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Bug #27417 thd->no_trans_update.stmt lost value inside of SF-exec-stack
  
Once had been set the flag might later got reset inside of a stored routine 
execution stack.
The reason was in that there was no check if a new statement started at time 
of resetting.
The artifact affects most of binlogable DML queries. Notice, that multi-update 
is wrapped up within
  bug@27716 fix, multi-delete bug@29136.
  
Fixed with saving parent's statement flag of whether the statement modified 
non-transactional table, and unioning (merging) the value with that was gained 
in mysql_execute_command.
  
Resettling thd->no_trans_update members into thd->transaction.`member`;
Asserting code;
Effectively the following properties are held.
  
1. At the end of a substatement thd->transaction.stmt.modified_non_trans_table
   reflects the fact if such a table got modified by the substatement.
   That also respects THD::really_abort_on_warnin() requirements.
2. Eventually thd->transaction.stmt.modified_non_trans_table will be computed as
   the union of the values of all invoked sub-statements.
   That fixes this bug#27417;

Computing of thd->transaction.all.modified_non_trans_table is refined to base to 
the stmt's value for all the case including insert .. select statement which 
before the patch had an extra issue bug@28960.
Minor issues are covered with mysql_load, mysql_delete, and binloggin of insert in
to temp_table select. 
  
The supplied test verifies limitely, mostly asserts. The ultimate testing is defered
for bug@13270, bug@23333.
This commit is contained in:
gkodinov/kgeorge@magare.gmz
2007-07-30 18:27:36 +03:00
parent b6bb988d12
commit 9a0e6ec6d2
16 changed files with 368 additions and 90 deletions
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29
sql/handler.h
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@@ -420,6 +420,35 @@ typedef struct st_thd_trans
bool no_2pc;
/* storage engines that registered themselves for this transaction */
handlerton *ht[MAX_HA];
/*
The purpose of this flag is to keep track of non-transactional
tables that were modified in scope of:
- transaction, when the variable is a member of
THD::transaction.all
- top-level statement or sub-statement, when the variable is a
member of THD::transaction.stmt
This member has the following life cycle:
* stmt.modified_non_trans_table is used to keep track of
modified non-transactional tables of top-level statements. At
the end of the previous statement and at the beginning of the session,
it is reset to FALSE. If such functions
as mysql_insert, mysql_update, mysql_delete etc modify a
non-transactional table, they set this flag to TRUE. At the
end of the statement, the value of stmt.modified_non_trans_table
is merged with all.modified_non_trans_table and gets reset.
* all.modified_non_trans_table is reset at the end of transaction
* Since we do not have a dedicated context for execution of a
sub-statement, to keep track of non-transactional changes in a
sub-statement, we re-use stmt.modified_non_trans_table.
At entrance into a sub-statement, a copy of the value of
stmt.modified_non_trans_table (containing the changes of the
outer statement) is saved on stack. Then
stmt.modified_non_trans_table is reset to FALSE and the
substatement is executed. Then the new value is merged with the
saved value.
*/
bool modified_non_trans_table;
} THD_TRANS;
enum enum_tx_isolation { ISO_READ_UNCOMMITTED, ISO_READ_COMMITTED,