| Bug #36004 | mysql_stmt_prepare resets the list of warnings | ||
|---|---|---|---|
| Submitted: | 11 Apr 21:15 | Modified: | 25 Apr 19:21 |
| Reporter: | Davi Arnaut | ||
| Status: | Closed | ||
| Category: | Server: Errors | Severity: | S3 (Non-critical) |
| Version: | 6.0-BK | OS: | Any |
| Assigned to: | Davi Arnaut | Target Version: | 5.0+ |
| Tags: | show warnings, warning_count, mysql_stmt_prepare | ||
| Triage: | D4 (Minor) | ||
[15 Apr 22:30]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/45455 ChangeSet@1.2642, 2008-04-15 17:29:42-03:00, davi@mysql.com +2 -0 Bug#36004 mysql_stmt_prepare resets the list of warnings Although the manual says that "the list of messages is reset for each new statement that uses a table", the list of messages is being unconditionally reset for prepare commands. The solution is to enforce that the prepare command will only reset the message list if the statement being prepared uses a table or a warning is pushed.
[15 Apr 22:52]
Davi Arnaut
Queued to 6.0-runtime
[20 Apr 15:01]
Bugs System
Pushed into 6.0.6-alpha
[25 Apr 19:21]
Paul DuBois
Noted in 6.0.6 changelog. mysql_stmt_prepare() did not reset the list of messages (those messages available via SHOW WARNINGS).
Description: Although the manual says that "the list of messages is reset for each new statement that uses a table", the list of messages is being reset for COM_STMT_PREPARE (mysql_stmt_prepare) commands. How to repeat: static void test_bug_prepare() { int rc, warning_count= 0; MYSQL_STMT *stmt; const char hello[]= "hello world!"; DBUG_ENTER("test_bug28386"); myheader("test_bug28386"); rc= mysql_query(mysql, "drop table if exists inexistant"); myquery(rc); DIE_UNLESS(mysql_warning_count(mysql) == 1); query_int_variable(mysql, "@@warning_count", &warning_count); DIE_UNLESS(warning_count); stmt= mysql_simple_prepare(mysql, "select 1"); check_stmt(stmt); DIE_UNLESS(mysql_warning_count(mysql) == 0); query_int_variable(mysql, "@@warning_count", &warning_count); DIE_UNLESS(warning_count); rc= mysql_stmt_execute(stmt); check_execute(stmt, rc); DIE_UNLESS(mysql_warning_count(mysql) == 0); query_int_variable(mysql, "@@warning_count", &warning_count); DIE_UNLESS(warning_count); mysql_stmt_close(stmt); DBUG_VOID_RETURN; } Suggested fix: Instead of remove all warnings, the stmt prepare command should only reset the list of warnings if the statement being prepared uses a table. The fix should be something similar to what we already have in mysql_execute_command: /* Reset warning count for each query that uses tables A better approach would be to reset this for any commands that is not a SHOW command or a select that only access local variables, but for now this is probably good enough. Don't reset warnings when executing a stored routine. */ if ((all_tables || !lex->is_single_level_stmt()) && !thd->spcont) mysql_reset_errors(thd, 0);