Add MS SQL TOP style syntax support

Quipulabz · Aug 28, 2013 · baff6ed · baff6ed
2 parents 4e9f892 + 33c3937
commit baff6ed
Show file tree

Hide file tree

Showing 11 changed files with 150 additions and 28 deletions.
diff --git a/README.markdown b/README.markdown
@@ -72,11 +72,13 @@ Changelog
 * Add PSR-1 compliant camelCase method calls to Idiorm (PHP 5.3+ required) [[crhayes](https://github.com/crhayes)] - [issue #108](https://github.com/j4mie/idiorm/issues/108)
 * Add static method `get_config()` to access current configuration [[javierd](https://github.com/mikejestes)] - [issue #141](https://github.com/j4mie/idiorm/issues/141)
 * Add logging callback functionality [[lalop](https://github.com/lalop)] - [issue #130](https://github.com/j4mie/idiorm/issues/130)
+* Add support for MS SQL ``TOP`` limit style (automatically used for PDO drivers: sqlsrv, dblib and mssql) [[numkem](https://github.com/numkem)] - [issue #116](https://github.com/j4mie/idiorm/issues/116)
 * Uses table aliases in `WHERE` clauses [[vicvicvic](https://github.com/vicvicvic)] - [issue #140](https://github.com/j4mie/idiorm/issues/140)
 * Ignore result columns when calling an aggregate function [[tassoevan](https://github.com/tassoevan)] - [issue #120](https://github.com/j4mie/idiorm/issues/120)
 * Improve documentation [[bruston](https://github.com/bruston)] - [issue #111](https://github.com/j4mie/idiorm/issues/111)
 * Improve PHPDoc on `get_db()` [[mailopl](https://github.com/mailopl)] - [issue #106](https://github.com/j4mie/idiorm/issues/106)
 * Improve documentation [[sjparsons](https://github.com/sjparsons)] - [issue #103](https://github.com/j4mie/idiorm/issues/103)
+* Make tests/bootstrap.php [[JoelMarcey](https://github.com/JoelMarcey)] - [issue #143](https://github.com/j4mie/idiorm/issues/143)
 
 #### 1.3.0 - release 2013-01-31
 

diff --git a/docs/configuration.rst b/docs/configuration.rst
@@ -212,6 +212,22 @@ the table, you can use the following configuration:
         'role' => 'role_id',
     ));
 
+Limit clause style
+^^^^^^^^^^^^^^^^^^
+
+Setting: ``limit_clause_style``
+
+You can specify the limit clause style in the configuration. This is to facilitate
+a MS SQL style limit clause that uses the ``TOP`` syntax.
+
+Acceptable values are ``ORM::LIMIT_STYLE_TOP_N`` and ``ORM::LIMIT_STYLE_LIMIT``.
+
+.. note::
+
+    If the PDO driver you are using is one of sqlsrv, dblib or mssql then Idiorm
+    will automatically select the ``ORM::LIMIT_STYLE_TOP_N`` for you unless you
+    override the setting.
+
 Query logging
 ^^^^^^^^^^^^^
 

diff --git a/idiorm.php b/idiorm.php
@@ -50,6 +50,10 @@ class ORM implements ArrayAccess {
 
         const DEFAULT_CONNECTION = 'default';
 
+        // Limit clause style
+        const LIMIT_STYLE_TOP_N = "top";
+        const LIMIT_STYLE_LIMIT = "limit";
+
         // ------------------------ //
         // --- CLASS PROPERTIES --- //
         // ------------------------ //
@@ -64,6 +68,7 @@ class ORM implements ArrayAccess {
             'password' => null,
             'driver_options' => null,
             'identifier_quote_character' => null, // if this is null, will be autodetected
+            'limit_clause_style' => null, // if this is null, will be autodetected
             'logging' => false,
             'logger' => null,
             'caching' => false,
@@ -210,6 +215,13 @@ public static function get_config($key = null, $connection_name = self::DEFAULT_
             }
         }
 
+        /**
+         * Delete all configs in _config array.
+         */
+        public static function reset_config() {
+            self::$_config = array();
+        }
+
         /**
          * Despite its slightly odd name, this is actually the factory
          * method used to acquire instances of the class. It is named
@@ -268,6 +280,14 @@ public static function set_db($db, $connection_name = self::DEFAULT_CONNECTION)
             self::_setup_db_config($connection_name);
             self::$_db[$connection_name] = $db;
             self::_setup_identifier_quote_character($connection_name);
+            self::_setup_limit_clause_style($connection_name);
+        }
+
+        /**
+         * Delete all registered PDO objects in _db array.
+         */
+        public static function reset_db() {
+            self::$_db = array();
         }
 
