Commit 01c9fd31 authored by unknown's avatar unknown
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Bug #20195: INSERT DELAYED with auto_increment is assigned wrong values 

The INSERT DELAYED should not maintain its own private auto-increment
counter, because this is assuming that other threads cannot insert
into the table while the INSERT DELAYED thread is inserting, which is
a wrong assumption.

So the start of processing of a batch of INSERT rows in the 
INSERT DELAYED thread must be treated as a start of a new statement
and cached next_insert_id must be cleared.


mysql-test/r/delayed.result:
  test suite for the bug
mysql-test/t/delayed.test:
  test suite for the bug
sql/sql_insert.cc:
  Reset auto-increment cacheing before processing
  the next batch of inserts in the handler thread
parent 64742194

mysql-test/r/delayed.result

+30 −0
Original line number Diff line number Diff line
@@ -39,3 +39,33 @@ select * from t1; 
a

1

drop table t1;

CREATE TABLE t1 ( a int(10) NOT NULL auto_increment, PRIMARY KEY (a));

insert delayed into t1 values(null);

insert into t1 values(null);

insert into t1 values(null);

insert delayed into t1 values(null);

insert delayed into t1 values(null);

insert delayed into t1 values(null);

insert into t1 values(null);

insert into t1 values(null);

insert into t1 values(null);

delete from t1 where a=6;

insert delayed into t1 values(null);

insert delayed into t1 values(null);

insert delayed into t1 values(null);

insert delayed into t1 values(null);

select * from t1 order by a;

a

1

2

3

4

5

7

8

9

10

11

12

13

DROP TABLE t1;

mysql-test/t/delayed.test

+49 −0
Original line number Diff line number Diff line
@@ -50,3 +50,52 @@ insert into t1 values (1); 
insert delayed into t1 values (1);

select * from t1;

drop table t1;



#

# Bug #20195: INSERT DELAYED with auto_increment is assigned wrong values

#

CREATE TABLE t1 ( a int(10) NOT NULL auto_increment, PRIMARY KEY (a));



# Make one delayed insert to start the separate thread

insert delayed into t1 values(null);



# Do some normal inserts

insert into t1 values(null);

insert into t1 values(null);



# Discarded, since the delayed-counter is 2, which is already used

insert delayed into t1 values(null);



# Discarded, since the delayed-counter is 3, which is already used

insert delayed into t1 values(null);



# Works, since the delayed-counter is 4, which is unused

insert delayed into t1 values(null);



# Do some more inserts

insert into t1 values(null);

insert into t1 values(null);

insert into t1 values(null);



# Delete one of the above to make a hole

delete from t1 where a=6;



# Discarded, since the delayed-counter is 5, which is already used

insert delayed into t1 values(null);



# Works, since the delayed-counter is 6, which is unused (the row we deleted)

insert delayed into t1 values(null);



# Discarded, since the delayed-counter is 7, which is already used

insert delayed into t1 values(null);



# Works, since the delayed-counter is 8, which is unused

insert delayed into t1 values(null);



# Check what we have now

# must wait so that the delayed thread finishes

# Note: this must be increased if the test fails

--sleep 1

select * from t1 order by a;



DROP TABLE t1;

sql/sql_insert.cc

+8 −0
Original line number Diff line number Diff line
@@ -1938,6 +1938,14 @@ bool delayed_insert::handle_inserts(void) 
  if (!using_bin_log)

    table->file->extra(HA_EXTRA_WRITE_CACHE);

  pthread_mutex_lock(&mutex);



  /* Reset auto-increment cacheing */

  if (thd.clear_next_insert_id)

  {

    thd.next_insert_id= 0;

    thd.clear_next_insert_id= 0;

  }



  while ((row=rows.get()))

  {

    stacked_inserts--;