mirror/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2026-05-02 13:15:32 +02:00
Code Issues Projects Releases Packages Wiki Activity

Fix bug#14186 select datefield is null not updated

Browse source 
Date field was declared as not null, thus expression 'datefield is null'
was always false. For SELECT special handling of such cases is used. 
There 'datefield is null' converted to 'datefield eq "0000-00-00"'.

In mysql_update() before creation of select added remove_eq_conds() call.
It makes some optimization of conds and in particular performs conversion
from 'is null' to 'eq'. 
Also remove_eq_conds() makes some evaluation of conds and if it founds that
conds is always false then update statement is not processed further.
All this allows to perform some update statements process faster due to
optimized conds, and not wasting resources if conds known to be false. 


sql/sql_select.cc:
  Fix bug#14186  select datefield is null not updated
  Remove static from remove_eq_conds()
sql/sql_select.h:
   Fix bug#14186  select datefield is null not updated
  Added remove_eq_conds() prototype.
mysql-test/r/update.result:
  Test case for  bug#14186  select datefield is null not updated
mysql-test/t/update.test:
  Test case for  bug#14186  select datefield is null not updated
sql/sql_update.cc:
  Fix bug#14186  select datefield is null not updated
  To mysql_update() added call to remove_eq_conds() to optimize conds and convert 'datefield is null' to 'datefield eq 0000-00-00'
This commit is contained in:
unknown 2005-10-28 01:24:11 +04:00
commit 6020281e95
5 changed files with 31 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

9
mysql-test/t/update.test
View file

@ -260,5 +260,14 @@ update t1 set a=a+11,b=2 order by a limit 3;
update t1 set a=a+12,b=3 order by a limit 3;
select * from t1 order by a;
drop table t1;
#
# Bug#14186 select datefield is null not updated
#
create table t1 (f1 date not null);
insert into t1 values('2000-01-01'),('0000-00-00');
update t1 set f1='2002-02-02' where f1 is null;
select * from t1;
drop table t1;
# End of 4.1 tests