expression cols.
The problem was that MYSQL_FIELD::org_name was set for MIN() and MAX()
functions (COUNT() is also mentioned in the bug report but was already
fixed).
After this patch for expressions MYSQL_FIELD::name is set to either
expression itself or its alias, and other data origin fields of
MYSQL_FILED (db, org_table, table, org_name) are empty strings.
sql/item_sum.cc:
For expressions only col_name should be non-empty string.
tests/mysql_client_test.c:
Add test case for bug#21635: MYSQL_FIELD struct's member strings seem
to misbehave for expression cols.
into mysql.com:/usr/home/ram/work/bug22029/my41-bug22029
mysql-test/r/date_formats.result:
Auto merged
mysql-test/t/date_formats.test:
Auto merged
sql/item_timefunc.cc:
Auto merged
into mysql.com:/usr/home/ram/work/bug22029/my50-bug22029
mysql-test/r/date_formats.result:
Auto merged
mysql-test/t/date_formats.test:
Auto merged
sql/item_timefunc.cc:
Auto merged
into mysql.com:/usr/home/ram/work/bug22029/my50-bug22029
mysql-test/r/date_formats.result:
Auto merged
mysql-test/t/date_formats.test:
Auto merged
sql/item_timefunc.cc:
merging
Make Prepared_stmt_count a global status variable, accessible via
SHOW STATUS LIKE 'Prepared_stmt_count';. Documentation should be
updated.
mysql-test/r/ps.result:
Update result for bug#16365: Prepared Statements: DoS with too many
open statements, according to bug#23159: prepared_stmt_count should be
status variable.
mysql-test/t/ps.test:
Update test case for bug#16365: Prepared Statements: DoS with too many
open statements, according to bug#23159: prepared_stmt_count should be
status variable.
sql/mysqld.cc:
Add Prepared_stmt_count as global status variable.
sql/set_var.cc:
Remove prepared_stmt_count as system variable.
disable filling of I_S tables for EXPLAIN
mysql-test/r/information_schema.result:
Bug#22413 EXPLAIN SELECT FROM view with ORDER BY yield server crash
test case
mysql-test/t/information_schema.test:
Bug#22413 EXPLAIN SELECT FROM view with ORDER BY yield server crash
test case
into mysql.com:/home/my/mysql-5.0
mysql-test/t/ctype_ucs.test:
Auto merged
sql/log_event.cc:
Auto merged
sql/slave.cc:
Auto merged
sql/sql_parse.cc:
Auto merged
sql/sql_repl.cc:
Auto merged
sql/sql_select.cc:
Auto merged
Do not issue a 'read-only' error in case of DROP TEMPORARY TABLE on a non-existing temporary table.
Instead produce the correct "Unknown table" error or warning (in cases when the IF EXISTS clause was specified).
To a documentor: the part of the manual describing the 'read_only' system variable should be clarified to state the following:
"When the read_only variable is set to ON, all operations which create/update/drop tables are rejected with the exceptions for:
1. Any operation performed by the replication thread on a slave server
2. Any operation performed by a user that have the SUPER privilege
3. Any operation that creates/updates/drops only temporary tables"
mysql-test/r/read_only.result:
Added testcases for bug #22077 "DROP TEMPORARY TABLE fails with wrong error if read_only is set"
mysql-test/t/read_only.test:
Added testcases for bug #22077 "DROP TEMPORARY TABLE fails with wrong error if read_only is set"
sql/sql_parse.cc:
Before issuing the 'read-only' error also check if the operation is not a DROP TEMPORARY TABLE statement
limitation)
Note to the reviewer
====================
Warning: reviewing this patch is somewhat involved.
Due to the nature of several issues all affecting the same area,
fixing separately each issue is not practical, since each fix can not be
implemented and tested independently.
In particular, the issues with
- rule recursion
- nested case statements
- forward jump resolution (backpatch list)
are tightly coupled (see below).
Definitions
===========
The expression
CASE expr
WHEN expr THEN expr
WHEN expr THEN expr
...
END
is a "Simple Case Expression".
