diff --git a/process/Sql_lib/process.js b/process/Sql_lib/process.js
index 0dfe9541988348a0245357430c4c6724ad5135b7..38ded284bedb1364efe3d27988d1168ca7e4ce51 100644
--- a/process/Sql_lib/process.js
+++ b/process/Sql_lib/process.js
@@ -390,12 +390,28 @@ SqlCondition.prototype._prepare = function(field, value, cond, fieldType) {
     
     if (typeof field === 'string')
     {
-        alias = field;
+        var pointPos = field.indexOf(".");
+        
+        if (pointPos > 0 && pointPos < field.length-1)
+        {
+            alias = field;
+        }
+        else
+        {
+            throw new Error(translate.withArguments("${SQL_LIB_FIELD_WRONG_FORMAT} field: %0", [field]));
+        }
     }
     else
     {
-        alias = field[2] + "." + field[1];
-        field = field[0] + "." + field[1];
+        if (field.length == 3)
+        {
+            alias = field[2] + "." + field[1];
+            field = field[0] + "." + field[1];
+        }
+        else
+        {
+            throw new Error(translate.withArguments("${SQL_LIB_FIELD_WRONG_FORMAT} field: %0", [field.toSource()]));
+        }
     }
     
     var type;