CX: Add new index to speed up query in "findByPublishedTitle" method

This patch adds a new index on the translation target title column of
the "cx_translations" table, to speed up the query by reducing a full
table scan, to scanning a few rows that match the given published
title.

Bug: T351999
Change-Id: Ib0b800966c47287e4e4d19ede043596ade26b4f8

includes/SchemaHooks.php

@@ -20,7 +20,7 @@ public function onLoadExtensionSchemaUpdates( $updater ) {
 		global $wgContentTranslationCluster, $wgContentTranslationDatabase;
 
 		// Following tables should only be created if both cluster and database are false.
-		// Otherwise they are not created in the place they are accesses, because
+		// Otherwise, they are not created in the place they are accesses, because
 		// DatabaseUpdater does not support other databases other than main wiki schema.
 		if ( $wgContentTranslationCluster !== false || $wgContentTranslationDatabase !== false ) {
 			return;
@@ -89,6 +89,11 @@ public function onLoadExtensionSchemaUpdates( $updater ) {
 			'cx_translation_translators',
 			"$dir/sql/$dbType/patch-cx_translators-unique-to-pk.sql"
 		);
+		$updater->addExtensionIndex(
+			'cx_translations',
+			'cx_translation_target_title',
+			"$dir/sql/$dbType/patch-cx_translations-target-title-index.sql"
+		);
 	}
 
 }

includes/Store/TranslationStore.php

@@ -138,7 +138,6 @@ public function findByPublishedTitle( string $publishedTitle, string $targetLang
 			LIST_OR
 		);
 
-		// TODO: Add index to improve performance for this read query
 		$row = $dbr->newSelectQueryBuilder()
 			->select( ISQLPlatform::ALL_ROWS )
 			->from( self::TRANSLATION_TABLE_NAME )

