mariadb/mysql-test/main/commit.test
Marko Mäkelä 3cef4f8f0f MDEV-515 Reduce InnoDB undo logging for insert into empty table
We implement an idea that was suggested by Michael 'Monty' Widenius
in October 2017: When InnoDB is inserting into an empty table or partition,
we can write a single undo log record TRX_UNDO_EMPTY, which will cause
ROLLBACK to clear the table.

For this to work, the insert into an empty table or partition must be
covered by an exclusive table lock that will be held until the transaction
has been committed or rolled back, or the INSERT operation has been
rolled back (and the table is empty again), in lock_table_x_unlock().

Clustered index records that are covered by the TRX_UNDO_EMPTY record
will carry DB_TRX_ID=0 and DB_ROLL_PTR=1<<55, and thus they cannot
be distinguished from what MDEV-12288 leaves behind after purging the
history of row-logged operations.

Concurrent non-locking reads must be adjusted: If the read view was
created before the INSERT into an empty table, then we must continue
to imagine that the table is empty, and not try to read any records.
If the read view was created after the INSERT was committed, then
all records must be visible normally. To implement this, we introduce
the field dict_table_t::bulk_trx_id.

This special handling only applies to the very first INSERT statement
of a transaction for the empty table or partition. If a subsequent
statement in the transaction is modifying the initially empty table again,
we must enable row-level undo logging, so that we will be able to
roll back to the start of the statement in case of an error (such as
duplicate key).

INSERT IGNORE will continue to use row-level logging and locking, because
implementing it would require the ability to roll back the latest row.
Since the undo log that we write only allows us to roll back the entire
statement, we cannot support INSERT IGNORE. We will introduce a
handler::extra() parameter HA_EXTRA_IGNORE_INSERT to indicate to storage
engines that INSERT IGNORE is being executed.

In many test cases, we add an extra record to the table, so that during
the 'interesting' part of the test, row-level locking and logging will
be used.

Replicas will continue to use row-level logging and locking until
MDEV-24622 has been addressed. Likewise, this optimization will be
disabled in Galera cluster until MDEV-24623 enables it.

dict_table_t::bulk_trx_id: The latest active or committed transaction
that initiated an insert into an empty table or partition.
Protected by exclusive table lock and a clustered index leaf page latch.

ins_node_t::bulk_insert: Whether bulk insert was initiated.

trx_t::mod_tables: Use C++11 style accessors (emplace instead of insert).
Unlike earlier, this collection will cover also temporary tables.

trx_mod_table_time_t: Add start_bulk_insert(), end_bulk_insert(),
is_bulk_insert(), was_bulk_insert().

trx_undo_report_row_operation(): Before accessing any undo log pages,
invoke trx->mod_tables.emplace() in order to determine whether undo
logging was disabled, or whether this is the first INSERT and we are
supposed to write a TRX_UNDO_EMPTY record.

row_ins_clust_index_entry_low(): If we are inserting into an empty
clustered index leaf page, set the ins_node_t::bulk_insert flag for
the subsequent trx_undo_report_row_operation() call.

lock_rec_insert_check_and_lock(), lock_prdt_insert_check_and_lock():
Remove the redundant parameter 'flags' that can be checked in the caller.

btr_cur_ins_lock_and_undo(): Simplify the logic. Correctly write
DB_TRX_ID,DB_ROLL_PTR after invoking trx_undo_report_row_operation().

trx_mark_sql_stat_end(), ha_innobase::extra(HA_EXTRA_IGNORE_INSERT),
ha_innobase::external_lock(): Invoke trx_t::end_bulk_insert() so that
the next statement will not be covered by table-level undo logging.

ReadView::changes_visible(trx_id_t) const: New accessor for the case
where the trx_id_t is not read from a potentially corrupted index page
but directly from the memory. In this case, we can skip a sanity check.

row_sel(), row_sel_try_search_shortcut(), row_search_mvcc():
row_sel_try_search_shortcut_for_mysql(),
row_merge_read_clustered_index(): Check dict_table_t::bulk_trx_id.

row_sel_clust_sees(): Replaces lock_clust_rec_cons_read_sees().

lock_sec_rec_cons_read_sees(): Replaced with lower-level code.

btr_root_page_init(): Refactored from btr_create().

dict_index_t::clear(), dict_table_t::clear(): Empty an index or table,
for the ROLLBACK of an INSERT operation.

ROW_T_EMPTY, ROW_OP_EMPTY: Note a concurrent ROLLBACK of an INSERT
into an empty table.

