From 314968036b431c01fe17db3da1c0555823f6898d Mon Sep 17 00:00:00 2001
From: Aaron Schulz <aschulz@wikimedia.org>
Date: Mon, 25 Mar 2019 23:54:39 -0700
Subject: [PATCH] rdbms: add ATTR_SCHEMAS_AS_TABLE_GROUPS attribute

Change-Id: Ia12a00c30039acd6c59726f35d03cc76aa957902
---
 includes/libs/rdbms/database/Database.php           | 13 +++++++++----
 includes/libs/rdbms/database/DatabaseMssql.php      |  3 +++
 includes/libs/rdbms/database/DatabasePostgres.php   |  4 ++++
 tests/phpunit/includes/db/DatabasePostgresTest.php  |  7 +++++++
 .../libs/rdbms/database/DatabaseMssqlTest.php       |  7 +++++++
 5 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/includes/libs/rdbms/database/Database.php b/includes/libs/rdbms/database/Database.php
index 9ce3086c38..e019bc848d 100644
--- a/includes/libs/rdbms/database/Database.php
+++ b/includes/libs/rdbms/database/Database.php
@@ -61,8 +61,10 @@ abstract class Database implements IDatabase, IMaintainableDatabase, LoggerAware
 	const SLOW_WRITE_SEC = 0.500;
 	const SMALL_WRITE_ROWS = 100;
 
-	/** @var string Whether lock granularity is on the level of the entire database */
+	/** @var string Lock granularity is on the level of the entire database */
 	const ATTR_DB_LEVEL_LOCKING = 'db-level-locking';
+	/** @var string The SCHEMA keyword refers to a grouping of tables in a database */
+	const ATTR_SCHEMAS_AS_TABLE_GROUPS = 'supports-schemas';
 
 	/** @var int New Database instance will not be connected yet when returned */
 	const NEW_UNCONNECTED = 0;
@@ -475,12 +477,15 @@ abstract class Database implements IDatabase, IMaintainableDatabase, LoggerAware
 	/**
 	 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
 	 * @param string|null $driver Optional name of a specific DB client driver
-	 * @return array Map of (Database::ATTRIBUTE_* constant => value) for all such constants
+	 * @return array Map of (Database::ATTR_* constant => value) for all such constants
 	 * @throws InvalidArgumentException
 	 * @since 1.31
 	 */
 	final public static function attributesFromType( $dbType, $driver = null ) {
-		static $defaults = [ self::ATTR_DB_LEVEL_LOCKING => false ];
+		static $defaults = [
+			self::ATTR_DB_LEVEL_LOCKING => false,
+			self::ATTR_SCHEMAS_AS_TABLE_GROUPS => false
+		];
 
 		$class = self::getClass( $dbType, $driver );
 
@@ -544,7 +549,7 @@ abstract class Database implements IDatabase, IMaintainableDatabase, LoggerAware
 	}
 
 	/**
-	 * @return array Map of (Database::ATTRIBUTE_* constant => value
+	 * @return array Map of (Database::ATTR_* constant => value
 	 * @since 1.31
 	 */
 	protected static function getAttributes() {
diff --git a/includes/libs/rdbms/database/DatabaseMssql.php b/includes/libs/rdbms/database/DatabaseMssql.php
index ad5cf98f5c..866f5811f4 100644
--- a/includes/libs/rdbms/database/DatabaseMssql.php
+++ b/includes/libs/rdbms/database/DatabaseMssql.php
@@ -1412,6 +1412,9 @@ class DatabaseMssql extends Database {
 		return "CAST( $field AS NVARCHAR )";
 	}
 
+	public static function getAttributes() {
+		return [ self::ATTR_SCHEMAS_AS_TABLE_GROUPS => true ];
+	}
 }
 
 /**
diff --git a/includes/libs/rdbms/database/DatabasePostgres.php b/includes/libs/rdbms/database/DatabasePostgres.php
index 481dd9a6be..86be8f4141 100644
--- a/includes/libs/rdbms/database/DatabasePostgres.php
+++ b/includes/libs/rdbms/database/DatabasePostgres.php
@@ -1458,6 +1458,10 @@ SQL;
 		return $row ? ( strtolower( $row->default_transaction_read_only ) === 'on' ) : false;
 	}
 
+	public static function getAttributes() {
+		return [ self::ATTR_SCHEMAS_AS_TABLE_GROUPS => true ];
+	}
+
 	/**
 	 * @param string $lockName
 	 * @return string Integer
diff --git a/tests/phpunit/includes/db/DatabasePostgresTest.php b/tests/phpunit/includes/db/DatabasePostgresTest.php
index 6b1ed7fa21..e0b81117f9 100644
--- a/tests/phpunit/includes/db/DatabasePostgresTest.php
+++ b/tests/phpunit/includes/db/DatabasePostgresTest.php
@@ -1,5 +1,6 @@
 <?php
 
+use Wikimedia\Rdbms\Database;
 use Wikimedia\Rdbms\IDatabase;
 use Wikimedia\Rdbms\DatabasePostgres;
 use Wikimedia\ScopedCallback;
@@ -179,4 +180,10 @@ class DatabasePostgresTest extends MediaWikiTestCase {
 		$this->doTestInsertSelectIgnore();
 	}
 
+	/**
+	 * @covers \Wikimedia\Rdbms\DatabasePostgres::getAttributes
+	 */
+	public function testAttributes() {
+		$this->assertTrue( DatabasePostgres::getAttributes()[Database::ATTR_SCHEMAS_AS_TABLE_GROUPS] );
+	}
 }
diff --git a/tests/phpunit/includes/libs/rdbms/database/DatabaseMssqlTest.php b/tests/phpunit/includes/libs/rdbms/database/DatabaseMssqlTest.php
index b28a5b9eec..414042ddcf 100644
--- a/tests/phpunit/includes/libs/rdbms/database/DatabaseMssqlTest.php
+++ b/tests/phpunit/includes/libs/rdbms/database/DatabaseMssqlTest.php
@@ -1,5 +1,6 @@
 <?php
 
+use Wikimedia\Rdbms\Database;
 use Wikimedia\Rdbms\DatabaseMssql;
 
 class DatabaseMssqlTest extends PHPUnit\Framework\TestCase {
@@ -52,4 +53,10 @@ class DatabaseMssqlTest extends PHPUnit\Framework\TestCase {
 		$mockDb->buildSubstring( 'foo', $start, $length );
 	}
 
+	/**
+	 * @covers \Wikimedia\Rdbms\DatabaseMssql::getAttributes
+	 */
+	public function testAttributes() {
+		$this->assertTrue( DatabaseMssql::getAttributes()[Database::ATTR_SCHEMAS_AS_TABLE_GROUPS] );
+	}
 }
-- 
2.20.1