What is the difference between SQL, PL-SQL and T-SQL SQL is a query language to operate on sets. It is more or less standardized, and used by almost all relational database management systems: SQL Server, Oracle, MySQL, PostgreSQL, DB2, Informix, etc. PL/SQL is a proprietary procedural language used by Oracle PL/pgSQL is a procedural language used by PostgreSQL T-SQL is a proprietary procedural language used by Microsoft in SQL Server. Procedural languages are designed to extend SQL's abilities while being able to integrate well with SQL. Several features such as local variables and string/data processing are added. These features make the language Turing-complete. 1. SQL or Structured Query Language was developed by IBM for their product "System R". Later ANSI made it as a Standard on which all Query Languages are based upon and have extended this to create their own DataBase Query Language suits. The first standard was ...