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CREATE TABLE test1 (a int, b text);
CREATE PROCEDURE transaction_test1()
LANGUAGE plpython3u
AS $$
for i in range(0, 10):
plpy.execute("INSERT INTO test1 (a) VALUES (%d)" % i)
if i % 2 == 0:
plpy.commit()
else:
plpy.rollback()
$$;
CALL transaction_test1();
SELECT * FROM test1;
a | b
---+---
0 |
2 |
4 |
6 |
8 |
(5 rows)
TRUNCATE test1;
DO
LANGUAGE plpython3u
$$
for i in range(0, 10):
plpy.execute("INSERT INTO test1 (a) VALUES (%d)" % i)
if i % 2 == 0:
plpy.commit()
else:
plpy.rollback()
$$;
SELECT * FROM test1;
a | b
---+---
0 |
2 |
4 |
6 |
8 |
(5 rows)
TRUNCATE test1;
-- not allowed in a function
CREATE FUNCTION transaction_test2() RETURNS int
LANGUAGE plpython3u
AS $$
for i in range(0, 10):
plpy.execute("INSERT INTO test1 (a) VALUES (%d)" % i)
if i % 2 == 0:
plpy.commit()
else:
plpy.rollback()
return 1
$$;
SELECT transaction_test2();
ERROR: spiexceptions.InvalidTransactionTermination: invalid transaction termination
CONTEXT: Traceback (most recent call last):
PL/Python function "transaction_test2", line 5, in <module>
plpy.commit()
PL/Python function "transaction_test2"
SELECT * FROM test1;
a | b
---+---
(0 rows)
-- also not allowed if procedure is called from a function
CREATE FUNCTION transaction_test3() RETURNS int
LANGUAGE plpython3u
AS $$
plpy.execute("CALL transaction_test1()")
return 1
$$;
SELECT transaction_test3();
ERROR: spiexceptions.InvalidTransactionTermination: spiexceptions.InvalidTransactionTermination: invalid transaction termination
CONTEXT: Traceback (most recent call last):
PL/Python function "transaction_test3", line 2, in <module>
plpy.execute("CALL transaction_test1()")
PL/Python function "transaction_test3"
SELECT * FROM test1;
a | b
---+---
(0 rows)
-- DO block inside function
CREATE FUNCTION transaction_test4() RETURNS int
LANGUAGE plpython3u
AS $$
plpy.execute("DO LANGUAGE plpython3u $x$ plpy.commit() $x$")
return 1
$$;
SELECT transaction_test4();
ERROR: spiexceptions.InvalidTransactionTermination: spiexceptions.InvalidTransactionTermination: invalid transaction termination
CONTEXT: Traceback (most recent call last):
PL/Python function "transaction_test4", line 2, in <module>
plpy.execute("DO LANGUAGE plpython3u $x$ plpy.commit() $x$")
PL/Python function "transaction_test4"
-- commit inside subtransaction (prohibited)
DO LANGUAGE plpython3u $$
s = plpy.subtransaction()
s.enter()
plpy.commit()
$$;
WARNING: forcibly aborting a subtransaction that has not been exited
ERROR: spiexceptions.InvalidTransactionTermination: cannot commit while a subtransaction is active
CONTEXT: Traceback (most recent call last):
PL/Python anonymous code block, line 4, in <module>
plpy.commit()
PL/Python anonymous code block
-- commit inside cursor loop
CREATE TABLE test2 (x int);
INSERT INTO test2 VALUES (0), (1), (2), (3), (4);
TRUNCATE test1;
DO LANGUAGE plpython3u $$
for row in plpy.cursor("SELECT * FROM test2 ORDER BY x"):
plpy.execute("INSERT INTO test1 (a) VALUES (%s)" % row['x'])
plpy.commit()
$$;
SELECT * FROM test1;
a | b
---+---
0 |
1 |
2 |
3 |
4 |
(5 rows)
-- check that this doesn't leak a holdable portal
