,

   -- Type dependent site config.
   -- For instance if template transclusion should be allowed if it's a MediaWiki.
   site_config               BLOB                NOT NULL
 ) /*$wgDBTableOptions*/;

 CREATE UNIQUE INDEX /*i*/sites_global_key ON /*_*/sites (site_global_key);
 CREATE INDEX /*i*/sites_type ON /*_*/sites (site_type);
 CREATE INDEX /*i*/sites_group ON /*_*/sites (site_group);
 CREATE INDEX /*i*/sites_source ON /*_*/sites (site_source);
 CREATE INDEX /*i*/sites_language ON /*_*/sites (site_language);
 CREATE INDEX /*i*/sites_protocol ON /*_*/sites (site_protocol);
 CREATE INDEX /*i*/sites_domain ON /*_*/sites (site_domain);
 CREATE INDEX /*i*/sites_forward ON /*_*/sites (site_forward);

 -- Links local site identifiers to their corresponding site.
 CREATE TABLE /*_*/site_identifiers (
   -- Key on site.site_id
   si_site                    INT UNSIGNED        NOT NULL,

   -- local key type, ie 'interwiki' or 'langlink'
   si_type                    varbinary(32)       NOT NULL,

   -- local key value, ie 'en' or 'wiktionary'
   si_key                     varbinary(32)       NOT NULL,

   PRIMARY KEY (si_type, si_key)
 ) /*$wgDBTableOptions*/;

 CREATE INDEX /*i*/site_ids_site ON /*_*/site_identifiers (si_site);
 CREATE INDEX /*i*/site_ids_key ON /*_*/site_identifiers (si_key);

 -- Table defining tag names for IDs. Also stores hit counts to avoid expensive queries on change_tag
 CREATE TABLE /*_*/change_tag_def (
     -- Numerical ID of the tag (ct_tag_id refers to this)
     ctd_id int unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,
     -- Symbolic name of the tag (what would previously be put in ct_tag)
     ctd_name varbinary(255) NOT NULL,
     -- Whether this tag was defined manually by a privileged user using Special:Tags
     ctd_user_defined tinyint(1) NOT NULL,
     -- Number of times this tag was used
     ctd_count bigint unsigned NOT NULL default 0
 ) /*$wgDBTableOptions*/;

 CREATE UNIQUE INDEX /*i*/ctd_name ON /*_*/change_tag_def (ctd_name);
 CREATE INDEX /*i*/ctd_count ON /*_*/change_tag_def (ctd_count);
 CREATE INDEX /*i*/ctd_user_defined ON /*_*/change_tag_def (ctd_user_defined);

 -- vim: sw=2 sts=2 et