PostgresUpdater.php

Go to the documentation of this file.

<?php
use Wikimedia\Rdbms\DatabasePostgres;
 
class PostgresUpdater extends DatabaseUpdater {
 
    protected $db;
 
    protected function getCoreUpdateList() {
        return [
            # rename tables 1.7.3
            # r15791 Change reserved word table names "user" and "text"
            [ 'renameTable', 'user', 'mwuser' ],
            [ 'renameTable', 'text', 'pagecontent' ],
            [ 'renameIndex', 'mwuser', 'user_pkey', 'mwuser_pkey' ],
            [ 'renameIndex', 'mwuser', 'user_user_name_key', 'mwuser_user_name_key' ],
            [ 'renameIndex', 'pagecontent', 'text_pkey', 'pagecontent_pkey' ],
 
            # renamed sequences
            [ 'renameSequence', 'ipblocks_ipb_id_val', 'ipblocks_ipb_id_seq' ],
            [ 'renameSequence', 'rev_rev_id_val', 'revision_rev_id_seq' ],
            [ 'renameSequence', 'text_old_id_val', 'text_old_id_seq' ],
            [ 'renameSequence', 'rc_rc_id_seq', 'recentchanges_rc_id_seq' ],
            [ 'renameSequence', 'log_log_id_seq', 'logging_log_id_seq' ],
            [ 'renameSequence', 'pr_id_val', 'page_restrictions_pr_id_seq' ],
            [ 'renameSequence', 'us_id_seq', 'uploadstash_us_id_seq' ],
 
            # since r58263
            [ 'renameSequence', 'category_id_seq', 'category_cat_id_seq' ],
 
            # new sequences if not renamed above
            [ 'addSequence', 'logging', false, 'logging_log_id_seq' ],
            [ 'addSequence', 'page_restrictions', false, 'page_restrictions_pr_id_seq' ],
            [ 'addSequence', 'filearchive', 'fa_id', 'filearchive_fa_id_seq' ],
            [ 'addSequence', 'archive', false, 'archive_ar_id_seq' ],
            [ 'addSequence', 'externallinks', false, 'externallinks_el_id_seq' ],
            [ 'addSequence', 'watchlist', false, 'watchlist_wl_id_seq' ],
            [ 'addSequence', 'change_tag', false, 'change_tag_ct_id_seq' ],
            [ 'addSequence', 'tag_summary', false, 'tag_summary_ts_id_seq' ],
 
            # new tables
            [ 'addTable', 'category', 'patch-category.sql' ],
            [ 'addTable', 'page', 'patch-page.sql' ],
            [ 'addTable', 'querycachetwo', 'patch-querycachetwo.sql' ],
            [ 'addTable', 'page_props', 'patch-page_props.sql' ],
            [ 'addTable', 'page_restrictions', 'patch-page_restrictions.sql' ],
            [ 'addTable', 'profiling', 'patch-profiling.sql' ],
            [ 'addTable', 'protected_titles', 'patch-protected_titles.sql' ],
            [ 'addTable', 'redirect', 'patch-redirect.sql' ],
            [ 'addTable', 'updatelog', 'patch-updatelog.sql' ],
            [ 'addTable', 'change_tag', 'patch-change_tag.sql' ],
            [ 'addTable', 'tag_summary', 'patch-tag_summary.sql' ],
            [ 'addTable', 'valid_tag', 'patch-valid_tag.sql' ],
            [ 'addTable', 'user_properties', 'patch-user_properties.sql' ],
            [ 'addTable', 'log_search', 'patch-log_search.sql' ],
            [ 'addTable', 'l10n_cache', 'patch-l10n_cache.sql' ],
            [ 'addTable', 'iwlinks', 'patch-iwlinks.sql' ],
            [ 'addTable', 'module_deps', 'patch-module_deps.sql' ],
            [ 'addTable', 'uploadstash', 'patch-uploadstash.sql' ],
            [ 'addTable', 'user_former_groups', 'patch-user_former_groups.sql' ],
            [ 'addTable', 'sites', 'patch-sites.sql' ],
            [ 'addTable', 'bot_passwords', 'patch-bot_passwords.sql' ],
 
            # Needed before new field
            [ 'convertArchive2' ],
 
            # new fields
            [ 'addPgField', 'updatelog', 'ul_value', 'TEXT' ],
            [ 'addPgField', 'archive', 'ar_deleted', 'SMALLINT NOT NULL DEFAULT 0' ],
            [ 'addPgField', 'archive', 'ar_len', 'INTEGER' ],
            [ 'addPgField', 'archive', 'ar_page_id', 'INTEGER' ],
            [ 'addPgField', 'archive', 'ar_parent_id', 'INTEGER' ],
            [ 'addPgField', 'archive', 'ar_content_model', 'TEXT' ],
            [ 'addPgField', 'archive', 'ar_content_format', 'TEXT' ],
            [ 'addPgField', 'categorylinks', 'cl_sortkey_prefix', "TEXT NOT NULL DEFAULT ''" ],
            [ 'addPgField', 'categorylinks', 'cl_collation', "TEXT NOT NULL DEFAULT 0" ],
            [ 'addPgField', 'categorylinks', 'cl_type', "TEXT NOT NULL DEFAULT 'page'" ],
            [ 'addPgField', 'image', 'img_sha1', "TEXT NOT NULL DEFAULT ''" ],
            [ 'addPgField', 'ipblocks', 'ipb_allow_usertalk', 'SMALLINT NOT NULL DEFAULT 0' ],
            [ 'addPgField', 'ipblocks', 'ipb_anon_only', 'SMALLINT NOT NULL DEFAULT 0' ],
            [ 'addPgField', 'ipblocks', 'ipb_by_text', "TEXT NOT NULL DEFAULT ''" ],
            [ 'addPgField', 'ipblocks', 'ipb_block_email', 'SMALLINT NOT NULL DEFAULT 0' ],
            [ 'addPgField', 'ipblocks', 'ipb_create_account', 'SMALLINT NOT NULL DEFAULT 1' ],
            [ 'addPgField', 'ipblocks', 'ipb_deleted', 'SMALLINT NOT NULL DEFAULT 0' ],
            [ 'addPgField', 'ipblocks', 'ipb_enable_autoblock', 'SMALLINT NOT NULL DEFAULT 1' ],
            [ 'addPgField', 'ipblocks', 'ipb_parent_block_id',
                'INTEGER DEFAULT NULL REFERENCES ipblocks(ipb_id) ' .
                'ON DELETE SET NULL DEFERRABLE INITIALLY DEFERRED' ],
            [ 'addPgField', 'filearchive', 'fa_deleted', 'SMALLINT NOT NULL DEFAULT 0' ],
            [ 'addPgField', 'filearchive', 'fa_sha1', "TEXT NOT NULL DEFAULT ''" ],
            [ 'addPgField', 'logging', 'log_deleted', 'SMALLINT NOT NULL DEFAULT 0' ],
            [ 'addPgField', 'logging', 'log_id',
                "INTEGER NOT NULL PRIMARY KEY DEFAULT nextval('logging_log_id_seq')" ],
            [ 'addPgField', 'logging', 'log_params', 'TEXT' ],
            [ 'addPgField', 'mwuser', 'user_editcount', 'INTEGER' ],
            [ 'addPgField', 'mwuser', 'user_newpass_time', 'TIMESTAMPTZ' ],
            [ 'addPgField', 'oldimage', 'oi_deleted', 'SMALLINT NOT NULL DEFAULT 0' ],
            [ 'addPgField', 'oldimage', 'oi_major_mime', "TEXT NOT NULL DEFAULT 'unknown'" ],
            [ 'addPgField', 'oldimage', 'oi_media_type', 'TEXT' ],
            [ 'addPgField', 'oldimage', 'oi_metadata', "BYTEA NOT NULL DEFAULT ''" ],
            [ 'addPgField', 'oldimage', 'oi_minor_mime', "TEXT NOT NULL DEFAULT 'unknown'" ],
            [ 'addPgField', 'oldimage', 'oi_sha1', "TEXT NOT NULL DEFAULT ''" ],
            [ 'addPgField', 'page', 'page_content_model', 'TEXT' ],
            [ 'addPgField', 'page_restrictions', 'pr_id',
                "INTEGER NOT NULL UNIQUE DEFAULT nextval('page_restrictions_pr_id_seq')" ],
            [ 'addPgField', 'profiling', 'pf_memory', 'NUMERIC(18,10) NOT NULL DEFAULT 0' ],
            [ 'addPgField', 'recentchanges', 'rc_deleted', 'SMALLINT NOT NULL DEFAULT 0' ],
            [ 'addPgField', 'recentchanges', 'rc_log_action', 'TEXT' ],
            [ 'addPgField', 'recentchanges', 'rc_log_type', 'TEXT' ],
            [ 'addPgField', 'recentchanges', 'rc_logid', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'addPgField', 'recentchanges', 'rc_new_len', 'INTEGER' ],
            [ 'addPgField', 'recentchanges', 'rc_old_len', 'INTEGER' ],
            [ 'addPgField', 'recentchanges', 'rc_params', 'TEXT' ],
            [ 'addPgField', 'redirect', 'rd_interwiki', 'TEXT NULL' ],
            [ 'addPgField', 'redirect', 'rd_fragment', 'TEXT NULL' ],
            [ 'addPgField', 'revision', 'rev_deleted', 'SMALLINT NOT NULL DEFAULT 0' ],
            [ 'addPgField', 'revision', 'rev_len', 'INTEGER' ],
            [ 'addPgField', 'revision', 'rev_parent_id', 'INTEGER DEFAULT NULL' ],
            [ 'addPgField', 'revision', 'rev_content_model', 'TEXT' ],
            [ 'addPgField', 'revision', 'rev_content_format', 'TEXT' ],
            [ 'addPgField', 'site_stats', 'ss_active_users', "INTEGER DEFAULT '-1'" ],
            [ 'addPgField', 'user_newtalk', 'user_last_timestamp', 'TIMESTAMPTZ' ],
            [ 'addPgField', 'logging', 'log_user_text', "TEXT NOT NULL DEFAULT ''" ],
            [ 'addPgField', 'logging', 'log_page', 'INTEGER' ],
            [ 'addPgField', 'interwiki', 'iw_api', "TEXT NOT NULL DEFAULT ''" ],
            [ 'addPgField', 'interwiki', 'iw_wikiid', "TEXT NOT NULL DEFAULT ''" ],
            [ 'addPgField', 'revision', 'rev_sha1', "TEXT NOT NULL DEFAULT ''" ],
            [ 'addPgField', 'archive', 'ar_sha1', "TEXT NOT NULL DEFAULT ''" ],
            [ 'addPgField', 'uploadstash', 'us_chunk_inx', "INTEGER NULL" ],
            [ 'addPgField', 'job', 'job_timestamp', "TIMESTAMPTZ" ],
            [ 'addPgField', 'job', 'job_random', "INTEGER NOT NULL DEFAULT 0" ],
            [ 'addPgField', 'job', 'job_attempts', "INTEGER NOT NULL DEFAULT 0" ],
            [ 'addPgField', 'job', 'job_token', "TEXT NOT NULL DEFAULT ''" ],
            [ 'addPgField', 'job', 'job_token_timestamp', "TIMESTAMPTZ" ],
            [ 'addPgField', 'job', 'job_sha1', "TEXT NOT NULL DEFAULT ''" ],
            [ 'addPgField', 'archive', 'ar_id',
                "INTEGER NOT NULL PRIMARY KEY DEFAULT nextval('archive_ar_id_seq')" ],
            [ 'addPgField', 'externallinks', 'el_id',
                "INTEGER NOT NULL PRIMARY KEY DEFAULT nextval('externallinks_el_id_seq')" ],
            [ 'addPgField', 'uploadstash', 'us_props', "BYTEA" ],
 
