GaussDB(DWS) SQL

What Is SQL?

SQL is a standard computer language used to control the access to databases and manage data in databases.

SQL provides different statements to enable you to:

• Query data.
• Insert, update, and delete rows.
• Create, replace, modify, and delete objects.
• Control the access to a database and its objects.
• Maintain the consistency and integrity of a database.

SQL consists of commands and functions that are used to manage databases and database objects. SQL can also forcibly implement the rules for data types, expressions, and texts. Therefore, section "SQL Reference" describes data types, expressions, functions, and operators in addition to SQL syntax.

Development of SQL Standards

Released SQL standards are as follows:

• 1986: ANSI X3.135-1986, ISO/IEC 9075:1986, SQL-86
• 1989: ANSI X3.135-1989, ISO/IEC 9075:1989, SQL-89
• 1992: ANSI X3.135-1992, ISO/IEC 9075:1992, SQL-92 (SQL2)
• 1999: ISO/IEC 9075:1999, SQL:1999 (SQL3)
• 2003: ISO/IEC 9075:2003, SQL:2003 (SQL4)
• 2011: ISO/IEC 9075:200N, SQL:2011 (SQL5)

Supported SQL Standards

GaussDB(DWS) is compatible with Postgres-XC features and supports the major features of SQL2, SQL3, and SQL4 by default.