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SQL refers to Structured Query Language, a kind of language used to access, update and manipulate database. In SQL, ROLLBACK is a command that causes all data changes since the last START TRANSACTION or BEGIN to be discarded by the relational database management systems (RDBMS), so that the state of the data is "rolled back" to the way it was before those changes were made.
The grant, revoke syntax are as part of Database administration statementsàAccount Management System. The GRANT statement enables system administrators to grant privileges and roles, which can be granted to user accounts and roles. These syntax restrictions apply: GRANT cannot mix granting both privileges and roles in the same statement.
Issuing the commands ROLLBACK or COMMIT will also discard any savepoints created since the start of the main transaction. Savepoints are defined in the SQL standard and are supported by all established SQL relational databases, including PostgreSQL , Oracle Database , Microsoft SQL Server , MySQL , IBM Db2 , SQLite (since 3.6.8), Firebird , H2 ...
A COMMIT statement in SQL ends a transaction within a relational database management system (RDBMS) and makes all changes visible to other users. The general format is to issue a BEGIN WORK (or BEGIN TRANSACTION , depending on the database vendor) statement, one or more SQL statements, and then the COMMIT statement.
The syntax of the SQL programming language is defined and maintained by ISO/IEC SC 32 as part of ISO/IEC 9075. This standard is not freely available. This standard is not freely available. Despite the existence of the standard, SQL code is not completely portable among different database systems without adjustments.
Nonetheless, in systems such as Microsoft SQL Server, as well as connection technologies such as ODBC and Microsoft OLE DB, autocommit mode is the default for all statements that change data, in order to ensure that individual statements will conform to the ACID (atomicity-consistency-isolation-durability) properties of transactions.
Stored procedures written in non-SQL languages may or may not execute SQL statements themselves. The increasing adoption of stored procedures led to the introduction of procedural elements to the SQL language in the SQL:1999 and SQL:2003 standards in the part SQL/PSM. That made SQL an imperative programming language. Most database systems offer ...
SQL allows triggers to fire on updates to specific columns; As of version 9.0 of PostgreSQL this feature is also implemented in PostgreSQL. The standard allows the execution of a number of SQL statements other than SELECT, INSERT, UPDATE, such as CREATE TABLE as the triggered action. This can be done through creating a stored procedure or ...