            # type changes
            [ 'changeField', 'archive', 'ar_deleted', 'smallint', '' ],
            [ 'changeField', 'archive', 'ar_minor_edit', 'smallint',
                'ar_minor_edit::smallint DEFAULT 0' ],
            [ 'changeField', 'filearchive', 'fa_deleted', 'smallint', '' ],
            [ 'changeField', 'filearchive', 'fa_height', 'integer', '' ],
            [ 'changeField', 'filearchive', 'fa_metadata', 'bytea', "decode(fa_metadata,'escape')" ],
            [ 'changeField', 'filearchive', 'fa_size', 'integer', '' ],
            [ 'changeField', 'filearchive', 'fa_width', 'integer', '' ],
            [ 'changeField', 'filearchive', 'fa_storage_group', 'text', '' ],
            [ 'changeField', 'filearchive', 'fa_storage_key', 'text', '' ],
            [ 'changeField', 'image', 'img_metadata', 'bytea', "decode(img_metadata,'escape')" ],
            [ 'changeField', 'image', 'img_size', 'integer', '' ],
            [ 'changeField', 'image', 'img_width', 'integer', '' ],
            [ 'changeField', 'image', 'img_height', 'integer', '' ],
            [ 'changeField', 'interwiki', 'iw_local', 'smallint', 'iw_local::smallint' ],
            [ 'changeField', 'interwiki', 'iw_trans', 'smallint', 'iw_trans::smallint DEFAULT 0' ],
            [ 'changeField', 'ipblocks', 'ipb_auto', 'smallint', 'ipb_auto::smallint DEFAULT 0' ],
            [ 'changeField', 'ipblocks', 'ipb_anon_only', 'smallint',
                "CASE WHEN ipb_anon_only=' ' THEN 0 ELSE ipb_anon_only::smallint END DEFAULT 0" ],
            [ 'changeField', 'ipblocks', 'ipb_create_account', 'smallint',
                "CASE WHEN ipb_create_account=' ' THEN 0 ELSE ipb_create_account::smallint END DEFAULT 1" ],
            [ 'changeField', 'ipblocks', 'ipb_enable_autoblock', 'smallint',
                "CASE WHEN ipb_enable_autoblock=' ' THEN 0 ELSE ipb_enable_autoblock::smallint END DEFAULT 1" ],
            [ 'changeField', 'ipblocks', 'ipb_block_email', 'smallint',
                "CASE WHEN ipb_block_email=' ' THEN 0 ELSE ipb_block_email::smallint END DEFAULT 0" ],
            [ 'changeField', 'ipblocks', 'ipb_address', 'text', 'ipb_address::text' ],
            [ 'changeField', 'ipblocks', 'ipb_deleted', 'smallint', 'ipb_deleted::smallint DEFAULT 0' ],
            [ 'changeField', 'mwuser', 'user_token', 'text', '' ],
            [ 'changeField', 'mwuser', 'user_email_token', 'text', '' ],
            [ 'changeField', 'objectcache', 'keyname', 'text', '' ],
            [ 'changeField', 'oldimage', 'oi_height', 'integer', '' ],
            [ 'changeField', 'oldimage', 'oi_metadata', 'bytea', "decode(img_metadata,'escape')" ],
            [ 'changeField', 'oldimage', 'oi_size', 'integer', '' ],
            [ 'changeField', 'oldimage', 'oi_width', 'integer', '' ],
            [ 'changeField', 'page', 'page_is_redirect', 'smallint',
                'page_is_redirect::smallint DEFAULT 0' ],
            [ 'changeField', 'page', 'page_is_new', 'smallint', 'page_is_new::smallint DEFAULT 0' ],
            [ 'changeField', 'querycache', 'qc_value', 'integer', '' ],
            [ 'changeField', 'querycachetwo', 'qcc_value', 'integer', '' ],
            [ 'changeField', 'recentchanges', 'rc_bot', 'smallint', 'rc_bot::smallint DEFAULT 0' ],
            [ 'changeField', 'recentchanges', 'rc_deleted', 'smallint', '' ],
            [ 'changeField', 'recentchanges', 'rc_minor', 'smallint', 'rc_minor::smallint DEFAULT 0' ],
            [ 'changeField', 'recentchanges', 'rc_new', 'smallint', 'rc_new::smallint DEFAULT 0' ],
            [ 'changeField', 'recentchanges', 'rc_type', 'smallint', 'rc_type::smallint DEFAULT 0' ],
            [ 'changeField', 'recentchanges', 'rc_patrolled', 'smallint',
                'rc_patrolled::smallint DEFAULT 0' ],
            [ 'changeField', 'revision', 'rev_deleted', 'smallint', 'rev_deleted::smallint DEFAULT 0' ],
            [ 'changeField', 'revision', 'rev_minor_edit', 'smallint',
                'rev_minor_edit::smallint DEFAULT 0' ],
            [ 'changeField', 'templatelinks', 'tl_namespace', 'smallint', 'tl_namespace::smallint' ],
            [ 'changeField', 'user_newtalk', 'user_ip', 'text', 'host(user_ip)' ],
            [ 'changeField', 'uploadstash', 'us_image_bits', 'smallint', '' ],
            [ 'changeField', 'profiling', 'pf_time', 'float', '' ],
            [ 'changeField', 'profiling', 'pf_memory', 'float', '' ],
 
