What is SQL/PSM and how does it differ from other versions of SQL like T-SQL?

I've wik开发者_高级运维i'd SQL/PSM and I know it stands for Structured Query Language/Pesistent Stored Modules. I'd like to know what it really is and how it differs from T-SQL and any other versions of SQL?

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SQL-PSM is an ISO standard like SQL. But since SQL does not have procedural capabilities, SQL-PSM came in to extend SQL to define those capabilities.

There is a wikipedia entry for SQL-PSM.

There are many commercial databases which implement this standard. IBM DB2, MySQL and PostgreSQL e.t.c. Taken from wikipedia entry for SQL.

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I think... PSM is just a generic term for "Stored Procedure" in TSQL.

A stored procedure is basically just a bunch of TSQL (can be as simple as a single SELECT statement, or as complicated as you please) that can take parameters, execute DML / DDL / and other operations, and report on it's final status (success or failure) that gets compiled into a single execution plan.

Also known a Stored Procedure or just 'Procedure' in PL/SQL -- it's basically the same thing there.

SQLlite doesn't have stored prodecures...

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Persistent Stored Modules exist in many different database technologies. Their interfaces are different and the actual declarations and out can be different as well. But in general, it is a way of keeping SQL programming code & logic bundled at the SQL server level.