Difference between revisions of "SAVEPOINT"

Revision as of 13:05, 26 May 2009

Class

SQL Applications

Purpose

Identifies a stage within a transaction which can subsequently be used as ROLLBACK point.

Syntax

SAVEPOINT <savepoint>

See Also

BEGIN TRANSACTION, COMMIT, END TRANSACTION, ROLLBACK, SAVE TRANSACTION, SET TRANSACTION, TXNISOLATION(), TXNLEVEL()

Description

The SAVEPOINT statement identifies a stage within a transaction which can subsequently be used as ROLLBACK point. The name of the savepoint is specified in <savepoint>.

Issuing the SAVEPOINT <savepoint> statement causes the TXNLEVEL() to increase by 1. If the transaction is rolled back to the <savepoint> using the ROLLBACK command, the TXNLEVEL will decrease by 1 and a partial rollback of the transaction will be carried out. Changes made since the specified <savepoint> was declared are discarded and the transaction continues from the <savepoint>.

A transaction is a sequence of SQL statements that Recital treats as a single unit. A transaction begins with the first executable SQL statement after a BEGIN TRANSACTION. A transaction ends with a COMMIT, ROLLBACK or END TRANSACTION.

Example

// config.db
set sql to recital
set sql on
// end of config.db
 
// SAVEPOINT <savepoint> 
BEGIN TRANSACTION parent_and_child;
  INSERT INTO customer
    (TITLE, LAST_NAME, FIRST_NAME, INITIAL, STREET,
    CITY, STATE, ZIP,LIMIT, START_DATE)
    VALUES
    ('Ms', 'Jones', 'Susan', 'B', '177 High Street', 'Beverly', 'MA', '01915', 2000, date());
  SAVEPOINT parent_added;
  INSERT INTO accounts (ORD_VALUE) VALUES (30);
  ROLLBACK TRANSACTION parent_added;
END TRANSACTION;
// End of program

Products

Recital Database Server, Recital Mirage Server, Recital Terminal Developer