This is joint work with Thirunarayanan Balathandayuthapani,
who created a working prototype.
Thanks to Matthias Leich for extensive testing.
2021-01-25 18:41:27 +02:00

678 lines
14 KiB
Text

--source include/have_innodb.inc
connect (con1,localhost,root,,);
--echo #
--echo # Bug#20837 Apparent change of isolation level
--echo # during transaction
--echo #
--echo # Bug#53343 completion_type=1, COMMIT/ROLLBACK
--echo # AND CHAIN don't preserve the isolation
--echo # level
#
# A set of test cases that verifies operation of
# transaction isolation level and chaining is
# provided
# init
connection default;
SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ;
CREATE TABLE t1 (s1 INT) ENGINE=InnoDB;
INSERT INTO t1 VALUES (1),(2);
COMMIT;
#
# Verify that SET TRANS ISO LEVEL is not allowed
# inside a transaction
#
START TRANSACTION;
--error ER_CANT_CHANGE_TX_CHARACTERISTICS
SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
COMMIT;
#
# Verify consistent output from
# SELECT @@tx_isolation (Bug#20837)
#
# The transaction will be in READ UNCOMMITTED mode,
# but SELECT @@tx_isolation should report the session
# value, which is REPEATABLE READ
#
SET @@autocommit=0;
COMMIT;
SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
START TRANSACTION;
SELECT @@tx_isolation;
--echo Should be REPEATABLE READ
SELECT * FROM t1;
SELECT @@tx_isolation;
--echo Should be REPEATABLE READ
INSERT INTO t1 VALUES (-1);
SELECT @@tx_isolation;
--echo Should be REPEATABLE READ
COMMIT;
#
# Verify that a change in the session variable
# does not affect the currently started
# transaction
#
START TRANSACTION;
SELECT * FROM t1;
SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;
connection con1;
START TRANSACTION;
INSERT INTO t1 VALUES (1000);
COMMIT;
connection default;
--echo We should not be able to read the '1000'
SELECT * FROM t1;
COMMIT;
--echo Now, the '1000' should appear.
START TRANSACTION;
SELECT * FROM t1;
COMMIT;
# restore the session value
SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ;
#
# A set of test cases for verification that
# isolation level during chaining works. MySQL
# has three variants of chaining, i.e
# COMMIT AND CHAIN, ROLLBACK AND CHAIN, and
# the use of @completion_type
#
#
# Verify isolation level with COMMIT AND CHAIN
#
# COMMIT AND CHAIN causes a new transaction to
# begin as soon as the current ends, and the new
# transaction will have the same tran. iso. level
# as the first.
#
connection default;
SET TRANSACTION ISOLATION LEVEL READ COMMITTED;
START TRANSACTION;
connection con1;
START TRANSACTION;
INSERT INTO t1 VALUES (1001);
COMMIT;
connection default;
SELECT COUNT(*) FROM t1 WHERE s1 = 1001;
--echo Should be 1
COMMIT AND CHAIN;
connection con1;
INSERT INTO t1 VALUES (1002);
COMMIT;
connection default;
SELECT COUNT(*) FROM t1 WHERE s1 = 1002;
--echo Should be 1
COMMIT;
SELECT * FROM t1;
DELETE FROM t1 WHERE s1 >= 1000;
COMMIT;
#
# Verify isolation level with ROLLBACK AND CHAIN
#
connection default;
SET TRANSACTION ISOLATION LEVEL READ COMMITTED;
START TRANSACTION;
connection con1;
START TRANSACTION;
INSERT INTO t1 VALUES (1001);
COMMIT;
connection default;
SELECT COUNT(*) FROM t1 WHERE s1 = 1001;
--echo Should be 1
ROLLBACK AND CHAIN;
connection con1;
INSERT INTO t1 VALUES (1002);
COMMIT;
connection default;
SELECT COUNT(*) FROM t1 WHERE s1 = 1002;
--echo Should be 1
COMMIT;
SELECT * FROM t1;
DELETE FROM t1 WHERE s1 >= 1000;
COMMIT;
#
# Verify isolation level with @completion_type=1.
# (A @@completion_type value of 1 is equivalentl to
# explicitly adding "AND CHAIN" to COMMIT or ROLLBACK)
#
#
# Verify that COMMIT AND NO CHAIN overrides the value
# of @@completion_type
#
SET @@completion_type=1;
connection default;
SET TRANSACTION ISOLATION LEVEL READ COMMITTED;
