From b3753c3c5dc36402976ac6f7ed4c4ae3ecf108f5 Mon Sep 17 00:00:00 2001
From: pokeeffe-molecula <85502298+pokeeffe-molecula@users.noreply.github.com>
Date: Thu, 27 Oct 2022 13:11:14 -0500
Subject: [PATCH] tightened up is/is not null filter expressions (FB-1741)
 (#2260)

Covers tightening up handling filter expressions that contain is/is not null ops. These filters may have to be translated into PQL calls to be passed to the executor and even though sql3 language supports nullability for any data type, currently only BSI fields are nullable at the storage engine level (there is a ticket to add support for non-BSI field here FB-1689: IS SQL Argument returns incorrect error) so when these fields are used in filter conditions we need to handle BSI and non-BSI fields differently.