SELECT * FROM pg_cursors;
name | statement | is_holdable | is_binary | is_scrollable | creation_time
------+-----------+-------------+-----------+---------------+---------------
(0 rows)
-- error in cursor loop with commit
TRUNCATE test1;
DO LANGUAGE plpython3u $$
for row in plpy.cursor("SELECT * FROM test2 ORDER BY x"):
plpy.execute("INSERT INTO test1 (a) VALUES (12/(%s-2))" % row['x'])
plpy.commit()
$$;
ERROR: spiexceptions.DivisionByZero: division by zero
CONTEXT: Traceback (most recent call last):
PL/Python anonymous code block, line 3, in <module>
plpy.execute("INSERT INTO test1 (a) VALUES (12/(%s-2))" % row['x'])
PL/Python anonymous code block
SELECT * FROM test1;
a | b
-----+---
-6 |
-12 |
(2 rows)
SELECT * FROM pg_cursors;
name | statement | is_holdable | is_binary | is_scrollable | creation_time
------+-----------+-------------+-----------+---------------+---------------
(0 rows)
-- rollback inside cursor loop
TRUNCATE test1;
DO LANGUAGE plpython3u $$
for row in plpy.cursor("SELECT * FROM test2 ORDER BY x"):
plpy.execute("INSERT INTO test1 (a) VALUES (%s)" % row['x'])
plpy.rollback()
$$;
SELECT * FROM test1;
a | b
---+---
(0 rows)
SELECT * FROM pg_cursors;
name | statement | is_holdable | is_binary | is_scrollable | creation_time
------+-----------+-------------+-----------+---------------+---------------
(0 rows)
-- first commit then rollback inside cursor loop
TRUNCATE test1;
DO LANGUAGE plpython3u $$
for row in plpy.cursor("SELECT * FROM test2 ORDER BY x"):
plpy.execute("INSERT INTO test1 (a) VALUES (%s)" % row['x'])
if row['x'] % 2 == 0:
plpy.commit()
else:
plpy.rollback()
$$;
SELECT * FROM test1;
a | b
---+---
0 |
2 |
4 |
(3 rows)
SELECT * FROM pg_cursors;
name | statement | is_holdable | is_binary | is_scrollable | creation_time
------+-----------+-------------+-----------+---------------+---------------
(0 rows)
-- check handling of an error during COMMIT
CREATE TABLE testpk (id int PRIMARY KEY);
CREATE TABLE testfk(f1 int REFERENCES testpk DEFERRABLE INITIALLY DEFERRED);
DO LANGUAGE plpython3u $$
# this insert will fail during commit:
plpy.execute("INSERT INTO testfk VALUES (0)")
plpy.commit()
plpy.warning('should not get here')
$$;
ERROR: spiexceptions.ForeignKeyViolation: insert or update on table "testfk" violates foreign key constraint "testfk_f1_fkey"
DETAIL: Key (f1)=(0) is not present in table "testpk".
CONTEXT: Traceback (most recent call last):
PL/Python anonymous code block, line 4, in <module>
plpy.commit()
PL/Python anonymous code block
SELECT * FROM testpk;
id
----
(0 rows)
SELECT * FROM testfk;
f1
----
(0 rows)
DO LANGUAGE plpython3u $$
# this insert will fail during commit:
plpy.execute("INSERT INTO testfk VALUES (0)")
try:
plpy.commit()
except Exception as e:
plpy.info('sqlstate: %s' % (e.sqlstate))
# these inserts should work:
plpy.execute("INSERT INTO testpk VALUES (1)")
plpy.execute("INSERT INTO testfk VALUES (1)")
$$;
INFO: sqlstate: 23503
SELECT * FROM testpk;
id
----
1
(1 row)
SELECT * FROM testfk;
f1
----
1
(1 row)
DROP TABLE test1;
DROP TABLE test2;
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