The expression
CASE
WHEN expr THEN expr
WHEN expr THEN expr
...
END
is a "Searched Case Expression".
The statement
CASE expr
WHEN expr THEN stmts
WHEN expr THEN stmts
...
END CASE
is a "Simple Case Statement".
The statement
CASE
WHEN expr THEN stmts
WHEN expr THEN stmts
...
END CASE
is a "Searched Case Statement".
A "Left Recursive" rule is like
list:
element
| list element
;
A "Right Recursive" rule is like
list:
element
| element list
;
Left and right recursion produces the same language, the difference only
affects the *order* in which the text is parsed.
In a descendant parser (usually written manually), right recursion works
very well, and is typically implemented with a while loop.
In an ascendant parser (yacc/bison) left recursion works very well,
and is implemented naturally by the parser stack.
In both cases, using the wrong type or recursion is very bad and should be
avoided, as it causes technical issues with the parser implementation.
Before this change
==================
The "Simple Case Expression" and "Searched Case Expression" were both
implemented by the "when_list" and "when_list2" rules, which are left
recursive (ok).
These rules, however, used lex->when_list instead of using the parser stack,
which is more complex that necessary, and potentially dangerous because
of other rules using THD::reset_lex.
The "Simple Case Statement" and "Searched Case Statements" were implemented
by the "sp_case", "sp_whens" and in part by "sp_proc_stmt" rules.
Both cases were right recursive (bad).
The grammar involved was convoluted, and is assumed to be the results of
tweaks to get the code generation to work, but is not what someone would
naturally write.
In addition, using a common rule for both "Simple" and "Searched" case
statements was implemented with sp_head::m_flags |= IN_SIMPLE_CASE,
which is a flag and not a stack, and therefore does not take into account
*nested* case statements. This leads to incorrect generated code, and either
a server crash or an incorrect result.
With regards to the backpatch mechanism, a *different* backpatch list was
created for each jump from "WHEN expr THEN stmt" to "END CASE", which
relied on the grammar to be right recursive.
This is a mis-use of the backpatch list, since this list can resolve
multiple references to the same target at once.
The optimizer algorithm used to detect dead code in the "assembly" SQL
instructions, implemented by sp_head::opt_mark(uint ip), was recursive
in some cases (a conditional jump pointing forward to another conditional
jump).
In case of specially crafted code, like
- a long list of "IF expr THEN stmt END IF"
- a long CASE statement
this would actually cause a server crash with a stack overflow.
In general, having a stack that grows proportionally with user data (the
SQL code given by the client in a CREATE PROCEDURE) is to be avoided.
In debug builds only, creating a SP / SF / Trigger which had a significant
amount of code would spend --literally-- several minutes in sp_head::create,
because of the debug code involved with DBUG_PRINT("info", ("Code %s ...
There are several issues with this code:
- in a CASE with 5 000 WHEN, there are 15 000 instructions generated,
which create a sting representation of the code which is 500 000 bytes
long,
- using a String instead of an io stream causes performances to degrade
to a total server freeze, as time is spent doing realloc of a buffer
always too short,
- Printing a 500 000 long string in the debug log is too verbose,
- Generating this string even when DBUG_PRINT is off is useless,
- Having code that potentially can affect the server behavior, used with
#ifdef / #endif is useful in some cases, but is also a bad practice.
After this change
=================
"Case Expressions" (both simple and searched) have been simplified to
not use LEX::when_list, which has been removed.
Considering all the issues affecting case statements, the grammar for these
has been totally re written.
The existing actions, used to generate "assembly" sp_inst* code, have been
preserved but moved in the new grammar, with the following changes:
a) Bison rules are no longer shared between "Simple" and "Searched" case
statements, because a stack instead of a flag is required to handle them.
Nested statements are handled naturally by the parser stack, which by
definition uses the correct rule in the correct context.
Nested statements of the opposite type (simple vs searched) works correctly.
The flag sp_head::IN_SIMPLE_CASE is no longer used.
This is a step towards resolution of WL#2999, which correctly identified
that temporary parsing flags do not belong to sp_head.