sql/abstractSchemaChanges/patch-cx_translations-target-title-index.json

@@ -0,0 +1,246 @@
+{
+	"comment": "Add index to make finding of published translation by title faster (T351999)",
+	"before": {
+		"name": "cx_translations",
+		"columns": [
+			{
+				"name": "translation_id",
+				"comment": "translation id. Autogenerated.",
+				"type": "integer",
+				"options": { "autoincrement": true, "notnull": true }
+			},
+			{
+				"name": "translation_source_title",
+				"comment": "Source title of the translation",
+				"type": "binary",
+				"options": { "notnull": true, "length": 512 }
+			},
+			{
+				"name": "translation_target_title",
+				"comment": "Target title of the translation",
+				"type": "binary",
+				"options": { "notnull": true, "length": 512 }
+			},
+			{
+				"name": "translation_source_language",
+				"comment": "Source language. language code",
+				"type": "binary",
+				"options": { "notnull": true, "length": 36 }
+			},
+			{
+				"name": "translation_target_language",
+				"comment": "Target language. language code",
+				"type": "binary",
+				"options": { "notnull": true, "length": 36 }
+			},
+			{
+				"name": "translation_source_revision_id",
+				"comment": "Revision id of source article",
+				"type": "integer",
+				"options": { "notnull": false, "unsigned": true }
+			},
+			{
+				"name": "translation_target_revision_id",
+				"comment": "Revision id of published translation",
+				"type": "integer",
+				"options": { "notnull": false, "unsigned": true }
+			},
+			{
+				"name": "translation_source_url",
+				"comment": "source of the page as full canonical url -- https://www.mediawiki.org/wiki/Help:CxIsPage",
+				"type": "blob",
+				"options": { "notnull": true, "length": 65535 }
+			},
+			{
+				"name": "translation_target_url",
+				"comment": "link to the draft/published target",
+				"type": "blob",
+				"options": { "notnull": false, "length": 65535 }
+			},
+			{
+				"name": "translation_status",
+				"comment": "Status of translation - Draft or published status. There is no final status. A published translation can be draft again to update again",
+				"type": "mwenum",
+				"options": {
+					"notnull": false,
+					"CustomSchemaOptions": {
+						"enum_values": [ "draft", "published", "deleted" ]
+					}
+				}
+			},
+			{
+				"name": "translation_start_timestamp",
+				"comment": "Start date of this translation",
+				"type": "mwtimestamp",
+				"options": { "notnull": true }
+			},
+			{
+				"name": "translation_last_updated_timestamp",
+				"comment": "Last updated date of this translation",
+				"type": "mwtimestamp",
+				"options": { "notnull": true }
+			},
+			{
+				"name": "translation_progress",
+				"comment": "Progress of the translation - json dump",
+				"type": "blob",
+				"options": { "notnull": true, "length": 255 }
+			},
+			{
+				"name": "translation_started_by",
+				"comment": "Who started this translation? User id",
+				"type": "integer",
+				"options": { "notnull": false }
+			},
+			{
+				"name": "translation_last_update_by",
+				"comment": "Who did the last translation? It need not be the translator who started.",
+				"type": "integer",
+				"options": { "notnull": false }
+			},
+			{
+				"name": "translation_cx_version",
+				"comment": "Field to indicate which version of CX",
+				"type": "mwtinyint",
+				"options": { "notnull": false, "unsigned": true, "default": 1 }
+			}
+		],
+		"indexes": [
+			{
+				"name": "cx_translation_ref",
+				"columns": [ "translation_source_title", "translation_source_language", "translation_target_language", "translation_started_by" ],
+				"unique": true
+			},
+			{
+				"name": "cx_translation_languages",
+				"columns": [ "translation_source_language", "translation_target_language", "translation_status" ],
+				"unique": false
+			}
+		],
+		"pk": [ "translation_id" ]
+	},
+	"after": {
+		"name": "cx_translations",
+		"columns": [
+			{
+				"name": "translation_id",
+				"comment": "translation id. Autogenerated.",
+				"type": "integer",
+				"options": { "autoincrement": true, "notnull": true }
+			},
+			{
+				"name": "translation_source_title",
+				"comment": "Source title of the translation",
+				"type": "binary",
+				"options": { "notnull": true, "length": 512 }
+			},
+			{
+				"name": "translation_target_title",
+				"comment": "Target title of the translation",
+				"type": "binary",
+				"options": { "notnull": true, "length": 512 }
+			},
+			{
+				"name": "translation_source_language",
+				"comment": "Source language. language code",
+				"type": "binary",
+				"options": { "notnull": true, "length": 36 }
+			},
+			{
+				"name": "translation_target_language",
+				"comment": "Target language. language code",
+				"type": "binary",
+				"options": { "notnull": true, "length": 36 }
+			},
+			{
+				"name": "translation_source_revision_id",
+				"comment": "Revision id of source article",
+				"type": "integer",
+				"options": { "notnull": false, "unsigned": true }
+			},
+			{
+				"name": "translation_target_revision_id",
+				"comment": "Revision id of published translation",
+				"type": "integer",
+				"options": { "notnull": false, "unsigned": true }
+			},
+			{
+				"name": "translation_source_url",
+				"comment": "source of the page as full canonical url -- https://www.mediawiki.org/wiki/Help:CxIsPage",
+				"type": "blob",
+				"options": { "notnull": true, "length": 65535 }
+			},
+			{
+				"name": "translation_target_url",
+				"comment": "link to the draft/published target",
+				"type": "blob",
+				"options": { "notnull": false, "length": 65535 }
+			},
+			{
+				"name": "translation_status",
+				"comment": "Status of translation - Draft or published status. There is no final status. A published translation can be draft again to update again",
+				"type": "mwenum",
+				"options": {
+					"notnull": false,
+					"CustomSchemaOptions": {
+						"enum_values": [ "draft", "published", "deleted" ]
+					}
+				}
+			},
+			{
+				"name": "translation_start_timestamp",
+				"comment": "Start date of this translation",
+				"type": "mwtimestamp",
+				"options": { "notnull": true }
+			},
+			{
+				"name": "translation_last_updated_timestamp",
+				"comment": "Last updated date of this translation",
+				"type": "mwtimestamp",
+				"options": { "notnull": true }
+			},
+			{
+				"name": "translation_progress",
+				"comment": "Progress of the translation - json dump",
+				"type": "blob",
+				"options": { "notnull": true, "length": 255 }
+			},
+			{
+				"name": "translation_started_by",
+				"comment": "Who started this translation? User id",
+				"type": "integer",
+				"options": { "notnull": false }
+			},
+			{
+				"name": "translation_last_update_by",
+				"comment": "Who did the last translation? It need not be the translator who started.",
+				"type": "integer",
+				"options": { "notnull": false }
+			},
+			{
+				"name": "translation_cx_version",
+				"comment": "Field to indicate which version of CX",
+				"type": "mwtinyint",
+				"options": { "notnull": false, "unsigned": true, "default": 1 }
+			}
+		],
+		"indexes": [
+			{
+				"name": "cx_translation_ref",
+				"columns": [ "translation_source_title", "translation_source_language", "translation_target_language", "translation_started_by" ],
+				"unique": true
+			},
+			{
+				"name": "cx_translation_languages",
+				"columns": [ "translation_source_language", "translation_target_language", "translation_status" ],
+				"unique": false
+			},
+			{
+				"name": "cx_translation_target_title",
+				"columns": [ "translation_target_title" ],
+				"unique": false
+			}
+		],
+		"pk": [ "translation_id" ]
+	}
+}

sql/mysql/patch-cx_translations-target-title-index.sql

@@ -0,0 +1,5 @@
+-- This file is automatically generated using maintenance/generateSchemaChangeSql.php.
+-- Source: extensions/ContentTranslation/sql/abstractSchemaChanges/patch-cx_translations-target-title-index.json
+-- Do not modify this file directly.
+-- See https://www.mediawiki.org/wiki/Manual:Schema_changes
+CREATE INDEX cx_translation_target_title ON /*_*/cx_translations (translation_target_title);

