What is the history of the SQL Server ANSI (ISO) compatibility settings?
SQL Server came from Sybase, which had different default settings for these kind of things. Gradually, MS introduced SET settings to allow us to control behavoiur. A big push to follow ANSI standard was with the 6.0 release in 1995. I believe they even hired Joe Celko with the work to be ANSI SQL certified (yes, there was a certification process back in the days - anybody ever used SET FIPS_FLAGGER? :-)). This was when the specific SET ANSI setting was inroduced - to allow us to &quot;be ANSI&quot; with only one setting. But this is all a mess with the combo of database settings (which are largely ignored) along with different APIs and tools that has different combo of these settings.