START TRANSACTION;
connection con1;
START TRANSACTION;
INSERT INTO t1 VALUES (1001);
COMMIT;
connection default;
SELECT * FROM t1 WHERE s1 >= 1000;
--echo Should see 1001
COMMIT AND NO CHAIN;
--echo default transaction is now in REPEATABLE READ
connection con1;
INSERT INTO t1 VALUES (1002);
COMMIT;
connection default;
SELECT * FROM t1 WHERE s1 >= 1000;
--echo Should see 1001 and 1002
connection con1;
INSERT INTO t1 VALUES (1003);
COMMIT;
connection default;
SELECT * FROM t1 WHERE s1 >= 1000;
--echo Should see 1001 and 1002, but NOT 1003
COMMIT;
SELECT * FROM t1;
DELETE FROM t1 WHERE s1 >= 1000;
COMMIT AND NO CHAIN;
SET @@completion_type=0;
COMMIT;
#
# Verify that ROLLBACK AND NO CHAIN overrides the value
# of @@completion_type
#
connection default;
SET @@completion_type=1;
COMMIT AND NO CHAIN;
SET TRANSACTION ISOLATION LEVEL READ COMMITTED;
START TRANSACTION;
connection con1;
START TRANSACTION;
INSERT INTO t1 VALUES (1001);
COMMIT;
connection default;
SELECT * FROM t1 WHERE s1 >= 1000;
--echo Should see 1001
ROLLBACK AND NO CHAIN;
--echo default transaction is now in REPEATABLE READ
connection con1;
INSERT INTO t1 VALUES (1002);
COMMIT;
connection default;
SELECT * FROM t1 WHERE s1 >= 1000;
--echo Should see 1001 and 1002
connection con1;
INSERT INTO t1 VALUES (1003);
COMMIT;
connection default;
SELECT * FROM t1 WHERE s1 >= 1000;
--echo Should see 1001 and 1002, but NOT 1003
COMMIT;
SELECT * FROM t1;
DELETE FROM t1 WHERE s1 >= 1000;
COMMIT AND NO CHAIN;
SET @@completion_type=0;
COMMIT;
#
# Verify that in the sequence:
# SET TRANSACTION ISOLATION LEVEL
# SET SESSION ISOLATION LEVEL
#
# SET SESSION ISOLATION LEVEL has precedence over
# SET TRANSACTION. (Note that this is _not_
# in accordance with ISO 9075.)
#
connection default;
SET TRANSACTION ISOLATION LEVEL READ COMMITTED;
SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ;
START TRANSACTION;
SELECT * FROM t1;
connection con1;
INSERT INTO t1 VALUES (1000);
COMMIT;
connection default;
SELECT * FROM t1;
--echo Should get same result as above (i.e should not read '1000')
COMMIT;
DELETE FROM t1 WHERE s1 >= 1000;
COMMIT;
#
# Verify that a transaction ended with an
# implicit commit (i.e a DDL statement), the
# @@completetion_type setting is ignored, and
# the next transaction's isolation level is
# the session level.
#
SET @@completion_type=1;
COMMIT AND NO CHAIN;
SET TRANSACTION ISOLATION LEVEL READ COMMITTED;
TRUNCATE TABLE t1;
# MDEV-515 takes X-lock on the table for the first insert.
# So concurrent insert won't happen on the table
INSERT INTO t1 VALUES(100);
START TRANSACTION;
INSERT INTO t1 VALUES (1000);
SELECT * FROM t1;
--echo Should read '1000'
connection con1;
INSERT INTO t1 VALUES (1001);
COMMIT;
connection default;
SELECT * FROM t1;
--echo Should only read the '1000' as this transaction is now in REP READ
COMMIT AND NO CHAIN;
SET @@completion_type=0;
COMMIT AND NO CHAIN;
#
# Cleanup
#
SET @@autocommit=1;
COMMIT;
disconnect con1;
DROP TABLE t1;
--echo #
--echo # End of test cases for Bug#20837
--echo #
--echo #
--echo # WL#5968 Implement START TRANSACTION READ (WRITE|ONLY);
--echo #
--echo #
--echo # Test 1: Check supported syntax
START TRANSACTION;
COMMIT;
START TRANSACTION READ ONLY;
COMMIT;
START TRANSACTION READ WRITE;
COMMIT;
--error ER_PARSE_ERROR
START TRANSACTION READ ONLY, READ WRITE;
START TRANSACTION READ ONLY, WITH CONSISTENT SNAPSHOT;
COMMIT;
START TRANSACTION READ WRITE, WITH CONSISTENT SNAPSHOT;
COMMIT;
START TRANSACTION WITH CONSISTENT SNAPSHOT, READ ONLY;
COMMIT;
START TRANSACTION WITH CONSISTENT SNAPSHOT, READ WRITE;
COMMIT;
--error ER_PARSE_ERROR
START TRANSACTION READ ONLY, WITH CONSISTENT SNAPSHOT, READ WRITE;
SET TRANSACTION READ ONLY;
SET TRANSACTION READ WRITE;
