to a single statement.
---
Bug#24795: SHOW PROFILE
Profiling is only partially functional on some architectures. Where
there is no getrusage() system call, presently Null values are
returned where it would be required. Notably, Windows needs some love
applied to make it as useful.
Syntax this adds:
SHOW PROFILES
SHOW PROFILE [types] [FOR QUERY n] [OFFSET n] [LIMIT n]
where "n" is an integer
and "types" is zero or many (comma-separated) of
"CPU"
"MEMORY" (not presently supported)
"BLOCK IO"
"CONTEXT SWITCHES"
"PAGE FAULTS"
"IPC"
"SWAPS"
"SOURCE"
"ALL"
It also adds a session variable (boolean) "profiling", set to "no"
by default, and (integer) profiling_history_size, set to 15 by
default.
This patch abstracts setting THDs' "proc_info" behind a macro that
can be used as a hook into the profiling code when profiling
support is compiled in. All future code in this line should use
that mechanism for setting thd->proc_info.
---
Tests are now set to omit the statistics.
---
Adds an Information_schema table, "profiling" for access to
"show profile" data.
---
Merge zippy.cornsilk.net:/home/cmiller/work/mysql/mysql-5.0-community-3--bug24795
into zippy.cornsilk.net:/home/cmiller/work/mysql/mysql-5.0-community
---
Fix merge problems.
---
Fixed one bug in the query_source being NULL.
Updated test results.
---
Include more thorough profiling tests.
Improve support for prepared statements.
Use session-specific query IDs, starting at zero.
---
Selecting from I_S.profiling is no longer quashed in profiling, as
requested by Giuseppe.
Limit the size of captured query text.
No longer log queries that are zero length.
Fixed compiler warnings (detected by VC++):
- Removed not used variables
- Added casts
- Fixed wrong assignments to bool
- Fixed wrong calls with bool arguments
- Added missing argument to store(longlong), which caused wrong store method to be called.
(Mostly in DBUG_PRINT() and unused arguments)
Fixed bug in query cache when used with traceing (--with-debug)
Fixed memory leak in mysqldump
Removed warnings from mysqltest scripts (replaced -- with #)
When statement to be prepared contained CREATE PROCEDURE, CREATE FUNCTION
or CREATE TRIGGER statements with a syntax error in it, the preparation
would fail with syntax error message, but the memory could be corrupted.
The problem occurred because we switch memroot when parse stored
routine or trigger definitions, and on parse error we restored the
original memroot only after performing some memory operations. In more
detail:
- prepared statement would activate its own memory root to parse
the definition of the stored procedure.
- SP would reset this memory root with its own memory root to
parse SP statements
- a syntax error would happen
- prepared statement would restore the original memory root
- stored procedure would restore what it thinks was the original
memory root, but actually was the statement memory root.
That led to double free - in destruction of the statement and in
a next call to mysql_parse().
The solution is to restore memroot right after the failed parsing.
Do not consider SHOW commands slow queries, just because they don't use proper indexes.
This bug fix is not needed in 5.1, and the code changes will be null merged. However, the test cases will be propogated up to 5.1.
The executing code had a safety assertion so that it refused to free Items
that it didn't create. However, there is a case, undefined user variables,
which would put Items into the list to be freed.
Instead, do something that is more risky in expectation that the code will
be refactored soon, as Kostja wants to do: Remove the assertions from
prepare() and execute(). Put one assertion at a higher level, before
stmt->set_params_from_vars(), which may then create new to-be-freed Items .
- Use the "%.*b" format when printing prepared and exeuted prepared statements to the log.
- Add test case to check that also prepared statements end up in the query log
Bug#14346 Prepared statements corrupting general log/server memory
- Use "stmt->query" when logging the newly prepared query instead of "packet"
dropping/creating tables".
The bug could lead to a crash when multi-delete statements were
prepared and used with temporary tables.
The bug was caused by lack of clean-up of multi-delete tables before
re-execution of a prepared statement. In a statement like
DELETE t1 FROM t1, t2 WHERE ... the first table list (t1) is
moved to lex->auxilliary_table_list and excluded from lex->query_tables
or select_lex->tables. Thus it was unaccessible to reinit_stmt_before_use
and not cleaned up before re-execution of a prepared statement.
A query with a group by and having clauses could return a wrong
result set if the having condition contained a constant conjunct
evaluated to FALSE.
It happened because the pushdown condition for table with
grouping columns lost its constant conjuncts.
Pushdown conditions are always built by the function make_cond_for_table
that ignores constant conjuncts. This is apparently not correct when
constant false conjuncts are present.
supported in SP but not in PS": just enable them in prepared
statements, the supporting functionality was implemented when
they were enabled in stored procedures.
too many open statements". The patch adds a new global variable
@@max_prepared_stmt_count. This variable limits the total number
of prepared statements in the server. The default value of
@@max_prepared_stmt_count is 16382. 16382 small statements
(a select against 3 tables with GROUP, ORDER and LIMIT) consume
100MB of RAM. Once this limit has been reached, the server will
refuse to prepare a new statement and return ER_UNKNOWN_ERROR
(unfortunately, we can't add new errors to 4.1 without breaking 5.0). The limit is changeable after startup
and can accept any value from 0 to 1 million. In case
the new value of the limit is less than the current
statement count, no new statements can be added, while the old
still can be used. Additionally, the current count of prepared
statements is now available through a global read-only variable
@@prepared_stmt_count.
out of a nested join to the on conditions for the nest.
The bug happened due to:
1. The function simplify_joins could change on expressions for nested joins.
Yet modified on expressions were not saved in prep_on_expr.
2. On expressions were not restored for nested joins in
reinit_stmt_before_use.
trigger starts trigger".
In short, the deadlock/crash happened when execution of statement, which used
stored functions or activated triggers, coincided with alteration of the
tables used by these functions or triggers (in highly concurrent environment).
Bug was caused by the incorrect handling of tables from prelocked set in
open_tables() functions in situations when refresh happened. This fix replaces
old smart but not very robust way of handling tables after refresh (which was
closing only old tables), with new one which simply closes all tables opened so
far and restarts open_tables().
Also fixed handling of temporary tables in close_tables_for_reopen().
No test case present since bug manifests itself only in concurrent environment.
A query with a group by and having clauses could return a wrong
result set if the having condition contained a constant conjunct
evaluated to FALSE.
It happened because the pushdown condition for table with
grouping columns lost its constant conjuncts.
Pushdown conditions are always built by the function make_cond_for_table
that ignores constant conjuncts. This is apparently not correct when
constant false conjuncts are present.
Bad examples of usage of a string with its length fixed.
The incorrect length in the trigger file configuration descriptor
fixed (BUG#14090).
A hook for unknown keys added to the parser to support old .TRG files.
