PostgreSQLImplementation of programming language SQL
PostgreSQL is an object-relational database management system developed by PostgreSQL Global Development Group. It uses SQL as query language. It is distributed under MIT-style license and is available for multiple platforms.
- implements most features of SQL-2008 standard.
- ensures efficient maintenance of ACID principles (atomicity, consistency, isolation, durability).
- fully transactional, including DDL statements.
- if one needs procedural language, one can use either PL/plSQL (a built-in language similar to Oracle PL/SQL) or one of the other languages provided by PostgreSQL. The standard installation includes Tcl, Python and Perl, and there are plenty of others available as extensions.
Hello, World!:Example for versions Microsoft SQL Server 2005, Microsoft SQL Server 2008 R2, Microsoft SQL Server 2012, MySQL 3.23.57, PostgreSQL 9.1
select 'Hello, World!';
Factorial:Example for versions PostgreSQL 9.1
The task of factorials calculation is solved using standard methods only: a built-in factorial function
! (postfix form; there is also a prefix form
!!) and a set function
generate_series which generates a set of rows containing values between the first and the second parameters.
select n || '! = ' || (n!) from generate_series(0,16) as seq(n);
Fibonacci numbers:Example for versions PostgreSQL 9.1
WITH RECURSIVE t(a,b) AS ( VALUES(1,1) UNION ALL SELECT b, a + b FROM t WHERE b < 1000 ) SELECT array_to_string(array(SELECT a FROM t), ', ') || ', ...';