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|
# name: test/sql/update/test_update_many_updaters.test
# description: Test update behavior with multiple updaters
# group: [update]
statement ok
SET immediate_transaction_mode=true
# this test contains four query connections (con1, con2, con3, con4)
# and one updating connection (updater)
# first create a table, filled with 3 values (1), (2), (3)
statement ok con1
CREATE TABLE test (a INTEGER);
statement ok con1
INSERT INTO test VALUES (1), (2), (3)
# now we start updating specific values and reading different versions
# con1 sees the initial state
statement ok con1
BEGIN TRANSACTION
statement ok updater
UPDATE test SET a=4 WHERE a=1
statement ok con2
BEGIN TRANSACTION
statement ok updater
UPDATE test SET a=5 WHERE a=2
statement ok con3
BEGIN TRANSACTION
statement ok updater
UPDATE test SET a=6 WHERE a=3
statement ok con4
BEGIN TRANSACTION
# now read the different states
# con sees {1, 2, 3}
query I con1
SELECT * FROM test ORDER BY a
----
1
2
3
# con2 sees {2, 3, 4}
query I con2
SELECT * FROM test ORDER BY a
----
2
3
4
# con3 sees {3, 4, 5}
query I con3
SELECT * FROM test ORDER BY a
----
3
4
5
# con4 sees {4, 5, 6}
query I con4
SELECT * FROM test ORDER BY a
----
4
5
6
# now verify that we get conflicts when we update values that have been updated AFTER we started
statement error con1
UPDATE test SET a=99 WHERE a=1
----
statement error con2
UPDATE test SET a=99 WHERE a=2
----
statement error con3
UPDATE test SET a=99 WHERE a=3
----
# revert to previous state
statement ok updater
UPDATE test SET a=a-3
# rollback all connections
statement ok con1
ROLLBACK
statement ok con2
ROLLBACK
statement ok con3
ROLLBACK
statement ok con4
ROLLBACK
# we repeat the previous process of updates
statement ok con1
BEGIN TRANSACTION
statement ok updater
UPDATE test SET a=4 WHERE a=1
statement ok con2
BEGIN TRANSACTION
statement ok updater
UPDATE test SET a=5 WHERE a=2
statement ok con3
BEGIN TRANSACTION
statement ok updater
UPDATE test SET a=6 WHERE a=3
statement ok con4
BEGIN TRANSACTION
# now read the different states
# con sees {1, 2, 3}
query I con1
SELECT * FROM test ORDER BY a
----
1
2
3
# con2 sees {2, 3, 4}
query I con2
SELECT * FROM test ORDER BY a
----
2
3
4
# con3 sees {3, 4, 5}
query I con3
SELECT * FROM test ORDER BY a
----
3
4
5
# con4 sees {4, 5, 6}
query I con4
SELECT * FROM test ORDER BY a
----
4
5
6
# we now verify that we CAN update values that were committed BEFORE we started
statement ok con2
UPDATE test SET a=7 WHERE a=4
statement ok con3
UPDATE test SET a=8 WHERE a=5
statement ok con4
UPDATE test SET a=9 WHERE a=6
# now read the different states again
# con sees {1, 2, 3} still
query I con1
SELECT * FROM test ORDER BY a
----
1
2
3
# con2 sees {2, 3, 7}
query I con2
SELECT * FROM test ORDER BY a
----
2
3
7
# con3 sees {3, 4, 8}
query I con3
SELECT * FROM test ORDER BY a
----
3
4
8
# con4 sees {4, 5, 9}
query I con4
SELECT * FROM test ORDER BY a
----
4
5
9
# updater still sees {4, 5, 6}
query I updater
SELECT * FROM test ORDER BY a
----
4
5
6
# now we commit in phases
# first we commit con4
statement ok con4
COMMIT
# con, con2, con3 still see the same data, con4 sees the currently committed data
query I con1
SELECT * FROM test ORDER BY a
----
1
2
3
query I con2
SELECT * FROM test ORDER BY a
----
2
3
7
query I con3
SELECT * FROM test ORDER BY a
----
3
4
8
query I con4
SELECT * FROM test ORDER BY a
----
4
5
9
# then we commit con2
statement ok con2
COMMIT
# con, con3 still see the same data, con2 and con4 see the committed data
query I con1
SELECT * FROM test ORDER BY a
----
1
2
3
query I con2
SELECT * FROM test ORDER BY a
----
5
7
9
query I con3
SELECT * FROM test ORDER BY a
----
3
4
8
query I con4
SELECT * FROM test ORDER BY a
----
5
7
9
# then we commit con3
statement ok con3
COMMIT
# con still sees the same data, but the rest all see the committed data
query I con1
SELECT * FROM test ORDER BY a
----
1
2
3
query I con2
SELECT * FROM test ORDER BY a
----
7
8
9
query I con3
SELECT * FROM test ORDER BY a
----
7
8
9
query I con4
SELECT * FROM test ORDER BY a
----
7
8
9
# now we commit con1, this should trigger a cleanup
statement ok con1
COMMIT
# now con1 also sees the committed data
query I con1
SELECT * FROM test ORDER BY a
----
7
8
9
|
