Fix #18229: Add a flag to set Connection to SyBase mode

Co-authored-by: Alexander Makarov <sam@rmcreative.ru>

framework/CHANGELOG.md

@@ -5,6 +5,7 @@ Yii Framework 2 Change Log
 ------------------------
 
 - Bug #18233: Add PHP 8 support (samdark)
+- Bug #18229: Add flag for recognize SyBase databases on uses pdo_dblib (darkdef)
 
 
 2.0.37 August 07, 2020

framework/db/Connection.php

@@ -418,6 +418,11 @@ class Connection extends Component
      * @see enableLogging
      */
     public $enableProfiling = true;
+    /**
+     * @var bool If the database connected via pdo_dblib is SyBase.
+     * @since 2.0.38
+     */
+    public $isSybase = false;
 
     /**
      * @var Transaction the currently active transaction
@@ -720,7 +725,7 @@ class Connection extends Component
                 $this->pdo->setAttribute(PDO::ATTR_EMULATE_PREPARES, $this->emulatePrepare);
             }
         }
-        if (in_array($this->getDriverName(), ['mssql', 'dblib'], true)) {
+        if (!$this->isSybase && in_array($this->getDriverName(), ['mssql', 'dblib'], true)) {
             $this->pdo->exec('SET ANSI_NULL_DFLT_ON ON');
         }
         if ($this->charset !== null && in_array($this->getDriverName(), ['pgsql', 'mysql', 'mysqli', 'cubrid'], true)) {