         /**
@@ -280,7 +300,20 @@ public static function set_db($db, $connection_name = self::DEFAULT_CONNECTION)
         protected static function _setup_identifier_quote_character($connection_name) {
             if (is_null(self::$_config[$connection_name]['identifier_quote_character'])) {
                 self::$_config[$connection_name]['identifier_quote_character'] =
-                     self::_detect_identifier_quote_character($connection_name);
+                    self::_detect_identifier_quote_character($connection_name);
+            }
+        }
+
+        /**
+         * Detect and initialise the limit clause style ("SELECT TOP 5" /
+         * "... LIMIT 5"). If this has been specified manually using 
+         * ORM::configure('limit_clause_style', 'top'), this will do nothing.
+         * @param string $connection_name Which connection to use
+         */
+        public static function _setup_limit_clause_style($connection_name) {
+            if (is_null(self::$_config[$connection_name]['limit_clause_style'])) {
+                self::$_config[$connection_name]['limit_clause_style'] =
+                    self::_detect_limit_clause_style($connection_name);
             }
         }
 
@@ -307,6 +340,23 @@ protected static function _detect_identifier_quote_character($connection_name) {
             }
         }
 
+        /**
+         * Returns a constant after determining the appropriate limit clause
+         * style
+         * @param string $connection_name Which connection to use
+         * @return string Limit clause style keyword/constant
+         */
+        protected static function _detect_limit_clause_style($connection_name) {
+            switch(self::$_db[$connection_name]->getAttribute(PDO::ATTR_DRIVER_NAME)) {
+                case 'sqlsrv':
+                case 'dblib':
+                case 'mssql':
+                    return ORM::LIMIT_STYLE_TOP_N;
+                default:
+                    return ORM::LIMIT_STYLE_LIMIT;
+            }
+        }
+
         /**
          * Returns the PDO instance used by the the ORM to communicate with
          * the database. This can be called if any low-level DB access is
@@ -1318,13 +1368,19 @@ protected function _build_select() {
          * Build the start of the SELECT statement
          */
         protected function _build_select_start() {
+            $fragment = 'SELECT ';
             $result_columns = join(', ', $this->_result_columns);
 
+            if (!is_null($this->_limit) &&
+                self::$_config[$this->_connection_name]['limit_clause_style'] === ORM::LIMIT_STYLE_TOP_N) {
+                $fragment .= "TOP {$this->_limit} ";
+            }
+
             if ($this->_distinct) {
                 $result_columns = 'DISTINCT ' . $result_columns;
             }
 
-            $fragment = "SELECT {$result_columns} FROM " . $this->_quote_identifier($this->_table_name);
+            $fragment .= "{$result_columns} FROM " . $this->_quote_identifier($this->_table_name);
 
             if (!is_null($this->_table_alias)) {
                 $fragment .= " " . $this->_quote_identifier($this->_table_alias);
@@ -1402,14 +1458,17 @@ protected function _build_order_by() {
          * Build LIMIT
          */
         protected function _build_limit() {
-            if (!is_null($this->_limit)) {
-                $clause = 'LIMIT';
+            $fragment = '';
+            if (!is_null($this->_limit) &&
+                self::$_config[$this->_connection_name]['limit_clause_style'] == ORM::LIMIT_STYLE_LIMIT) {
                 if (self::$_db[$this->_connection_name]->getAttribute(PDO::ATTR_DRIVER_NAME) == 'firebird') {
-                    $clause = 'ROWS';
+                    $fragment = 'ROWS';
+                } else {
+                    $fragment = 'LIMIT';
                 }
-                return "$clause " . $this->_limit;
+                $fragment .= " {$this->_limit}";
             }
-            return '';
+            return $fragment;
         }
 
         /**

diff --git a/test/CacheTest.php b/test/CacheTest.php
@@ -17,12 +17,8 @@ public function setUp() {
     }
 
     public function tearDown() {
-        ORM::configure('logging', false);
-        ORM::configure('logging', false, self::ALTERNATE);
-        ORM::configure('caching', false);
-        ORM::configure('caching', false, self::ALTERNATE);
-        ORM::set_db(null);
-        ORM::set_db(null, self::ALTERNATE);
+        ORM::reset_config();
+        ORM::reset_db();
     }
 