            # null changes
            [ 'changeNullableField', 'oldimage', 'oi_bits', 'NULL' ],
            [ 'changeNullableField', 'oldimage', 'oi_timestamp', 'NULL' ],
            [ 'changeNullableField', 'oldimage', 'oi_major_mime', 'NULL' ],
            [ 'changeNullableField', 'oldimage', 'oi_minor_mime', 'NULL' ],
            [ 'changeNullableField', 'image', 'img_metadata', 'NOT NULL' ],
            [ 'changeNullableField', 'filearchive', 'fa_metadata', 'NOT NULL' ],
            [ 'changeNullableField', 'recentchanges', 'rc_cur_id', 'NULL' ],
            [ 'changeNullableField', 'recentchanges', 'rc_cur_time', 'NULL' ],
 
            [ 'checkOiDeleted' ],
 
            # New indexes
            [ 'addPgIndex', 'archive', 'archive_user_text', '(ar_user_text)' ],
            [ 'addPgIndex', 'image', 'img_sha1', '(img_sha1)' ],
            [ 'addPgIndex', 'ipblocks', 'ipb_parent_block_id', '(ipb_parent_block_id)' ],
            [ 'addPgIndex', 'oldimage', 'oi_sha1', '(oi_sha1)' ],
            [ 'addPgIndex', 'page', 'page_mediawiki_title', '(page_title) WHERE page_namespace = 8' ],
            [ 'addPgIndex', 'pagelinks', 'pagelinks_title', '(pl_title)' ],
            [ 'addPgIndex', 'page_props', 'pp_propname_page', '(pp_propname, pp_page)' ],
            [ 'addPgIndex', 'revision', 'rev_text_id_idx', '(rev_text_id)' ],
            [ 'addPgIndex', 'recentchanges', 'rc_timestamp_bot', '(rc_timestamp) WHERE rc_bot = 0' ],
            [ 'addPgIndex', 'templatelinks', 'templatelinks_from', '(tl_from)' ],
            [ 'addPgIndex', 'watchlist', 'wl_user', '(wl_user)' ],
            [ 'addPgIndex', 'watchlist', 'wl_user_notificationtimestamp',
                '(wl_user, wl_notificationtimestamp)' ],
            [ 'addPgIndex', 'logging', 'logging_user_type_time',
                '(log_user, log_type, log_timestamp)' ],
            [ 'addPgIndex', 'logging', 'logging_page_id_time', '(log_page,log_timestamp)' ],
            [ 'addPgIndex', 'iwlinks', 'iwl_prefix_from_title', '(iwl_prefix, iwl_from, iwl_title)' ],
            [ 'addPgIndex', 'iwlinks', 'iwl_prefix_title_from', '(iwl_prefix, iwl_title, iwl_from)' ],
            [ 'addPgIndex', 'job', 'job_timestamp_idx', '(job_timestamp)' ],
            [ 'addPgIndex', 'job', 'job_sha1', '(job_sha1)' ],
            [ 'addPgIndex', 'job', 'job_cmd_token', '(job_cmd, job_token, job_random)' ],
            [ 'addPgIndex', 'job', 'job_cmd_token_id', '(job_cmd, job_token, job_id)' ],
            [ 'addPgIndex', 'filearchive', 'fa_sha1', '(fa_sha1)' ],
            [ 'addPgIndex', 'logging', 'logging_user_text_type_time',
                '(log_user_text, log_type, log_timestamp)' ],
            [ 'addPgIndex', 'logging', 'logging_user_text_time', '(log_user_text, log_timestamp)' ],
 
            [ 'checkIndex', 'pagelink_unique', [
                [ 'pl_from', 'int4_ops', 'btree', 0 ],
                [ 'pl_namespace', 'int2_ops', 'btree', 0 ],
                [ 'pl_title', 'text_ops', 'btree', 0 ],
            ],
                'CREATE UNIQUE INDEX pagelink_unique ON pagelinks (pl_from,pl_namespace,pl_title)' ],
            [ 'checkIndex', 'cl_sortkey', [
                [ 'cl_to', 'text_ops', 'btree', 0 ],
                [ 'cl_sortkey', 'text_ops', 'btree', 0 ],
                [ 'cl_from', 'int4_ops', 'btree', 0 ],
            ],
                'CREATE INDEX cl_sortkey ON "categorylinks" ' .
                    'USING "btree" ("cl_to", "cl_sortkey", "cl_from")' ],
            [ 'checkIndex', 'iwl_prefix_title_from', [
                [ 'iwl_prefix', 'text_ops', 'btree', 0 ],
                [ 'iwl_title', 'text_ops', 'btree', 0 ],
                [ 'iwl_from', 'int4_ops', 'btree', 0 ],
            ],
            'CREATE INDEX iwl_prefix_title_from ON "iwlinks" ' .
                'USING "btree" ("iwl_prefix", "iwl_title", "iwl_from")' ],
            [ 'checkIndex', 'logging_times', [
                [ 'log_timestamp', 'timestamptz_ops', 'btree', 0 ],
            ],
            'CREATE INDEX "logging_times" ON "logging" USING "btree" ("log_timestamp")' ],
            [ 'dropPgIndex', 'oldimage', 'oi_name' ],
            [ 'checkIndex', 'oi_name_archive_name', [
                [ 'oi_name', 'text_ops', 'btree', 0 ],
                [ 'oi_archive_name', 'text_ops', 'btree', 0 ],
            ],
            'CREATE INDEX "oi_name_archive_name" ON "oldimage" ' .
                'USING "btree" ("oi_name", "oi_archive_name")' ],
            [ 'checkIndex', 'oi_name_timestamp', [
                [ 'oi_name', 'text_ops', 'btree', 0 ],
                [ 'oi_timestamp', 'timestamptz_ops', 'btree', 0 ],
            ],
            'CREATE INDEX "oi_name_timestamp" ON "oldimage" ' .
                'USING "btree" ("oi_name", "oi_timestamp")' ],
            [ 'checkIndex', 'page_main_title', [
                [ 'page_title', 'text_pattern_ops', 'btree', 0 ],
            ],
            'CREATE INDEX "page_main_title" ON "page" ' .
                'USING "btree" ("page_title" "text_pattern_ops") WHERE ("page_namespace" = 0)' ],
            [ 'checkIndex', 'page_mediawiki_title', [
                [ 'page_title', 'text_pattern_ops', 'btree', 0 ],
            ],
            'CREATE INDEX "page_mediawiki_title" ON "page" ' .
                'USING "btree" ("page_title" "text_pattern_ops") WHERE ("page_namespace" = 8)' ],
            [ 'checkIndex', 'page_project_title', [
                [ 'page_title', 'text_pattern_ops', 'btree', 0 ],
            ],
            'CREATE INDEX "page_project_title" ON "page" ' .
                'USING "btree" ("page_title" "text_pattern_ops") ' .
                'WHERE ("page_namespace" = 4)' ],
            [ 'checkIndex', 'page_talk_title', [
                [ 'page_title', 'text_pattern_ops', 'btree', 0 ],
            ],
            'CREATE INDEX "page_talk_title" ON "page" ' .
                'USING "btree" ("page_title" "text_pattern_ops") ' .
                'WHERE ("page_namespace" = 1)' ],
            [ 'checkIndex', 'page_user_title', [
                [ 'page_title', 'text_pattern_ops', 'btree', 0 ],
            ],
            'CREATE INDEX "page_user_title" ON "page" ' .
                'USING "btree" ("page_title" "text_pattern_ops") WHERE ' .
                '("page_namespace" = 2)' ],
            [ 'checkIndex', 'page_utalk_title', [
                [ 'page_title', 'text_pattern_ops', 'btree', 0 ],
            ],
            'CREATE INDEX "page_utalk_title" ON "page" ' .
                'USING "btree" ("page_title" "text_pattern_ops") ' .
                'WHERE ("page_namespace" = 3)' ],
            [ 'checkIndex', 'ts2_page_text', [
                [ 'textvector', 'tsvector_ops', 'gist', 0 ],
            ],
            'CREATE INDEX "ts2_page_text" ON "pagecontent" USING "gist" ("textvector")' ],
            [ 'checkIndex', 'ts2_page_title', [
                [ 'titlevector', 'tsvector_ops', 'gist', 0 ],
            ],
            'CREATE INDEX "ts2_page_title" ON "page" USING "gist" ("titlevector")' ],
 