sql/mysql/tables-generated.sql

@@ -27,6 +27,7 @@ CREATE TABLE /*_*/cx_translations (
     translation_source_language, translation_target_language,
     translation_status
   ),
+  INDEX cx_translation_target_title (translation_target_title),
   PRIMARY KEY(translation_id)
 ) /*$wgDBTableOptions*/;
 

sql/postgres/patch-cx_translations-target-title-index.sql

@@ -0,0 +1,5 @@
+-- This file is automatically generated using maintenance/generateSchemaChangeSql.php.
+-- Source: extensions/ContentTranslation/sql/abstractSchemaChanges/patch-cx_translations-target-title-index.json
+-- Do not modify this file directly.
+-- See https://www.mediawiki.org/wiki/Manual:Schema_changes
+CREATE INDEX cx_translation_target_title ON cx_translations (translation_target_title);

sql/postgres/tables-generated.sql

@@ -32,6 +32,8 @@ CREATE INDEX cx_translation_languages ON cx_translations (
   translation_status
 );
 
+CREATE INDEX cx_translation_target_title ON cx_translations (translation_target_title);
+
 
 CREATE TABLE cx_translators (
   translator_user_id INT NOT NULL,

sql/sqlite/patch-cx_translations-target-title-index.sql

@@ -0,0 +1,87 @@
+-- This file is automatically generated using maintenance/generateSchemaChangeSql.php.
+-- Source: extensions/ContentTranslation/sql/abstractSchemaChanges/patch-cx_translations-target-title-index.json
+-- Do not modify this file directly.
+-- See https://www.mediawiki.org/wiki/Manual:Schema_changes
+CREATE TEMPORARY TABLE /*_*/__temp__cx_translations AS
+SELECT
+  translation_id,
+  translation_source_title,
+  translation_target_title,
+  translation_source_language,
+  translation_target_language,
+  translation_source_revision_id,
+  translation_target_revision_id,
+  translation_source_url,
+  translation_target_url,
+  translation_status,
+  translation_start_timestamp,
+  translation_last_updated_timestamp,
+  translation_progress,
+  translation_started_by,
+  translation_last_update_by,
+  translation_cx_version
+FROM /*_*/cx_translations;
+DROP TABLE /*_*/cx_translations;
+
+
+CREATE TABLE /*_*/cx_translations (
+    translation_id INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL,
+    translation_source_title BLOB NOT NULL,
+    translation_target_title BLOB NOT NULL,
+    translation_source_language BLOB NOT NULL,
+    translation_target_language BLOB NOT NULL,
+    translation_source_revision_id INTEGER UNSIGNED DEFAULT NULL,
+    translation_target_revision_id INTEGER UNSIGNED DEFAULT NULL,
+    translation_source_url BLOB NOT NULL,
+    translation_target_url BLOB DEFAULT NULL,
+    translation_status TEXT DEFAULT NULL,
+    translation_start_timestamp BLOB NOT NULL,
+    translation_last_updated_timestamp BLOB NOT NULL,
+    translation_progress BLOB NOT NULL,
+    translation_started_by INTEGER DEFAULT NULL,
+    translation_last_update_by INTEGER DEFAULT NULL,
+    translation_cx_version SMALLINT UNSIGNED DEFAULT 1
+  );
+INSERT INTO /*_*/cx_translations (
+    translation_id, translation_source_title,
+    translation_target_title, translation_source_language,
+    translation_target_language, translation_source_revision_id,
+    translation_target_revision_id,
+    translation_source_url, translation_target_url,
+    translation_status, translation_start_timestamp,
+    translation_last_updated_timestamp,
+    translation_progress, translation_started_by,
+    translation_last_update_by, translation_cx_version
+  )
+SELECT
+  translation_id,
+  translation_source_title,
+  translation_target_title,
+  translation_source_language,
+  translation_target_language,
+  translation_source_revision_id,
+  translation_target_revision_id,
+  translation_source_url,
+  translation_target_url,
+  translation_status,
+  translation_start_timestamp,
+  translation_last_updated_timestamp,
+  translation_progress,
+  translation_started_by,
+  translation_last_update_by,
+  translation_cx_version
+FROM
+  /*_*/__temp__cx_translations;
+DROP TABLE /*_*/__temp__cx_translations;
+
+CREATE UNIQUE INDEX cx_translation_ref ON /*_*/cx_translations (
+    translation_source_title, translation_source_language,
+    translation_target_language, translation_started_by
+  );
+
+CREATE INDEX cx_translation_languages ON /*_*/cx_translations (
+    translation_source_language, translation_target_language,
+    translation_status
+  );
+
+CREATE INDEX cx_translation_target_title ON /*_*/cx_translations (translation_target_title);