diff --git a/classes/xml/xmlquery/DBParser.class.php b/classes/xml/xmlquery/DBParser.class.php
index 111f698f4..a8f961371 100644
--- a/classes/xml/xmlquery/DBParser.class.php
+++ b/classes/xml/xmlquery/DBParser.class.php
@@ -144,7 +144,7 @@
 					if(strpos($match,')') !== false) continue;
 					if(in_array($match, array(',', '.'))) continue;
 					if($brackets == $total_brackets){
-						if(!is_numeric($match)) {
+						if(!is_numeric($match) && !in_array(strtoupper($match), array('UNSIGNED', 'INTEGER', 'AS'))) {
 							$match = $this->escapeColumnExpression($match);	
 						}
 					}
diff --git a/tests/classes/db/db/xml_query/mysql/MysqlSelectTest.php b/tests/classes/db/db/xml_query/mysql/MysqlSelectTest.php
index 11741a2eb..6471e8022 100644
--- a/tests/classes/db/db/xml_query/mysql/MysqlSelectTest.php
+++ b/tests/classes/db/db/xml_query/mysql/MysqlSelectTest.php
@@ -380,4 +380,26 @@ class MysqlSelectTest extends MysqlTest {
                         limit 5";
         $this->_test($xml_file, $argsString, $expected);
     }
+
+	/**
+	 * Add support for CAST / CONVERT function
+	 */
+	function testCast()
+	{
+		$xml_file = _TEST_PATH_ . "db/xml_query/mysql/data/cast.xml";
+		$argsString = '';
+		$expected = "select cast(`document_srl` as unsigned integer) from `xe_documents` as `documents`";
+		$this->_test($xml_file, $argsString, $expected);
+	}
+
+	/**
+	 * Add support for CAST / CONVERT function
+	 */
+	function testConvert()
+	{
+		$xml_file = _TEST_PATH_ . "db/xml_query/mysql/data/convert.xml";
+		$argsString = '';
+		$expected = "select convert(`document_srl`, unsigned integer) from `xe_documents` as `documents`";
+		$this->_test($xml_file, $argsString, $expected);
+	}
 }
\ No newline at end of file
diff --git a/tests/classes/db/db/xml_query/mysql/data/cast.xml b/tests/classes/db/db/xml_query/mysql/data/cast.xml
new file mode 100644
index 000000000..9049dbe1b
--- /dev/null
+++ b/tests/classes/db/db/xml_query/mysql/data/cast.xml
@@ -0,0 +1,8 @@
+<query id="getDocumentListWithinComment" action="select">
+    <tables>
+        <table name="documents" alias="documents" />
+    </tables>
+    <columns>
+        <column name="CAST(document_srl as UNSIGNED INTEGER)" />
+    </columns>
+</query>
diff --git a/tests/classes/db/db/xml_query/mysql/data/convert.xml b/tests/classes/db/db/xml_query/mysql/data/convert.xml
new file mode 100644
index 000000000..96d982717
--- /dev/null
+++ b/tests/classes/db/db/xml_query/mysql/data/convert.xml
@@ -0,0 +1,8 @@
+<query id="getDocumentListWithinComment" action="select">
+    <tables>
+        <table name="documents" alias="documents" />
+    </tables>
+    <columns>
+        <column name="CONVERT(document_srl, UNSIGNED INTEGER)" />
+    </columns>
+</query>