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We now allow multitable queries with order by and limit, such as: delete t1.*, t2.* from t1, t2 order by t1.id desc limit 3; To predict what rows will be deleted, run the equivalent select: select t1.*, t2.* from t1, t2 order by t1.id desc limit 3; Additionally, index hints are now supported with single table delete statements: delete from t2 use index(xid) order by (id) limit 2; This approach changes the multi_delete SELECT result interceptor to use a temporary table to collect row ids pertaining to the rows that will be deleted, rather than directly deleting rows from the target table(s). Row ids are collected during send_data, then read during send_eof to delete target rows. In the event that the temporary table created in memory is not big enough for all matching rows, it is converted to an aria table. Other changes: - Deleting from a sequence now affects zero rows instead of emitting an error Limitations: - The federated connector does not create implicit row ids, so we to use a key when conditionally deleting. See the change in federated_maybe_16324629.test
23 lines
570 B
Text
23 lines
570 B
Text
#
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# Inspired by a bug fix for internal Oracle MySQL bug#16324629
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#
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source include/federated.inc;
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connection slave;
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create table federated.t1 (a int, b int, unique key (a), key (b));
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connection master;
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--replace_result $SLAVE_MYPORT SLAVE_PORT
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eval create table t1 (a int, b int, unique key (a), key (b))
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engine=federated CONNECTION='mysql://root@127.0.0.1:$SLAVE_MYPORT/federated/t1';
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insert into t1 values (3, 3), (7, 7);
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delete t1 from t1 where b = 3;
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select * from t1;
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drop table t1;
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connection slave;
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connection default;
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source include/federated_cleanup.inc;
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