SET TRANSACTION ISOLATION LEVEL SERIALIZABLE, READ ONLY;
SET TRANSACTION ISOLATION LEVEL SERIALIZABLE, READ WRITE;
SET TRANSACTION READ ONLY, ISOLATION LEVEL READ COMMITTED;
SET TRANSACTION READ WRITE, ISOLATION LEVEL READ COMMITTED;
--error ER_PARSE_ERROR
SET TRANSACTION READ ONLY, READ WRITE;
COMMIT;
--echo #
--echo # Test 2: Check setting of variable.
SET SESSION TRANSACTION READ WRITE;
SELECT @@tx_read_only;
SET SESSION TRANSACTION READ ONLY;
SELECT @@tx_read_only;
SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ, READ WRITE;
SELECT @@tx_read_only;
SET SESSION TRANSACTION READ ONLY, ISOLATION LEVEL REPEATABLE READ;
SELECT @@tx_read_only;
START TRANSACTION;
--echo # Not allowed inside a transaction
--error ER_CANT_CHANGE_TX_CHARACTERISTICS
SET TRANSACTION READ ONLY;
--echo # But these are allowed.
SET SESSION TRANSACTION READ ONLY;
SET GLOBAL TRANSACTION READ ONLY;
COMMIT;
# Reset to defaults
SET SESSION TRANSACTION READ WRITE;
SET GLOBAL TRANSACTION READ WRITE;
--echo #
--echo # Test 3: Test that write operations are properly blocked.
CREATE TABLE t1(a INT);
CREATE TEMPORARY TABLE temp_t2(a INT);
SET SESSION TRANSACTION READ ONLY;
--echo # 1: DDL should be blocked, also on temporary tables.
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
CREATE TABLE t3(a INT);
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
ALTER TABLE t1 COMMENT "Test";
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
DROP TABLE t1;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
CREATE TEMPORARY TABLE temp_t3(a INT);
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
ALTER TABLE temp_t2 COMMENT "Test";
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
DROP TEMPORARY TABLE temp_t2;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
CREATE FUNCTION f1() RETURNS INT RETURN 1;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
DROP FUNCTION f1;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
CREATE PROCEDURE p1() BEGIN END;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
DROP PROCEDURE p1;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
CREATE VIEW v1 AS SELECT 1;
SET SESSION TRANSACTION READ WRITE;
CREATE VIEW v1 AS SELECT 1;
SET SESSION TRANSACTION READ ONLY;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
DROP VIEW v1;
SET SESSION TRANSACTION READ WRITE;
DROP VIEW v1;
SET SESSION TRANSACTION READ ONLY;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
RENAME TABLE t1 TO t2;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
RENAME TABLE temp_t2 TO temp_t3;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
TRUNCATE TABLE t1;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
CREATE DATABASE db1;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
DROP DATABASE db1;
SET SESSION TRANSACTION READ WRITE;
--echo # 2: DML should be blocked on non-temporary tables.
START TRANSACTION READ ONLY;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
INSERT INTO t1 VALUES (1), (2);
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
UPDATE t1 SET a= 3;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
DELETE FROM t1;
--echo # 3: DML should be allowed on temporary tables.
INSERT INTO temp_t2 VALUES (1), (2);
UPDATE temp_t2 SET a= 3;
DELETE FROM temp_t2;
--echo # 4: Queries should not be blocked.
SELECT * FROM t1;
SELECT * FROM temp_t2;
HANDLER t1 OPEN;
HANDLER t1 READ FIRST;
HANDLER t1 CLOSE;
HANDLER temp_t2 OPEN;
HANDLER temp_t2 READ FIRST;
HANDLER temp_t2 CLOSE;
--echo # 5: Prepared statements
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
PREPARE stmt FROM "DELETE FROM t1";
PREPARE stmt FROM "DELETE FROM temp_t2";
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
COMMIT;
--echo # 6: Stored routines
delimiter |;
CREATE FUNCTION f1() RETURNS INT
BEGIN