            [ 'checkOiNameConstraint' ],
            [ 'checkPageDeletedTrigger' ],
            [ 'checkRevUserFkey' ],
            [ 'dropPgIndex', 'ipblocks', 'ipb_address' ],
            [ 'checkIndex', 'ipb_address_unique', [
                [ 'ipb_address', 'text_ops', 'btree', 0 ],
                [ 'ipb_user', 'int4_ops', 'btree', 0 ],
                [ 'ipb_auto', 'int2_ops', 'btree', 0 ],
                [ 'ipb_anon_only', 'int2_ops', 'btree', 0 ],
            ],
            'CREATE UNIQUE INDEX ipb_address_unique ' .
                'ON ipblocks (ipb_address,ipb_user,ipb_auto,ipb_anon_only)' ],
 
            [ 'checkIwlPrefix' ],
 
            # All FK columns should be deferred
            [ 'changeFkeyDeferrable', 'archive', 'ar_user', 'mwuser(user_id) ON DELETE SET NULL' ],
            [ 'changeFkeyDeferrable', 'categorylinks', 'cl_from', 'page(page_id) ON DELETE CASCADE' ],
            [ 'changeFkeyDeferrable', 'externallinks', 'el_from', 'page(page_id) ON DELETE CASCADE' ],
            [ 'changeFkeyDeferrable', 'filearchive', 'fa_deleted_user',
                'mwuser(user_id) ON DELETE SET NULL' ],
            [ 'changeFkeyDeferrable', 'filearchive', 'fa_user', 'mwuser(user_id) ON DELETE SET NULL' ],
            [ 'changeFkeyDeferrable', 'image', 'img_user', 'mwuser(user_id) ON DELETE SET NULL' ],
            [ 'changeFkeyDeferrable', 'imagelinks', 'il_from', 'page(page_id) ON DELETE CASCADE' ],
            [ 'changeFkeyDeferrable', 'ipblocks', 'ipb_by', 'mwuser(user_id) ON DELETE CASCADE' ],
            [ 'changeFkeyDeferrable', 'ipblocks', 'ipb_user', 'mwuser(user_id) ON DELETE SET NULL' ],
            [ 'changeFkeyDeferrable', 'ipblocks', 'ipb_parent_block_id',
                'ipblocks(ipb_id) ON DELETE SET NULL' ],
            [ 'changeFkeyDeferrable', 'langlinks', 'll_from', 'page(page_id) ON DELETE CASCADE' ],
            [ 'changeFkeyDeferrable', 'logging', 'log_user', 'mwuser(user_id) ON DELETE SET NULL' ],
            [ 'changeFkeyDeferrable', 'oldimage', 'oi_name',
                'image(img_name) ON DELETE CASCADE ON UPDATE CASCADE' ],
            [ 'changeFkeyDeferrable', 'oldimage', 'oi_user', 'mwuser(user_id) ON DELETE SET NULL' ],
            [ 'changeFkeyDeferrable', 'pagelinks', 'pl_from', 'page(page_id) ON DELETE CASCADE' ],
            [ 'changeFkeyDeferrable', 'page_props', 'pp_page', 'page (page_id) ON DELETE CASCADE' ],
            [ 'changeFkeyDeferrable', 'page_restrictions', 'pr_page',
                'page(page_id) ON DELETE CASCADE' ],
            [ 'changeFkeyDeferrable', 'protected_titles', 'pt_user',
                'mwuser(user_id) ON DELETE SET NULL' ],
            [ 'changeFkeyDeferrable', 'recentchanges', 'rc_user',
                'mwuser(user_id) ON DELETE SET NULL' ],
            [ 'changeFkeyDeferrable', 'redirect', 'rd_from', 'page(page_id) ON DELETE CASCADE' ],
            [ 'changeFkeyDeferrable', 'revision', 'rev_page', 'page (page_id) ON DELETE CASCADE' ],
            [ 'changeFkeyDeferrable', 'revision', 'rev_user', 'mwuser(user_id) ON DELETE RESTRICT' ],
            [ 'changeFkeyDeferrable', 'templatelinks', 'tl_from', 'page(page_id) ON DELETE CASCADE' ],
            [ 'changeFkeyDeferrable', 'user_groups', 'ug_user', 'mwuser(user_id) ON DELETE CASCADE' ],
            [ 'changeFkeyDeferrable', 'user_newtalk', 'user_id', 'mwuser(user_id) ON DELETE CASCADE' ],
            [ 'changeFkeyDeferrable', 'user_properties', 'up_user',
                'mwuser(user_id) ON DELETE CASCADE' ],
            [ 'changeFkeyDeferrable', 'watchlist', 'wl_user', 'mwuser(user_id) ON DELETE CASCADE' ],
 
            # r81574
            [ 'addInterwikiType' ],
            # end
            [ 'tsearchFixes' ],
 
            // 1.23
            [ 'addPgField', 'recentchanges', 'rc_source', "TEXT NOT NULL DEFAULT ''" ],
            [ 'addPgField', 'page', 'page_links_updated', "TIMESTAMPTZ NULL" ],
            [ 'addPgField', 'mwuser', 'user_password_expires', 'TIMESTAMPTZ NULL' ],
            [ 'changeFieldPurgeTable', 'l10n_cache', 'lc_value', 'bytea',
                "replace(lc_value,'\','\\\\')::bytea" ],
            // 1.23.9
            [ 'rebuildTextSearch' ],
 
            // 1.24
            [ 'addPgField', 'page_props', 'pp_sortkey', 'float NULL' ],
            [ 'addPgIndex', 'page_props', 'pp_propname_sortkey_page',
                    '( pp_propname, pp_sortkey, pp_page ) WHERE ( pp_sortkey IS NOT NULL )' ],
            [ 'addPgField', 'page', 'page_lang', 'TEXT default NULL' ],
            [ 'addPgField', 'pagelinks', 'pl_from_namespace', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'addPgField', 'templatelinks', 'tl_from_namespace', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'addPgField', 'imagelinks', 'il_from_namespace', 'INTEGER NOT NULL DEFAULT 0' ],
 
            // 1.25
            [ 'dropTable', 'hitcounter' ],
            [ 'dropField', 'site_stats', 'ss_total_views', 'patch-drop-ss_total_views.sql' ],
            [ 'dropField', 'page', 'page_counter', 'patch-drop-page_counter.sql' ],
            [ 'dropFkey', 'recentchanges', 'rc_cur_id' ],
 
            // 1.27
            [ 'dropTable', 'msg_resource_links' ],
            [ 'dropTable', 'msg_resource' ],
            [
                'addPgField', 'watchlist', 'wl_id',
                "INTEGER NOT NULL PRIMARY KEY DEFAULT nextval('watchlist_wl_id_seq')"
            ],
 
            // 1.28
            [ 'addPgIndex', 'recentchanges', 'rc_name_type_patrolled_timestamp',
                '( rc_namespace, rc_type, rc_patrolled, rc_timestamp )' ],
            [ 'addPgField', 'change_tag', 'ct_id',
                "INTEGER NOT NULL PRIMARY KEY DEFAULT nextval('change_tag_ct_id_seq')" ],
            [ 'addPgField', 'tag_summary', 'ts_id',
                "INTEGER NOT NULL PRIMARY KEY DEFAULT nextval('tag_summary_ts_id_seq')" ],
 
            // 1.29
            [ 'addPgField', 'externallinks', 'el_index_60', "BYTEA NOT NULL DEFAULT ''" ],
            [ 'addPgIndex', 'externallinks', 'el_index_60', '( el_index_60, el_id )' ],
            [ 'addPgIndex', 'externallinks', 'el_from_index_60', '( el_from, el_index_60, el_id )' ],
            [ 'addPgField', 'user_groups', 'ug_expiry', "TIMESTAMPTZ NULL" ],
            [ 'addPgIndex', 'user_groups', 'user_groups_expiry', '( ug_expiry )' ],
 
