From: Bart Visscher <bartv@thisnet.nl>
Date: Mon, 25 Feb 2013 20:46:03 +0000 (+0100)
Subject: Move limit/offset handling to Connection wrapper
X-Git-Tag: v6.0.0alpha2~337^2~19
X-Git-Url: https://source.dussan.org/?a=commitdiff_plain;h=1d5d23a1de5a490595d8bb7ea81b8bda48b8feeb;p=nextcloud-server.git

Move limit/offset handling to Connection wrapper
---

diff --git a/lib/db.php b/lib/db.php
index c5690bdd8a9..4451f813905 100644
--- a/lib/db.php
+++ b/lib/db.php
@@ -213,16 +213,6 @@ class OC_DB {
 	 * SQL query via Doctrine prepare(), needs to be execute()'d!
 	 */
 	static public function prepare( $query , $limit = null, $offset = null, $isManipulation = null) {
-
-		if (!is_null($limit) && $limit != -1) {
-			if ($limit === -1) {
-				$limit = null;
-			}
-			$platform = self::$connection->getDatabasePlatform();
-			$query = $platform->modifyLimitQuery($query, $limit, $offset);
-			}
-		}
-
 		// Optimize the query
 		$query = self::processQuery( $query );
 		if(OC_Config::getValue( "log_query", false)) {
@@ -238,7 +228,7 @@ class OC_DB {
 		// return the result
 		if (self::$backend == self::BACKEND_DOCTRINE) {
 			try {
-				$result=self::$connection->prepare($query);
+				$result=self::$connection->prepare($query, $limit, $offset);
 			} catch(\Doctrine\DBAL\DBALException $e) {
 				throw new \DatabaseException($e->getMessage(), $query);
 			}
@@ -493,64 +483,11 @@ class OC_DB {
 			$query = str_replace( 'LENGTH(', 'LEN(', $query );
 			$query = str_replace( 'SUBSTR(', 'SUBSTRING(', $query );
 			$query = str_ireplace( 'UNIX_TIMESTAMP()', 'DATEDIFF(second,{d \'1970-01-01\'},GETDATE())', $query );
-
-			$query = self::fixLimitClauseForMSSQL($query);
 		}
 
 		return $query;
 	}
 
-	private static function fixLimitClauseForMSSQL($query) {
-		$limitLocation = stripos ($query, "LIMIT");
-
-		if ( $limitLocation === false ) {
-			return $query;
-		} 
-
-		// total == 0 means all results - not zero results
-		//
-		// First number is either total or offset, locate it by first space
-		//
-		$offset = substr ($query, $limitLocation + 5);
-		$offset = substr ($offset, 0, stripos ($offset, ' '));
-		$offset = trim ($offset);
-
-		// check for another parameter
-		if (stripos ($offset, ',') === false) {
-			// no more parameters
-			$offset = 0;
-			$total = intval ($offset);
-		} else {
-			// found another parameter
-			$offset = intval ($offset);
-
-			$total = substr ($query, $limitLocation + 5);
-			$total = substr ($total, stripos ($total, ','));
-
-			$total = substr ($total, 0, stripos ($total, ' '));
-			$total = intval ($total);
-		}
-
-		$query = trim (substr ($query, 0, $limitLocation));
-
-		if ($offset == 0 && $total !== 0) {
-			if (strpos($query, "SELECT") === false) {
-				$query = "TOP {$total} " . $query;
-			} else {
-				$query = preg_replace('/SELECT(\s*DISTINCT)?/Dsi', 'SELECT$1 TOP '.$total, $query);
-			}
-		} else if ($offset > 0) {
-			$query = preg_replace('/SELECT(\s*DISTINCT)?/Dsi', 'SELECT$1 TOP(10000000) ', $query);
-			$query = 'SELECT *
-					FROM (SELECT sub2.*, ROW_NUMBER() OVER(ORDER BY sub2.line2) AS line3
-					FROM (SELECT 1 AS line2, sub1.* FROM (' . $query . ') AS sub1) as sub2) AS sub3';
-
-			if ($total > 0) {
-				$query .= ' WHERE line3 BETWEEN ' . ($offset + 1) . ' AND ' . ($offset + $total);
-			} else {
-				$query .= ' WHERE line3 > ' . $offset;
-			}
-		}
 		return $query;
 	}
 
diff --git a/lib/db/connection.php b/lib/db/connection.php
index 763251c1903..c8695b13190 100644
--- a/lib/db/connection.php
+++ b/lib/db/connection.php
@@ -50,8 +50,12 @@ class Connection extends \Doctrine\DBAL\Connection {
 	 */
 	public function prepare( $statement, $limit=null, $offset=null ) {
 		$statement = $this->replaceTablePrefix($statement);
-		if (!is_null($limit) && $limit != -1) {
-			// TODO: limit & offset
+		if ($limit === -1) {
+			$limit = null;
+		}
+		if (!is_null($limit)) {
+			$platform = $this->getDatabasePlatform();
+			$statement = $platform->modifyLimitQuery($statement, $limit, $offset);
 		} else {
 			if (isset($this->preparedQueries[$statement]) && $this->cachingQueryStatementEnabled) {
 				return $this->preparedQueries[$statement];
@@ -59,7 +63,7 @@ class Connection extends \Doctrine\DBAL\Connection {
 		}
 		$rawQuery = $statement;
 		$result = parent::prepare($statement);
-		if ((is_null($limit) || $limit == -1) && $this->cachingQueryStatementEnabled) {
+		if (is_null($limit) && $this->cachingQueryStatementEnabled) {
 			$this->preparedQueries[$rawQuery] = $result;
 		}
 		return $result;