Disable SQL override parser

Entering a valid query in Lookup SQL Override might result in session failure with "Contact Informatica Global Support" message. You copy the query from log and it runs great in your SQL client, so why does it fail?
The reason for this might be the subquery.

For some reason the parser fails to check the query and refuses to run it. You may try to disable parser in one of two ways:

To use nested loops in a Lookup SQL override do the following:

1. Add the lookupOverrideParsingSetting custom property to the Integration Service in the Administration Console and set the value as 1:

   LookupOverrideParsingSetting=1

2. Restart the Integration Service.

An alternative solution is to enter the custom property on session level:

1. Open the session settings and choose the Config Object tab.
2. In the Advanced Properties section choose Custom Properties.
3. Ensure to us the lower case 'l' instead of an upper case 'L'. Otherwise it won't work.

lookupOverrideParsingSetting=1

For full explanation refer to KB doc id 15532.