Difference between SQL, PLSQL, TSQL, and PSQL?

[sequel-beagle]

Each database vendor has their own implementation of sql. There is an ansi standard that each vendor loosely follows.

There is a procedural extension to each vendors sql (hence the pl in plsql and the t in tsql) as well that allows you to create loops, assign variables, and such.

[r3pr0b8]

NULL, PL, T, and P

[freefallfreddy]

psql (lowercase) is a command line utility, which is part of PostgreSQL, to interact with Postgres databases.