     // Test caching. This is a bit of a hack.

diff --git a/test/ConfigTest.php b/test/ConfigTest.php
@@ -14,10 +14,8 @@ public function setUp() {
     }
 
     public function tearDown() {
-        ORM::configure('logging', false);
-        ORM::set_db(null);
-
-        ORM::configure('id_column', 'id');
+        ORM::reset_config();
+        ORM::reset_db();
     }
 
     protected function setUpIdColumnOverrides() {
@@ -118,6 +116,7 @@ public function testGetConfigArray() {
             'logger' => null,
             'caching' => false,
             'return_result_sets' => false,
+            'limit_clause_style' => 'limit',
         );
         $this->assertEquals($expected, ORM::get_config());
     }

diff --git a/test/IdiormResultSetTest.php b/test/IdiormResultSetTest.php
@@ -12,8 +12,8 @@ public function setUp() {
     }
 
     public function tearDown() {
-        ORM::configure('logging', false);
-        ORM::set_db(null);
+        ORM::reset_config();
+        ORM::reset_db();
     }
 
     public function testGet() {

diff --git a/test/MulitpleConnectionTest.php b/test/MulitpleConnectionTest.php
@@ -15,10 +15,8 @@ public function setUp() {
     }
 
     public function tearDown() {
-        ORM::configure('logging', false);
-        ORM::configure('logging', false, self::ALTERNATE);
-        ORM::set_db(null);
-        ORM::set_db(null, self::ALTERNATE);
+        ORM::reset_config();
+        ORM::reset_db();
     }
 
     public function testMultiplePdoConnections() {

diff --git a/test/ORMTest.php b/test/ORMTest.php
@@ -12,8 +12,8 @@ public function setUp() {
     }
 
     public function tearDown() {
-        ORM::configure('logging', false);
-        ORM::set_db(null);
+        ORM::reset_config();
+        ORM::reset_db();
     }
 
     public function testStaticAtrributes() {

diff --git a/test/QueryBuilderMssqlTest.php b/test/QueryBuilderMssqlTest.php
@@ -0,0 +1,32 @@
+<?php
+
+class QueryBuilderMssqlTest extends PHPUnit_Framework_TestCase {
+
+    public function setUp() {
+        // Enable logging
+        ORM::configure('logging', true);
+
+        // Set up the dummy database connection
+        $db = new MockMsSqlPDO('sqlite::memory:');
+        ORM::set_db($db);
+    }
+
+    public function tearDown() {
+        ORM::reset_config();
+        ORM::reset_db();
+    }
+
+    public function testFindOne() {
+        ORM::for_table('widget')->find_one();
+        $expected = 'SELECT TOP 1 * FROM "widget"';
+        $this->assertEquals($expected, ORM::get_last_query());
+    }
+
+    public function testLimit() {
+        ORM::for_table('widget')->limit(5)->find_many();
+        $expected = 'SELECT TOP 5 * FROM "widget"';
+        $this->assertEquals($expected, ORM::get_last_query());
+    }
+
+}
+
diff --git a/test/QueryBuilderTest.php b/test/QueryBuilderTest.php
@@ -12,8 +12,8 @@ public function setUp() {
     }
 
     public function tearDown() {
-        ORM::configure('logging', false);
-        ORM::set_db(null);
+        ORM::reset_config();
+        ORM::reset_db();
     }
 
     public function testFindMany() {

diff --git a/test/bootstrap.php b/test/bootstrap.php
@@ -38,7 +38,7 @@ class MockDifferentPDOStatement extends MockPDOStatement { }
  *
  */
 class MockPDO extends PDO {
-
+   
    /**
     * Return a dummy PDO statement
     */
@@ -62,3 +62,23 @@ public function prepare($statement, $driver_options = array()) {
         return $this->last_query;
     }
 }
+
+class MockMsSqlPDO extends MockPDO {
+
+   public $fake_driver = 'mssql';
+
+   /**
+    * If we are asking for the name of the driver, check if a fake one
+    * has been set.
+    */
+    public function getAttribute($attribute) {
+        if ($attribute == self::ATTR_DRIVER_NAME) {
+            if (!is_null($this->fake_driver)) {
+                return $this->fake_driver;
+            }
+        }
+
+        return parent::getAttribute($attribute);
+    }
+
+}