The code in the action is shared by mean of the case_stmt_action_xxx()
helpers.
b) The backpatch mechanism, used to resolve forward jumps in the generated
code, has been changed to:
- create a label for the instruction following 'END CASE',
- register each jump at the end of a "WHEN expr THEN stmt" in a *unique*
backpatch list associated with the 'END CASE' label
- resolve all the forward jumps for this label at once.
In addition, the code involving backpatch has been commented, so that a
reader can now understand by reading matching "Registering" and "Resolving"
comments how the forward jumps are resolved and what target they resolve to,
as this is far from evident when reading the code alone.
The implementation of sp_head::opt_mark() has been revised to avoid
recursive calls from jump instructions, and instead add the jump location
to the list of paths to explore during the flow analysis of the instruction
graph, with a call to sp_head::add_mark_lead().
In addition, the flow analysis will stop if an instruction has already
been marked as reachable, which the previous code failed to do in the
recursive case.
sp_head::opt_mark() is now private, to prevent new calls to this method from
being introduced.
The debug code present in sp_head::create() has been removed.
Considering that SHOW PROCEDURE CODE is also available in debug builds,
and can be used anytime regardless of the trace level, as opposed to
"CREATE PROCEDURE" time and only if the trace was on,
removing the code actually makes debugging easier (usable trace).
Tests have been written to cover the parser overflow (big CASE),
and to cover nested CASE statements.
mysql-test/r/sp-code.result:
Test cases for nested CASE statements.
mysql-test/t/sp-code.test:
Test cases for nested CASE statements.
sql/sp_head.cc:
Re factored opt_mark() to avoid recursion, clean up.
sql/sp_head.h:
Re factored opt_mark() to avoid recursion, clean up.
sql/sql_lex.cc:
Removed when_list.
sql/sql_lex.h:
Removed when_list.
sql/sql_yacc.yy:
Minor clean up for case expressions,
Major re write for case statements (Bug#19194).
mysql-test/r/sp_stress_case.result:
New test for massive CASE statements.
mysql-test/t/sp_stress_case.sh:
New test for massive CASE statements.
mysql-test/t/sp_stress_case.test:
New test for massive CASE statements.
into mysql.com:/home/hf/work/mysql-5.0-0mrg
BitKeeper/deleted/.del-mysql_client.test:
Auto merged
include/mysql.h:
Auto merged
libmysqld/lib_sql.cc:
Auto merged
mysql-test/r/order_by.result:
Auto merged
mysql-test/r/query_cache.result:
Auto merged
mysql-test/r/subselect.result:
Auto merged
mysql-test/r/type_newdecimal.result:
Auto merged
mysql-test/t/flush.test:
Auto merged
mysql-test/t/flush_block_commit.test:
Auto merged
mysql-test/t/innodb-deadlock.test:
Auto merged
mysql-test/t/innodb-lock.test:
Auto merged
mysql-test/t/lock_multi.test:
Auto merged
mysql-test/t/mysql.test:
Auto merged
mysql-test/t/query_cache.test:
Auto merged
mysql-test/t/rename.test:
Auto merged
mysql-test/t/show_check.test:
Auto merged
mysql-test/t/status.test:
Auto merged
mysql-test/t/subselect.test:
Auto merged
mysql-test/t/type_newdecimal.test:
Auto merged
sql/field.cc:
Auto merged
sql/field.h:
Auto merged
sql/handler.cc:
Auto merged
sql/item.cc:
Auto merged
sql/item.h:
Auto merged
sql/item_func.cc:
Auto merged
sql/item_func.h:
Auto merged
sql/item_subselect.cc:
Auto merged
sql/item_subselect.h:
Auto merged
sql/item_sum.cc:
Auto merged
sql/item_sum.h:
Auto merged
sql/item_timefunc.cc:
Auto merged
sql/item_timefunc.h:
Auto merged
sql/mysql_priv.h:
Auto merged
sql/protocol.cc:
Auto merged
sql/protocol.h:
Auto merged
sql/sql_base.cc:
Auto merged
sql/sql_class.h:
Auto merged
sql/sql_lex.cc:
Auto merged
sql/sql_lex.h:
Auto merged
sql/sql_parse.cc:
Auto merged
sql/sql_select.cc:
Auto merged
sql/sql_show.cc:
Auto merged
sql/sql_table.cc:
Auto merged
sql/sql_yacc.yy:
Auto merged
sql/table.cc:
Auto merged
sql-common/client.c:
Auto merged
sql-common/my_time.c:
Auto merged
Makefile.am:
merging
client/mysqltest.c:
merging
include/my_time.h:
merging
libmysql/libmysql.c:
merging
mysql-test/t/order_by.test:
merging
sql/sql_cache.cc:
Call of BLOCK_UNLOCK_WR() moved before query_cache.check_integrity() call which privent lock of query cache during debugging.
