While I searched SQL information I ran into page that discusses
database management systems and their standards compliance and to my
satisfaction PostgreSQL scored high in this evaluation.
As there is always room for improvements, perhaps the development team
could read this document and record some of the raised inssues into
the TODO list to strive for even better standards compliance in future
releases:
Comparison of different SQL implementations http://troels.arvin.dk/db/rdbms/ by Troels Arvin
<troels@arvin.dk>
I cannot comment how up to date this listing is. If there are errors,
please kindly notify updates to the page maintainer.
Jari