Merge pull request #3049 from resurtm/db-connection-odbc

docs/guide/database-basics.md

@@ -44,6 +44,20 @@ return [
 ];
 ```
 
+There is a peculiarity when you want to work with the database through the `ODBC` layer. When using `ODBC`,
+connection `DSN` doesn't indicate uniquely what database type is being used. That's why you have to override
+`driverName` property of [[yii\db\Connection]] class to disambiguate that:
+
+```php
+'db' => [
+	'class' => 'yii\db\Connection',
+	'driverName' => 'mysql',
+	'dsn' => 'odbc:Driver={MySQL};Server=localhost;Database=test',
+	'username' => 'root',
+	'password' => '',
+],
+```
+
 Please refer to the [PHP manual](http://www.php.net/manual/en/function.PDO-construct.php) for more details
 on the format of the DSN string.
 

framework/CHANGELOG.md

@@ -190,6 +190,7 @@ Yii Framework 2 Change Log
 - Enh: Improved action filter and action execution flow by supporting installing action filters at controller, module and application levels (qiangxue)
 - Enh: Added `isAssociative()` and `isIndexed()` to `yii\helpers\ArrayHelper` (qiangxue)
 - Enh: Added `addSelect` to `yii\db\Query` (Alex-Code)
+- Enh: Added ODBC support in `yii\db\Connection` (nineinchnick, resurtm)
 - Chg #47: Changed Markdown library to cebe/markdown and adjusted Markdown helper API (cebe)
 - Chg #735: Added back `ActiveField::hiddenInput()` (qiangxue)
 - Chg #1186: Changed `Sort` to use comma to separate multiple sort fields and use negative sign to indicate descending sort (qiangxue)

framework/db/Connection.php

@@ -89,7 +89,8 @@ use yii\caching\Cache;
  * ]
  * ~~~
  *
- * @property string $driverName Name of the DB driver. This property is read-only.
+ * @property string $driverName Name of the DB driver. Change this property if you want to override the
+ * driver name specified in [[dsn]]. This can be useful if you're working with the database via ODBC layer.
  * @property boolean $isActive Whether the DB connection is established. This property is read-only.
  * @property string $lastInsertID The row ID of the last row inserted, or the last value retrieved from the
  * sequence object. This property is read-only.
@@ -261,6 +262,10 @@ class Connection extends Component
      * @var Schema the database schema
      */
     private $_schema;
+    /**
+     * @var string driver name
+     */
+    private $_driverName;
 
     /**
      * Returns a value indicating whether the DB connection is established.
@@ -348,11 +353,13 @@ class Connection extends Component
         $pdoClass = $this->pdoClass;
         if ($pdoClass === null) {
             $pdoClass = 'PDO';
-            if (($pos = strpos($this->dsn, ':')) !== false) {
+            if ($this->_driverName !== null) {
+                $driver = $this->_driverName;
+            } elseif (($pos = strpos($this->dsn, ':')) !== false) {
                 $driver = strtolower(substr($this->dsn, 0, $pos));
-                if ($driver === 'mssql' || $driver === 'dblib' || $driver === 'sqlsrv') {
-                    $pdoClass = 'yii\db\mssql\PDO';
             }
+            if (isset($driver) && ($driver === 'mssql' || $driver === 'dblib' || $driver === 'sqlsrv')) {
+                $pdoClass = 'yii\db\mssql\PDO';
             }
         }
 
@@ -533,17 +540,29 @@ class Connection extends Component
     }
 
     /**
-     * Returns the name of the DB driver for the current [[dsn]].
+     * Returns the name of the DB driver. Based on the the current [[dsn]], in case it was not set explicitly
+     * by an end user.
      * @return string name of the DB driver
      */
     public function getDriverName()
     {
+        if ($this->_driverName === null) {
             if (($pos = strpos($this->dsn, ':')) !== false) {
-            return strtolower(substr($this->dsn, 0, $pos));
+                $this->_driverName = strtolower(substr($this->dsn, 0, $pos));
             } else {
                 $this->open();
-
-            return strtolower($this->pdo->getAttribute(PDO::ATTR_DRIVER_NAME));
+                $this->_driverName = strtolower($this->pdo->getAttribute(PDO::ATTR_DRIVER_NAME));
             }
         }
+        return $this->_driverName;
+    }
+
+    /**
+     * Changes the current driver name.
+     * @param string $driverName name of the DB driver
+     */
+    public function setDriverName($driverName)
+    {
+        $this->_driverName = strtolower($driverName);
+    }
 }