            // 1.30
            [ 'addPgEnumValue', 'media_type', '3D' ],
            [ 'setDefault', 'revision', 'rev_comment', '' ],
            [ 'changeNullableField', 'revision', 'rev_comment', 'NOT NULL', true ],
            [ 'setDefault', 'archive', 'ar_comment', '' ],
            [ 'changeNullableField', 'archive', 'ar_comment', 'NOT NULL', true ],
            [ 'addPgField', 'archive', 'ar_comment_id', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'setDefault', 'ipblocks', 'ipb_reason', '' ],
            [ 'addPgField', 'ipblocks', 'ipb_reason_id', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'setDefault', 'image', 'img_description', '' ],
            [ 'setDefault', 'oldimage', 'oi_description', '' ],
            [ 'changeNullableField', 'oldimage', 'oi_description', 'NOT NULL', true ],
            [ 'addPgField', 'oldimage', 'oi_description_id', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'setDefault', 'filearchive', 'fa_deleted_reason', '' ],
            [ 'changeNullableField', 'filearchive', 'fa_deleted_reason', 'NOT NULL', true ],
            [ 'addPgField', 'filearchive', 'fa_deleted_reason_id', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'setDefault', 'filearchive', 'fa_description', '' ],
            [ 'addPgField', 'filearchive', 'fa_description_id', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'setDefault', 'recentchanges', 'rc_comment', '' ],
            [ 'changeNullableField', 'recentchanges', 'rc_comment', 'NOT NULL', true ],
            [ 'addPgField', 'recentchanges', 'rc_comment_id', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'setDefault', 'logging', 'log_comment', '' ],
            [ 'changeNullableField', 'logging', 'log_comment', 'NOT NULL', true ],
            [ 'addPgField', 'logging', 'log_comment_id', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'setDefault', 'protected_titles', 'pt_reason', '' ],
            [ 'changeNullableField', 'protected_titles', 'pt_reason', 'NOT NULL', true ],
            [ 'addPgField', 'protected_titles', 'pt_reason_id', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'addTable', 'comment', 'patch-comment-table.sql' ],
            [ 'addTable', 'revision_comment_temp', 'patch-revision_comment_temp-table.sql' ],
            // image_comment_temp is no longer needed when upgrading to MW 1.31 or newer,
            // as it is dropped later in the update process as part of 'migrateImageCommentTemp'.
            // File kept on disk and the updater entry here for historical purposes.
            // [ 'addTable', 'image_comment_temp', 'patch-image_comment_temp-table.sql' ],
 
            // This field was added in 1.31, but is put here so it can be used by 'migrateComments'
            [ 'addPgField', 'image', 'img_description_id', 'INTEGER NOT NULL DEFAULT 0' ],
 
            [ 'migrateComments' ],
            [ 'addIndex', 'site_stats', 'site_stats_pkey', 'patch-site_stats-pk.sql' ],
            [ 'addTable', 'ip_changes', 'patch-ip_changes.sql' ],
 
            // 1.31
            [ 'addTable', 'slots', 'patch-slots-table.sql' ],
            [ 'dropPgIndex', 'slots', 'slot_role_inherited' ],
            [ 'dropPgField', 'slots', 'slot_inherited' ],
            [ 'addPgField', 'slots', 'slot_origin', 'INTEGER NOT NULL' ],
            [
                'addPgIndex',
                'slots',
                'slot_revision_origin_role',
                '( slot_revision_id, slot_origin, slot_role_id )',
            ],
            [ 'addTable', 'content', 'patch-content-table.sql' ],
            [ 'addTable', 'content_models', 'patch-content_models-table.sql' ],
            [ 'addTable', 'slot_roles', 'patch-slot_roles-table.sql' ],
            [ 'migrateArchiveText' ],
            [ 'addTable', 'actor', 'patch-actor-table.sql' ],
            [ 'addTable', 'revision_actor_temp', 'patch-revision_actor_temp-table.sql' ],
            [ 'setDefault', 'revision', 'rev_user', 0 ],
            [ 'setDefault', 'revision', 'rev_user_text', '' ],
            [ 'setDefault', 'archive', 'ar_user', 0 ],
            [ 'changeNullableField', 'archive', 'ar_user', 'NOT NULL', true ],
            [ 'setDefault', 'archive', 'ar_user_text', '' ],
            [ 'addPgField', 'archive', 'ar_actor', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'addPgIndex', 'archive', 'archive_actor', '( ar_actor )' ],
            [ 'setDefault', 'ipblocks', 'ipb_by', 0 ],
            [ 'addPgField', 'ipblocks', 'ipb_by_actor', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'setDefault', 'image', 'img_user', 0 ],
            [ 'changeNullableField', 'image', 'img_user', 'NOT NULL', true ],
            [ 'setDefault', 'image', 'img_user_text', '' ],
            [ 'addPgField', 'image', 'img_actor', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'setDefault', 'oldimage', 'oi_user', 0 ],
            [ 'changeNullableField', 'oldimage', 'oi_user', 'NOT NULL', true ],
            [ 'setDefault', 'oldimage', 'oi_user_text', '' ],
            [ 'addPgField', 'oldimage', 'oi_actor', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'setDefault', 'filearchive', 'fa_user', 0 ],
            [ 'changeNullableField', 'filearchive', 'fa_user', 'NOT NULL', true ],
            [ 'setDefault', 'filearchive', 'fa_user_text', '' ],
            [ 'addPgField', 'filearchive', 'fa_actor', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'setDefault', 'recentchanges', 'rc_user', 0 ],
            [ 'changeNullableField', 'recentchanges', 'rc_user', 'NOT NULL', true ],
            [ 'setDefault', 'recentchanges', 'rc_user_text', '' ],
            [ 'addPgField', 'recentchanges', 'rc_actor', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'setDefault', 'logging', 'log_user', 0 ],
            [ 'changeNullableField', 'logging', 'log_user', 'NOT NULL', true ],
            [ 'addPgField', 'logging', 'log_actor', 'INTEGER NOT NULL DEFAULT 0' ],
            [ 'addPgIndex', 'logging', 'logging_actor_time_backwards', '( log_timestamp, log_actor )' ],
            [ 'addPgIndex', 'logging', 'logging_actor_type_time', '( log_actor, log_type, log_timestamp )' ],
            [ 'addPgIndex', 'logging', 'logging_actor_time', '( log_actor, log_timestamp )' ],
            [ 'migrateActors' ],
            [ 'modifyTable', 'site_stats', 'patch-site_stats-modify.sql' ],
            [ 'populateArchiveRevId' ],
            [ 'dropPgIndex', 'recentchanges', 'rc_namespace_title' ],
            [
                'addPgIndex',
                'recentchanges',
                'rc_namespace_title_timestamp', '( rc_namespace, rc_title, rc_timestamp )'
            ],
            [ 'setSequenceOwner', 'mwuser', 'user_id', 'user_user_id_seq' ],
            [ 'setSequenceOwner', 'actor', 'actor_id', 'actor_actor_id_seq' ],
            [ 'setSequenceOwner', 'page', 'page_id', 'page_page_id_seq' ],
            [ 'setSequenceOwner', 'revision', 'rev_id', 'revision_rev_id_seq' ],
            [ 'setSequenceOwner', 'ip_changes', 'ipc_rev_id', 'ip_changes_ipc_rev_id_seq' ],
            [ 'setSequenceOwner', 'pagecontent', 'old_id', 'text_old_id_seq' ],
            [ 'setSequenceOwner', 'comment', 'comment_id', 'comment_comment_id_seq' ],
            [ 'setSequenceOwner', 'page_restrictions', 'pr_id', 'page_restrictions_pr_id_seq' ],
            [ 'setSequenceOwner', 'archive', 'ar_id', 'archive_ar_id_seq' ],
            [ 'setSequenceOwner', 'content', 'content_id', 'content_content_id_seq' ],
            [ 'setSequenceOwner', 'slot_roles', 'role_id', 'slot_roles_role_id_seq' ],
            [ 'setSequenceOwner', 'content_models', 'model_id', 'content_models_model_id_seq' ],
            [ 'setSequenceOwner', 'externallinks', 'el_id', 'externallinks_el_id_seq' ],
            [ 'setSequenceOwner', 'ipblocks', 'ipb_id', 'ipblocks_ipb_id_seq' ],
            [ 'setSequenceOwner', 'filearchive', 'fa_id', 'filearchive_fa_id_seq' ],
            [ 'setSequenceOwner', 'uploadstash', 'us_id', 'uploadstash_us_id_seq' ],
            [ 'setSequenceOwner', 'recentchanges', 'rc_id', 'recentchanges_rc_id_seq' ],
            [ 'setSequenceOwner', 'watchlist', 'wl_id', 'watchlist_wl_id_seq' ],
            [ 'setSequenceOwner', 'logging', 'log_id', 'logging_log_id_seq' ],
            [ 'setSequenceOwner', 'job', 'job_id', 'job_job_id_seq' ],
            [ 'setSequenceOwner', 'category', 'cat_id', 'category_cat_id_seq' ],
            [ 'setSequenceOwner', 'change_tag', 'ct_id', 'change_tag_ct_id_seq' ],
            [ 'setSequenceOwner', 'tag_summary', 'ts_id', 'tag_summary_ts_id_seq' ],
            [ 'setSequenceOwner', 'sites', 'site_id', 'sites_site_id_seq' ],
 