Comments added.
into mysql.com:/home/hf/work/mysql-4.1-mrg
include/mysql.h:
Auto merged
mysql-test/r/subselect.result:
Auto merged
mysql-test/t/rename.test:
Auto merged
mysql-test/t/subselect.test:
Auto merged
sql-common/client.c:
Auto merged
sql/sql_class.h:
Auto merged
Makefile.am:
merging
client/mysqltest.c:
merging
mysql-test/t/mysql_client.test:
merging
(this is the 5.0 patch, because 4.1 differs)
There was an improper order of doing chained operations.
To the documentor: ENABLE|DISABLE KEYS combined with RENAME TO, and no other
ALTER TABLE clause, leads to server crash independent of the presence of
indices and data in the table.
mysql-test/r/alter_table.result:
post-merge fix
my locale is utf8, and this breaks non-utf8 stuff when doing manual merge :(
sql/sql_table.cc:
If there is operation on the KEYS, first do it
and then do a rename if there is such. Or, we will crash because
the underlying table has changed.
There was an improper order of doing chained operations.
To the documentor: ENABLE|DISABLE KEYS combined with RENAME TO, and no other
ALTER TABLE clause, leads to server crash independent of the presence of
indices and data in the table.
mysql-test/r/alter_table.result:
update result
mysql-test/t/alter_table.test:
add test for bug#24129
sql/sql_table.cc:
If there is operation on the KEYS, first do it
and then do a rename if there is such. Or, we will crash because
the underlying table has changed.
into mysql.com:/usr/home/ram/work/bug23653/my50-bug23653
mysql-test/r/func_time.result:
Auto merged
mysql-test/t/func_time.test:
Auto merged
sql/item_timefunc.cc:
Auto merged
mysql-test/r/func_str.result:
Add result for bug#17047: CHAR() and IN() can return NULL without
signaling NULL result.
mysql-test/t/func_str.test:
Add test case for bug#17047: CHAR() and IN() can return NULL without
signaling NULL result.
sql/item_strfunc.cc:
Add Item_str_func::fix_fields() implementation, and set maybe_null to
TRUE if we are in the SQL mode that requires some functions to return
null even if they normally do not.
sql/item_strfunc.h:
Add declaration of Item_str_func::fix_fields().
Do not reset maybe_null in Item_func_char::fix_length_and_dec().
The problem was that some functions (namely IN() starting with 4.1, and
CHAR() starting with 5.0) were returning NULL in certain conditions,
while they didn't set their maybe_null flag. Because of that there could
be some problems with 'IS NULL' check, and statements that depend on the
function value domain, like CREATE TABLE t1 SELECT 1 IN (2, NULL);.
The fix is to set maybe_null correctly.
mysql-test/r/func_in.result:
Add result for bug#17047: CHAR() and IN() can return NULL without
signaling NULL result.
mysql-test/t/func_in.test:
Add test case for bug#17047: CHAR() and IN() can return NULL without
signaling NULL result.
sql/item_cmpfunc.cc:
Remove assignment to maybe_null, as it was already set in fix_fields()
based on all arguments, not only on the first.
