Merge "Make addIdentifierQuotes part of IDatabase"

[lhc/web/wiklou.git] / includes / libs / rdbms / database / Database.php

diff --git a/includes/libs/rdbms/database/Database.php b/includes/libs/rdbms/database/Database.php
index 174182f..49b2792 100644 (file)
--- a/includes/libs/rdbms/database/Database.php
+++ b/includes/libs/rdbms/database/Database.php
@@ -1019,13 +1019,22 @@ abstract class Database implements IDatabase, IMaintainableDatabase, LoggerAware
        }
 
        /**
-        * Run a query and return a DBMS-dependent wrapper (that has all IResultWrapper methods)
+        * Run a query and return a DBMS-dependent wrapper or boolean
         *
-        * This might return things, such as mysqli_result, that do not formally implement
-        * IResultWrapper, but nonetheless implement all of its methods correctly
+        * For SELECT queries, this returns either:
+        *   - a) A driver-specific value/resource, only on success. This can be iterated
+        *        over by calling fetchObject()/fetchRow() until there are no more rows.
+        *        Alternatively, the result can be passed to resultObject() to obtain a
+        *        ResultWrapper instance which can then be iterated over via "foreach".
+        *   - b) False, on any query failure
         *
-        * @param string $sql SQL query.
-        * @return IResultWrapper|bool Iterator to feed to fetchObject/fetchRow; false on failure
+        * For non-SELECT queries, this returns either:
+        *   - a) A driver-specific value/resource, only on success
+        *   - b) True, only on success (e.g. no meaningful result other than "OK")
+        *   - c) False, on any query failure
+        *
+        * @param string $sql SQL query
+        * @return mixed|bool An object, resource, or true on success; false on failure
         */
        abstract protected function doQuery( $sql );
 
@@ -1338,12 +1347,19 @@ abstract class Database implements IDatabase, IMaintainableDatabase, LoggerAware
        }
 
        /**
+        * Error out if the DB is not in a valid state for a query via query()
+        *
         * @param string $sql
         * @param string $fname
         * @throws DBTransactionStateError
         */
        private function assertTransactionStatus( $sql, $fname ) {
-               if ( $this->getQueryVerb( $sql ) === 'ROLLBACK' ) { // transaction/savepoint
+               $verb = $this->getQueryVerb( $sql );
+               if ( $verb === 'USE' ) {
+                       throw new DBUnexpectedError( $this, "Got USE query; use selectDomain() instead." );
+               }
+
+               if ( $verb === 'ROLLBACK' ) { // transaction/savepoint
                        return;
                }
 
@@ -2278,7 +2294,9 @@ abstract class Database implements IDatabase, IMaintainableDatabase, LoggerAware
        }
 
        public function buildStringCast( $field ) {
-               return $field;
+               // In theory this should work for any standards-compliant
+               // SQL implementation, although it may not be the best way to do it.
+               return "CAST( $field AS CHARACTER )";
        }
 
        public function buildIntegerCast( $field ) {