            // 1.32
            [ 'addTable', 'change_tag_def', 'patch-change_tag_def.sql' ],
            [ 'populateExternallinksIndex60' ],
            [ 'dropDefault', 'externallinks', 'el_index_60' ],
            [ 'runMaintenance', DeduplicateArchiveRevId::class, 'maintenance/deduplicateArchiveRevId.php' ],
            [ 'addPgField', 'change_tag', 'ct_tag_id', 'INTEGER NULL' ],
            [
                'addPgIndex',
                'change_tag',
                'change_tag_tag_id_id',
                '( ct_tag_id, ct_rc_id, ct_rev_id, ct_log_id )'
            ],
            [ 'addPgIndex', 'archive', 'ar_revid_uniq', '(ar_rev_id)', 'unique' ],
            [ 'dropPgIndex', 'archive', 'ar_revid' ], // Probably doesn't exist, but do it anyway.
            [ 'populateContentTables' ],
            [ 'addPgIndex', 'logging', 'log_type_action', '( log_type, log_action, log_timestamp )' ],
            [ 'dropPgIndex', 'page_props', 'page_props_propname' ],
            [ 'addIndex', 'interwiki', 'interwiki_pkey', 'patch-interwiki-pk.sql' ],
            [ 'addIndex', 'protected_titles', 'protected_titles_pkey', 'patch-protected_titles-pk.sql' ],
            [ 'addIndex', 'site_identifiers', 'site_identifiers_pkey', 'patch-site_identifiers-pk.sql' ],
            [ 'addPgIndex', 'recentchanges', 'rc_this_oldid', '(rc_this_oldid)' ],
            [ 'dropTable', 'transcache' ],
            [ 'runMaintenance', PopulateChangeTagDef::class, 'maintenance/populateChangeTagDef.php' ],
            [ 'addIndex', 'change_tag', 'change_tag_rc_tag_id',
                'patch-change_tag-change_tag_rc_tag_id.sql' ],
            [ 'addPgField', 'ipblocks', 'ipb_sitewide', 'SMALLINT NOT NULL DEFAULT 1' ],
            [ 'addTable', 'ipblocks_restrictions', 'patch-ipblocks_restrictions-table.sql' ],
            [ 'migrateImageCommentTemp' ],
            [ 'dropPgField', 'category', 'cat_hidden' ],
            [ 'dropPgField', 'site_stats', 'ss_admins' ],
            [ 'dropPgField', 'recentchanges', 'rc_cur_time' ],
        ];
    }
 
    protected function getOldGlobalUpdates() {
        global $wgExtNewTables, $wgExtPGNewFields, $wgExtPGAlteredFields, $wgExtNewIndexes;
 
        $updates = [];
 
        # Add missing extension tables
        foreach ( $wgExtNewTables as $tableRecord ) {
            $updates[] = [
                'addTable', $tableRecord[0], $tableRecord[1], true
            ];
        }
 
        # Add missing extension fields
        foreach ( $wgExtPGNewFields as $fieldRecord ) {
            $updates[] = [
                'addPgField', $fieldRecord[0], $fieldRecord[1],
                $fieldRecord[2]
            ];
        }
 
        # Change altered columns
        foreach ( $wgExtPGAlteredFields as $fieldRecord ) {
            $updates[] = [
                'changeField', $fieldRecord[0], $fieldRecord[1],
                $fieldRecord[2]
            ];
        }
 
        # Add missing extension indexes
        foreach ( $wgExtNewIndexes as $fieldRecord ) {
            $updates[] = [
                'addPgExtIndex', $fieldRecord[0], $fieldRecord[1],
                $fieldRecord[2]
            ];
        }
 
        return $updates;
    }
 
    protected function describeTable( $table ) {
        $q = <<<END
SELECT attname, attnum FROM pg_namespace, pg_class, pg_attribute
    WHERE pg_class.relnamespace = pg_namespace.oid
        AND attrelid=pg_class.oid AND attnum > 0
        AND relname=%s AND nspname=%s
END;
        $res = $this->db->query( sprintf( $q,
            $this->db->addQuotes( $table ),
            $this->db->addQuotes( $this->db->getCoreSchema() ) ) );
        if ( !$res ) {
            return null;
        }
 
        $cols = [];
        foreach ( $res as $r ) {
            $cols[] = [
                "name" => $r[0],
                "ord" => $r[1],
            ];
        }
 
        return $cols;
    }
 
    function describeIndex( $idx ) {
        // first fetch the key (which is a list of columns ords) and
        // the table the index applies to (an oid)
        $q = <<<END
SELECT indkey, indrelid FROM pg_namespace, pg_class, pg_index
    WHERE nspname=%s
        AND pg_class.relnamespace = pg_namespace.oid
        AND relname=%s
        AND indexrelid=pg_class.oid
END;
        $res = $this->db->query(
            sprintf(
                $q,
                $this->db->addQuotes( $this->db->getCoreSchema() ),
                $this->db->addQuotes( $idx )
            )
        );
        if ( !$res ) {
            return null;
        }
        $r = $this->db->fetchRow( $res );
        if ( !$r ) {
            return null;
        }
 
        $indkey = $r[0];
        $relid = intval( $r[1] );
        $indkeys = explode( ' ', $indkey );
 
        $colnames = [];
        foreach ( $indkeys as $rid ) {
            $query = <<<END
SELECT attname FROM pg_class, pg_attribute
    WHERE attrelid=$relid
        AND attnum=%d
        AND attrelid=pg_class.oid
END;
            $r2 = $this->db->query( sprintf( $query, $rid ) );
            if ( !$r2 ) {
                return null;
            }
            $row2 = $this->db->fetchRow( $r2 );
            if ( !$row2 ) {
                return null;
            }
            $colnames[] = $row2[0];
        }
 
        return $colnames;
    }
 
    function fkeyDeltype( $fkey ) {
        $q = <<<END
SELECT confdeltype FROM pg_constraint, pg_namespace
    WHERE connamespace=pg_namespace.oid
        AND nspname=%s
        AND conname=%s;
END;
        $r = $this->db->query(
            sprintf(
                $q,
                $this->db->addQuotes( $this->db->getCoreSchema() ),
                $this->db->addQuotes( $fkey )
            )
        );
        $row = $this->db->fetchRow( $r );
        if ( !$row ) {
            return null;
        }
 
        return $row[0];
    }
 
    function ruleDef( $table, $rule ) {
        $q = <<<END
SELECT definition FROM pg_rules
    WHERE schemaname = %s
        AND tablename = %s
        AND rulename = %s
END;
        $r = $this->db->query(
            sprintf(
                $q,
                $this->db->addQuotes( $this->db->getCoreSchema() ),
                $this->db->addQuotes( $table ),
                $this->db->addQuotes( $rule )
            )
        );
        $row = $this->db->fetchRow( $r );
        if ( !$row ) {
            return null;
        }
        $d = $row[0];
 
        return $d;
    }
 
    protected function addSequence( $table, $pkey, $ns ) {
        if ( !$this->db->sequenceExists( $ns ) ) {
            $this->output( "Creating sequence $ns\n" );
            if ( $pkey !== false ) {
                $this->db->query( "CREATE SEQUENCE $ns OWNED BY $table.$pkey" );
                $this->setDefault( $table, $pkey, '"nextval"(\'"' . $ns . '"\'::"regclass")' );
            } else {
                $this->db->query( "CREATE SEQUENCE $ns" );
            }
        }
    }
 
    protected function dropSequence( $table, $ns ) {
        if ( $this->db->sequenceExists( $ns ) ) {
            $this->output( "Dropping sequence $ns\n" );
            $this->db->query( "DROP SEQUENCE $ns CASCADE" );
        }
    }
 
    protected function renameSequence( $old, $new ) {
        if ( $this->db->sequenceExists( $new ) ) {
            $this->output( "...sequence $new already exists.\n" );
 
            return;
        }
        if ( $this->db->sequenceExists( $old ) ) {
            $this->output( "Renaming sequence $old to $new\n" );
            $this->db->query( "ALTER SEQUENCE $old RENAME TO $new" );
        }
    }
 
