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BUG#14553: NULL in WHERE resets LAST_INSERT_ID

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To make MySQL compatible with some ODBC applications, you can find
the AUTO_INCREMENT value for the last inserted row with the following query:
 SELECT * FROM tbl_name WHERE auto_col IS NULL.
This is done with a special code that replaces 'auto_col IS NULL' with
'auto_col = LAST_INSERT_ID'.
However this also resets the LAST_INSERT_ID to 0 as it uses it for a flag
so as to ensure that only the first SELECT ... WHERE auto_col IS NULL
after an INSERT has this special behaviour.
In order to avoid resetting the LAST_INSERT_ID a special flag is introduced
in the THD class. This flag is used to restrict the second and subsequent
SELECTs instead of LAST_INSERT_ID.
This commit is contained in:
gkodinov/kgeorge@mysql.com/rakia.(none)
2006-07-10 16:27:03 +03:00
parent ab440799e1
commit 2c9f5cc706
7 changed files with 60 additions and 3 deletions
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3
sql/sql_class.h
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@ -893,6 +893,8 @@ public:
bool last_cuted_field;
bool no_errors, password, is_fatal_error;
bool query_start_used,last_insert_id_used,insert_id_used,rand_used;
/* for IS NULL => = last_insert_id() fix in remove_eq_conds() */
bool substitute_null_with_insert_id;
bool time_zone_used;
bool in_lock_tables;
bool query_error, bootstrap, cleanup_done;
@ -988,6 +990,7 @@ public:
{
last_insert_id= id_arg;
insert_id_used=1;
substitute_null_with_insert_id= TRUE;
}
inline ulonglong insert_id(void)
{