Execute postgreSQL stored procedure as one transac

问题:

I'm using PostgreSQL 9.3 and I have some stored procedures created which contains several statements. I'm calling this stored procedures in a Java application with the help of a prepared statement.

Now I've read that each statement inside the stored procedure is executed as a transaction, i.e. one commit after each statement. But what I want is to have the whole stored procedure executed as one transaction, i.e. only one commit.

How can I do this? Perhaps deactivating autocommit on the JDBC level?

回答1:

Well, basically stored procedures are atomic in nature and executed as one transaction.

CREATE TABLE xxx (id int PRIMARY KEY);

CREATE OR REPLACE FUNCTION f() RETURNS void AS $$
DECLARE
  len int;
BEGIN
  RAISE NOTICE 'Transaction ID: %', TXID_CURRENT();
  INSERT INTO xxx VALUES (1);

  RAISE NOTICE 'Transaction ID: %', TXID_CURRENT();
  INSERT INTO xxx VALUES (2);

  RAISE NOTICE 'Transaction ID: %', TXID_CURRENT();
  SELECT COUNT(*) FROM xxx INTO len;
  RAISE NOTICE 'Number of records: %', len;

  RAISE NOTICE 'Transaction ID: %', TXID_CURRENT();

  -- results in unique constraint violation
  UPDATE xxx SET id = 3;
END;
$$ LANGUAGE plpgsql;

Then try invoking f() from psql.

stackoverflow=# show autocommit;
 autocommit 
------------
 on
(1 row)

stackoverflow=# SELECT f();
NOTICE:  Transaction ID: 15086
NOTICE:  Transaction ID: 15086
NOTICE:  Transaction ID: 15086
NOTICE:  Number of records: 2
NOTICE:  Transaction ID: 15086
ERROR:  duplicate key value violates unique constraint "xxx_pkey"
DETAIL:  Key (id)=(3) already exists.
CONTEXT:  SQL statement "UPDATE xxx SET id = 3"
PL/pgSQL function f() line 20 at SQL statement

stackoverflow=# SELECT * FROM xxx;
id 
----
(0 rows)