    protected function setSequenceOwner( $table, $pkey, $seq ) {
        if ( $this->db->sequenceExists( $seq ) ) {
            $this->output( "Setting sequence $seq owner to $table.$pkey\n" );
            $this->db->query( "ALTER SEQUENCE $seq OWNED BY $table.$pkey" );
        }
    }
 
    protected function renameTable( $old, $new, $patch = false ) {
        if ( $this->db->tableExists( $old ) ) {
            $this->output( "Renaming table $old to $new\n" );
            $old = $this->db->realTableName( $old, "quoted" );
            $new = $this->db->realTableName( $new, "quoted" );
            $this->db->query( "ALTER TABLE $old RENAME TO $new" );
            if ( $patch !== false ) {
                $this->applyPatch( $patch );
            }
        }
    }
 
    protected function renameIndex(
        $table, $old, $new, $skipBothIndexExistWarning = false, $a = false, $b = false
    ) {
        // First requirement: the table must exist
        if ( !$this->db->tableExists( $table, __METHOD__ ) ) {
            $this->output( "...skipping: '$table' table doesn't exist yet.\n" );
 
            return;
        }
 
        // Second requirement: the new index must be missing
        if ( $this->db->indexExists( $table, $new, __METHOD__ ) ) {
            $this->output( "...index $new already set on $table table.\n" );
            if ( !$skipBothIndexExistWarning
                && $this->db->indexExists( $table, $old, __METHOD__ )
            ) {
                $this->output( "...WARNING: $old still exists, despite it has been " .
                    "renamed into $new (which also exists).\n" .
                    "            $old should be manually removed if not needed anymore.\n" );
            }
 
            return;
        }
 
        // Third requirement: the old index must exist
        if ( !$this->db->indexExists( $table, $old, __METHOD__ ) ) {
            $this->output( "...skipping: index $old doesn't exist.\n" );
 
            return;
        }
 
        $this->db->query( "ALTER INDEX $old RENAME TO $new" );
    }
 
    protected function dropPgField( $table, $field ) {
        $fi = $this->db->fieldInfo( $table, $field );
        if ( is_null( $fi ) ) {
            $this->output( "...$table table does not contain $field field.\n" );
 
            return;
        } else {
            $this->output( "Dropping column '$table.$field'\n" );
            $this->db->query( "ALTER TABLE $table DROP COLUMN $field" );
        }
    }
 
    protected function addPgField( $table, $field, $type ) {
        $fi = $this->db->fieldInfo( $table, $field );
        if ( !is_null( $fi ) ) {
            $this->output( "...column '$table.$field' already exists\n" );
 
            return;
        } else {
            $this->output( "Adding column '$table.$field'\n" );
            $this->db->query( "ALTER TABLE $table ADD $field $type" );
        }
    }
 
    protected function changeField( $table, $field, $newtype, $default ) {
        $fi = $this->db->fieldInfo( $table, $field );
        if ( is_null( $fi ) ) {
            $this->output( "...ERROR: expected column $table.$field to exist\n" );
            exit( 1 );
        }
 
        if ( $fi->type() === $newtype ) {
            $this->output( "...column '$table.$field' is already of type '$newtype'\n" );
        } else {
            $this->output( "Changing column type of '$table.$field' from '{$fi->type()}' to '$newtype'\n" );
            $sql = "ALTER TABLE $table ALTER $field TYPE $newtype";
            if ( strlen( $default ) ) {
                $res = [];
                if ( preg_match( '/DEFAULT (.+)/', $default, $res ) ) {
                    $sqldef = "ALTER TABLE $table ALTER $field SET DEFAULT $res[1]";
                    $this->db->query( $sqldef );
                    $default = preg_replace( '/\s*DEFAULT .+/', '', $default );
                }
                $sql .= " USING $default";
            }
            $this->db->query( $sql );
        }
    }
 
    protected function changeFieldPurgeTable( $table, $field, $newtype, $default ) {
        # # For a cache table, empty it if the field needs to be changed, because the old contents
        # # may be corrupted.  If the column is already the desired type, refrain from purging.
        $fi = $this->db->fieldInfo( $table, $field );
        if ( is_null( $fi ) ) {
            $this->output( "...ERROR: expected column $table.$field to exist\n" );
            exit( 1 );
        }
 
        if ( $fi->type() === $newtype ) {
            $this->output( "...column '$table.$field' is already of type '$newtype'\n" );
        } else {
            $this->output( "Purging data from cache table '$table'\n" );
            $this->db->query( "DELETE from $table" );
            $this->output( "Changing column type of '$table.$field' from '{$fi->type()}' to '$newtype'\n" );
            $sql = "ALTER TABLE $table ALTER $field TYPE $newtype";
            if ( strlen( $default ) ) {
                $res = [];
                if ( preg_match( '/DEFAULT (.+)/', $default, $res ) ) {
                    $sqldef = "ALTER TABLE $table ALTER $field SET DEFAULT $res[1]";
                    $this->db->query( $sqldef );
                    $default = preg_replace( '/\s*DEFAULT .+/', '', $default );
                }
                $sql .= " USING $default";
            }
            $this->db->query( $sql );
        }
    }
 
    protected function setDefault( $table, $field, $default ) {
        $info = $this->db->fieldInfo( $table, $field );
        if ( $info->defaultValue() !== $default ) {
            $this->output( "Changing '$table.$field' default value\n" );
            $this->db->query( "ALTER TABLE $table ALTER $field SET DEFAULT "
                . $this->db->addQuotes( $default ) );
        }
    }
 
    protected function dropDefault( $table, $field ) {
        $info = $this->db->fieldInfo( $table, $field );
        if ( $info->defaultValue() !== false ) {
            $this->output( "Removing '$table.$field' default value\n" );
            $this->db->query( "ALTER TABLE $table ALTER $field DROP DEFAULT" );
        }
    }
 
    protected function changeNullableField( $table, $field, $null, $update = false ) {
        $fi = $this->db->fieldInfo( $table, $field );
        if ( is_null( $fi ) ) {
            return;
        }
        if ( $fi->isNullable() ) {
            # # It's NULL - does it need to be NOT NULL?
            if ( 'NOT NULL' === $null ) {
                $this->output( "Changing '$table.$field' to not allow NULLs\n" );
                if ( $update ) {
                    $this->db->query( "UPDATE $table SET $field = DEFAULT WHERE $field IS NULL" );
                }
                $this->db->query( "ALTER TABLE $table ALTER $field SET NOT NULL" );
            } else {
                $this->output( "...column '$table.$field' is already set as NULL\n" );
            }
        } else {
            # # It's NOT NULL - does it need to be NULL?
            if ( 'NULL' === $null ) {
                $this->output( "Changing '$table.$field' to allow NULLs\n" );
                $this->db->query( "ALTER TABLE $table ALTER $field DROP NOT NULL" );
            } else {
                $this->output( "...column '$table.$field' is already set as NOT NULL\n" );
            }
        }
    }
 
    public function addPgIndex( $table, $index, $type, $unique = false ) {
        if ( $this->db->indexExists( $table, $index ) ) {
            $this->output( "...index '$index' on table '$table' already exists\n" );
        } else {
            $this->output( "Creating index '$index' on table '$table' $type\n" );
            $unique = $unique ? 'UNIQUE' : '';
            $this->db->query( "CREATE $unique INDEX $index ON $table $type" );
        }
    }
 
    public function addPgExtIndex( $table, $index, $type ) {
        if ( $this->db->indexExists( $table, $index ) ) {
            $this->output( "...index '$index' on table '$table' already exists\n" );
        } else {
            if ( preg_match( '/^\‍(/', $type ) ) {
                $this->output( "Creating index '$index' on table '$table'\n" );
                $this->db->query( "CREATE INDEX $index ON $table $type" );
            } else {
                $this->applyPatch( $type, true, "Creating index '$index' on table '$table'" );
            }
        }
    }
 
    public function addPgEnumValue( $type, $value ) {
        $row = $this->db->selectRow(
            [
                't' => 'pg_catalog.pg_type',
                'n' => 'pg_catalog.pg_namespace',
                'e' => 'pg_catalog.pg_enum',
            ],
            [ 't.typname', 't.typtype', 'e.enumlabel' ],
            [
                't.typname' => $type,
                'n.nspname' => $this->db->getCoreSchema(),
            ],
            __METHOD__,
            [],
            [
                'n' => [ 'JOIN', 't.typnamespace = n.oid' ],
                'e' => [ 'LEFT JOIN', [ 'e.enumtypid = t.oid', 'e.enumlabel' => $value ] ],
            ]
        );
 