DELETE FROM t1;
RETURN 1;
END|
CREATE FUNCTION f2() RETURNS INT
BEGIN
DELETE FROM temp_t2;
RETURN 1;
END|
delimiter ;|
CREATE PROCEDURE p1() DELETE FROM t1;
CREATE PROCEDURE p2() DELETE FROM temp_t2;
START TRANSACTION READ ONLY;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
SELECT f1();
SELECT f2();
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
CALL p1();
CALL p2();
COMMIT;
DROP FUNCTION f1;
DROP FUNCTION f2;
DROP PROCEDURE p1;
DROP PROCEDURE p2;
--echo # 7: Views
CREATE VIEW v1 AS SELECT a FROM t1;
# Not supported for temporary tables.
START TRANSACTION READ ONLY;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
INSERT INTO v1 VALUES (1), (2);
SELECT * FROM v1;
COMMIT;
DROP VIEW v1;
--echo # 8: LOCK TABLE
SET SESSION TRANSACTION READ ONLY;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
LOCK TABLE t1 WRITE;
LOCK TABLE t1 READ;
UNLOCK TABLES;
# Not supported for temporary tables.
SET SESSION TRANSACTION READ WRITE;
DROP TABLE temp_t2, t1;
--echo #
--echo # Test 4: SET TRANSACTION, CHAINing transactions
CREATE TABLE t1(a INT);
SET SESSION TRANSACTION READ ONLY;
START TRANSACTION;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
DELETE FROM t1;
COMMIT;
START TRANSACTION READ WRITE;
DELETE FROM t1;
COMMIT;
SET SESSION TRANSACTION READ WRITE;
SET TRANSACTION READ ONLY;
START TRANSACTION;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
DELETE FROM t1;
COMMIT;
START TRANSACTION READ WRITE;
DELETE FROM t1;
COMMIT;
START TRANSACTION READ ONLY;
SELECT * FROM t1;
COMMIT AND CHAIN;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
DELETE FROM t1;
COMMIT;
START TRANSACTION READ ONLY;
SELECT * FROM t1;
ROLLBACK AND CHAIN;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
DELETE FROM t1;
COMMIT;
DROP TABLE t1;
--echo #
--echo # Test 5: Test that reserved keyword ONLY is still allowed as
--echo # identifier - both directly and in SPs.
SET @only= 1;
CREATE TABLE t1 (only INT);
INSERT INTO t1 (only) values (1);
SELECT only FROM t1 WHERE only = 1;
DROP TABLE t1;
DELIMITER |;
CREATE PROCEDURE p1()
BEGIN
DECLARE only INT DEFAULT 1;
END|
DELIMITER ;|
CALL p1();
DROP PROCEDURE p1;
--echo #
--echo # Test 6: Check that XA transactions obey default access mode.
CREATE TABLE t1(a INT);
SET TRANSACTION READ ONLY;
XA START 'test1';
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
INSERT INTO t1 VALUES (1);
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
UPDATE t1 SET a=2;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
DELETE FROM t1;
XA END 'test1';
XA PREPARE 'test1';
XA COMMIT 'test1';
DROP TABLE t1;
--echo #
--echo # Test 7: SET TRANSACTION inside stored routines
CREATE PROCEDURE p1() SET SESSION TRANSACTION READ ONLY;
CALL p1();
SELECT @@tx_read_only;
SET SESSION TRANSACTION READ WRITE;
DROP PROCEDURE p1;
CREATE PROCEDURE p1() SET SESSION TRANSACTION READ ONLY,
ISOLATION LEVEL SERIALIZABLE;
CALL p1();
SELECT @@tx_read_only;
SET SESSION TRANSACTION READ WRITE, ISOLATION LEVEL REPEATABLE READ;
DROP PROCEDURE p1;
delimiter |;
CREATE FUNCTION f1() RETURNS INT
BEGIN
SET SESSION TRANSACTION READ ONLY;
RETURN 1;
END|
delimiter ;|
SELECT f1();
SELECT @@tx_read_only;
SET SESSION TRANSACTION READ WRITE;
DROP FUNCTION f1;
delimiter |;
CREATE FUNCTION f1() RETURNS INT
BEGIN
SET SESSION TRANSACTION ISOLATION LEVEL SERIALIZABLE, READ ONLY;
RETURN 1;
END|
delimiter ;|
SELECT f1();
SELECT @@tx_read_only;
SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ, READ WRITE;
DROP FUNCTION f1;
--echo #
--echo # Test 8: SET TRANSACTION and auto-commit
SELECT @@autocommit;
CREATE TABLE t1(a INT) engine=InnoDB;
SET TRANSACTION READ ONLY;
SELECT * FROM t1;
--echo # This statement should work, since last statement committed.
INSERT INTO t1 VALUES (1);
DROP TABLE t1;