Package Supporting Autonomous Transaction
gaussdb=# create database test DBCOMPATIBILITY = 'ORA';
CREATE DATABASE
test=# \c test
-- Create a table.
test=# CREATE TABLE t2(a INT, b INT);
NOTICE: The 'DISTRIBUTE BY' clause is not specified. Using 'a' as the distribution column by default.
HINT: Please use 'DISTRIBUTE BY' clause to specify suitable data distribution column.
CREATE TABLE
test=# INSERT INTO t2 VALUES(1,2);
INSERT 0 1
test=# SELECT * FROM t2;
a | b
---+---
1 | 2
(1 row)
-- Create a stored procedure or function in a package that contains autonomous transactions.
test=# CREATE OR REPLACE PACKAGE autonomous_pkg AS
PROCEDURE autonomous_4(a INT, b INT);
FUNCTION autonomous_32(a INT ,b INT) RETURN INT;
END autonomous_pkg;
/
CREATE PACKAGE
test=# CREATE OR REPLACE PACKAGE BODY autonomous_pkg AS
PROCEDURE autonomous_4(a INT, b INT) AS
DECLARE
num3 INT := a;
num4 INT := b;
PRAGMA AUTONOMOUS_TRANSACTION;
BEGIN
INSERT INTO t2 VALUES(num3, num4);
END;
FUNCTION autonomous_32(a INT ,b INT) RETURN INT AS
DECLARE
PRAGMA AUTONOMOUS_TRANSACTION;
BEGIN
INSERT INTO t2 VALUES(a, b);
RETURN 1;
END;
END autonomous_pkg;
/
CREATE PACKAGE BODY
-- Create a common stored procedure that calls a stored procedure or function from a package that contains autonomous transactions.
test=# CREATE OR REPLACE PROCEDURE autonomous_5(a INT, b INT) AS
DECLARE
va INT;
BEGIN
INSERT INTO t2 VALUES(666, 666);
autonomous_pkg.autonomous_4(a,b);
va := autonomous_pkg.autonomous_32(a + 1, b + 1);
ROLLBACK;
END;
/
CREATE PROCEDURE
-- Call a common stored procedure.
test=# SELECT autonomous_5(11,22);
autonomous_5
--------------
(1 row)
-- View the table result.
test=# SELECT * FROM t2 ORDER BY a;
a | b
----+----
1 | 2
11 | 22
12 | 23
(3 rows)
test=# DROP TABLE t2;
DROP TABLE In the preceding example, a stored procedure or function in a package containing autonomous transactions is finally executed in a transaction block that is rolled back, which directly illustrates a characteristic of the autonomous transaction, that is, rollback of the primary transaction does not affect content that has been committed by an autonomous transaction.