        if ( !$row ) {
            $this->output( "...Type $type does not exist, skipping modify enum.\n" );
        } elseif ( $row->typtype !== 'e' ) {
            $this->output( "...Type $type does not seem to be an enum, skipping modify enum.\n" );
        } elseif ( $row->enumlabel === $value ) {
            $this->output( "...Enum type $type already contains value '$value'.\n" );
        } else {
            $this->output( "...Adding value '$value' to enum type $type.\n" );
            $etype = $this->db->addIdentifierQuotes( $type );
            $evalue = $this->db->addQuotes( $value );
            $this->db->query( "ALTER TYPE $etype ADD VALUE $evalue" );
        }
    }
 
    protected function dropFkey( $table, $field ) {
        $fi = $this->db->fieldInfo( $table, $field );
        if ( is_null( $fi ) ) {
            $this->output( "WARNING! Column '$table.$field' does not exist but it should! " .
                "Please report this.\n" );
            return;
        }
        $conname = $fi->conname();
        if ( $fi->conname() ) {
            $this->output( "Dropping foreign key constraint on '$table.$field'\n" );
            $conclause = "CONSTRAINT \"$conname\"";
            $command = "ALTER TABLE $table DROP CONSTRAINT $conname";
            $this->db->query( $command );
        } else {
            $this->output( "...foreign key constraint on '$table.$field' already does not exist\n" );
        };
    }
 
    protected function changeFkeyDeferrable( $table, $field, $clause ) {
        $fi = $this->db->fieldInfo( $table, $field );
        if ( is_null( $fi ) ) {
            $this->output( "WARNING! Column '$table.$field' does not exist but it should! " .
                "Please report this.\n" );
 
            return;
        }
        if ( $fi->is_deferred() && $fi->is_deferrable() ) {
            return;
        }
        $this->output( "Altering column '$table.$field' to be DEFERRABLE INITIALLY DEFERRED\n" );
        $conname = $fi->conname();
        if ( $fi->conname() ) {
            $conclause = "CONSTRAINT \"$conname\"";
            $command = "ALTER TABLE $table DROP CONSTRAINT $conname";
            $this->db->query( $command );
        } else {
            $this->output( "Column '$table.$field' does not have a foreign key " .
                "constraint, will be added\n" );
            $conclause = "";
        }
        $command =
            "ALTER TABLE $table ADD $conclause " .
            "FOREIGN KEY ($field) REFERENCES $clause DEFERRABLE INITIALLY DEFERRED";
        $this->db->query( $command );
    }
 
    protected function convertArchive2() {
        if ( $this->db->tableExists( "archive2" ) ) {
            if ( $this->db->ruleExists( 'archive', 'archive_insert' ) ) {
                $this->output( "Dropping rule 'archive_insert'\n" );
                $this->db->query( 'DROP RULE archive_insert ON archive' );
            }
            if ( $this->db->ruleExists( 'archive', 'archive_delete' ) ) {
                $this->output( "Dropping rule 'archive_delete'\n" );
                $this->db->query( 'DROP RULE archive_delete ON archive' );
            }
            $this->applyPatch(
                'patch-remove-archive2.sql',
                false,
                "Converting 'archive2' back to normal archive table"
            );
        } else {
            $this->output( "...obsolete table 'archive2' does not exist\n" );
        }
    }
 
    protected function checkOiDeleted() {
        if ( $this->db->fieldInfo( 'oldimage', 'oi_deleted' )->type() !== 'smallint' ) {
            $this->output( "Changing 'oldimage.oi_deleted' to type 'smallint'\n" );
            $this->db->query( "ALTER TABLE oldimage ALTER oi_deleted DROP DEFAULT" );
            $this->db->query(
                "ALTER TABLE oldimage ALTER oi_deleted TYPE SMALLINT USING (oi_deleted::smallint)" );
            $this->db->query( "ALTER TABLE oldimage ALTER oi_deleted SET DEFAULT 0" );
        } else {
            $this->output( "...column 'oldimage.oi_deleted' is already of type 'smallint'\n" );
        }
    }
 
    protected function checkOiNameConstraint() {
        if ( $this->db->hasConstraint( "oldimage_oi_name_fkey_cascaded" ) ) {
            $this->output( "...table 'oldimage' has correct cascading delete/update " .
                "foreign key to image\n" );
        } else {
            if ( $this->db->hasConstraint( "oldimage_oi_name_fkey" ) ) {
                $this->db->query(
                    "ALTER TABLE oldimage DROP CONSTRAINT oldimage_oi_name_fkey" );
            }
            if ( $this->db->hasConstraint( "oldimage_oi_name_fkey_cascade" ) ) {
                $this->db->query(
                    "ALTER TABLE oldimage DROP CONSTRAINT oldimage_oi_name_fkey_cascade" );
            }
            $this->output( "Making foreign key on table 'oldimage' (to image) a cascade delete/update\n" );
            $this->db->query(
                "ALTER TABLE oldimage ADD CONSTRAINT oldimage_oi_name_fkey_cascaded " .
                "FOREIGN KEY (oi_name) REFERENCES image(img_name) " .
                "ON DELETE CASCADE ON UPDATE CASCADE" );
        }
    }
 
    protected function checkPageDeletedTrigger() {
        if ( !$this->db->triggerExists( 'page', 'page_deleted' ) ) {
            $this->applyPatch(
                'patch-page_deleted.sql',
                false,
                "Adding function and trigger 'page_deleted' to table 'page'"
            );
        } else {
            $this->output( "...table 'page' has 'page_deleted' trigger\n" );
        }
    }
 
    protected function dropPgIndex( $table, $index ) {
        if ( $this->db->indexExists( $table, $index ) ) {
            $this->output( "Dropping obsolete index '$index'\n" );
            $this->db->query( "DROP INDEX \"" . $index . "\"" );
        }
    }
 
    protected function checkIndex( $index, $should_be, $good_def ) {
        $pu = $this->db->indexAttributes( $index );
        if ( !empty( $pu ) && $pu != $should_be ) {
            $this->output( "Dropping obsolete version of index '$index'\n" );
            $this->db->query( "DROP INDEX \"" . $index . "\"" );
            $pu = [];
        } else {
            $this->output( "...no need to drop index '$index'\n" );
        }
 
        if ( empty( $pu ) ) {
            $this->output( "Creating index '$index'\n" );
            $this->db->query( $good_def );
        } else {
            $this->output( "...index '$index' exists\n" );
        }
    }
 
    protected function checkRevUserFkey() {
        if ( $this->fkeyDeltype( 'revision_rev_user_fkey' ) == 'r' ) {
            $this->output( "...constraint 'revision_rev_user_fkey' is ON DELETE RESTRICT\n" );
        } else {
            $this->applyPatch(
                'patch-revision_rev_user_fkey.sql',
                false,
                "Changing constraint 'revision_rev_user_fkey' to ON DELETE RESTRICT"
            );
        }
    }
 
    protected function checkIwlPrefix() {
        if ( $this->db->indexExists( 'iwlinks', 'iwl_prefix' ) ) {
            $this->applyPatch(
                'patch-rename-iwl_prefix.sql',
                false,
                "Replacing index 'iwl_prefix' with 'iwl_prefix_title_from'"
            );
        }
    }
 
    protected function addInterwikiType() {
        $this->applyPatch( 'patch-add_interwiki.sql', false, "Refreshing add_interwiki()" );
    }
 
    protected function tsearchFixes() {
        # Tweak the page_title tsearch2 trigger to filter out slashes
        # This is create or replace, so harmless to call if not needed
        $this->applyPatch( 'patch-ts2pagetitle.sql', false, "Refreshing ts2_page_title()" );
 
        # If the server is 8.3 or higher, rewrite the tsearch2 triggers
        # in case they have the old 'default' versions
        # Gather version numbers in case we need them
        if ( $this->db->getServerVersion() >= 8.3 ) {
            $this->applyPatch( 'patch-tsearch2funcs.sql', false, "Rewriting tsearch2 triggers" );
        }
    }
 
    protected function rebuildTextSearch() {
        if ( $this->updateRowExists( 'patch-textsearch_bug66650.sql' ) ) {
            $this->output( "...T68650 already fixed or not applicable.\n" );
            return;
        };
        $this->applyPatch( 'patch-textsearch_bug66650.sql', false,
            'Rebuilding text search for T68650' );
    }
}