- Added 'SET NAMES <charset>" upon ::open
- Added test and results for simple UTF test
federated.test:
BUG #17044 Federated Storage Engine not UTF8 clean
New test. Using hex - pasting various charsets in the terminal doesn't work.
federated.result:
BUG# 17044 Federated Storage Engine not UTF8 clean
New test results
ha_federated.cc:
BUG# 17044 Federated Storage Engine not UTF8 clean
Upon ::open, set names to table's charset
sql/ha_federated.cc:
BUG# 17044 Federated Storage Engine not UTF8 clean
Upon ::open, set names to table's charset
mysql-test/t/federated.test:
BUG #17044 Federated Storage Engine not UTF8 clean
New test. Using hex - pasting various charsets in the terminal doesn't work.
federated.result:
BUG# 17044 Federated Storage Engine not UTF8 clean
New test results
mysql-test/r/federated.result:
BUG# 17044 Federated Storage Engine not UTF8 clean
New test results
Problem: When we have a really large number (between 2^63 and 2^64)
as the left side of the mod operator, it gets improperly corerced
into a signed value.
Solution: Added check to see if the "negative" number is really
positive, and if so, cast it.
mysql-test/r/bigint.result:
Added test case result
mysql-test/t/bigint.test:
Added test case
sql/item_func.cc:
Added check to see if we have an unsigned number that looks like a
signed number.
The problem was that THD::row_count_func was zeroed too. It was zeroed
as a fix for bug 4905 "Stored procedure doesn't clear for "Rows affected"
However, the proper solution is not to zero, because THD::row_count_func has
been set to -1 already in mysql_execute_command(), a later fix, which obsoletes
the incorrect fix of #4095
mysql-test/r/sp.result:
update result
mysql-test/t/sp.test:
test for bug#23760 ROW_COUNT() and store procedure not owrking together
sql/sql_parse.cc:
Remove zeroing for thd->row_count_func
The fix for #4905 wasn't right. Now, it's ok without this zeroing
because if there was an error THD::
The regression is caused by the fix for bug 14767. When INSERT ... SELECT
used a view in the SELECT list that was not inlined, and there was an
active transaction, the server could crash in Query_cache::invalidate.
On INSERT ... SELECT only the table being inserted into is invalidated.
Thus views that can't be inlined are skipped from invalidation.
The bug manifests itself in two ways so there is 2 test cases.
One checks that the only the table being inserted into is invalidated.
And the second one checks that there is no crash on INSERT ... SELECT.
mysql-test/t/query_cache.test:
Added a test case for bug#20045: Server crash on INSERT ... SELECT ... FROM non-mergeable view
mysql-test/r/query_cache.result:
Added a test case for bug#20045: Server crash on INSERT ... SELECT ... FROM non-mergeable view
sql/sql_parse.cc:
Bug#20045: Server crash on INSERT ... SELECT ... FROM non-mergeable view
On INSERT ... SELECT only the table being inserted into is invalidated.
ver 5.0 and 5.1 refinement.
adding to the MAX_SIZE_LOG_EVENT_STATUS estimation status vars and
EXECUTE_LOAD_QUERY_EXTRA_HEADER_LEN
sql/log_event.cc:
assertion on size of status vars
sql/log_event.h:
MAX_SIZE_LOG_EVENT_STATUS as the max bytes of contribution of status vars into repl
message; MAX_SIZE_LOG_EVENT_STATUS is getting more wrt to 4.1 version.
This change set implements the DROP TRIGGER IF EXISTS functionality.
This fix is considered a bug and not a feature, because without it,
there is no known method to write a database creation script that can create
a trigger without failing, when executed on a database that may or may not
contain already a trigger of the same name.
Implementing this functionality closes an orthogonality gap between triggers
and stored procedures / stored functions (which do support the DROP IF
EXISTS syntax).
In sql_trigger.cc, in mysql_create_or_drop_trigger,
the code has been reordered to:
- perform the tests that do not depend on the file system (access()),
- get the locks (wait_if_global_read_lock, LOCK_open)
- call access()
- perform the operation
- write to the binlog
- unlock (LOCK_open, start_waiting_global_read_lock)
This is to ensure that all the code that depends on the presence of the
trigger file is executed in the same critical section,
and prevents race conditions similar to the case fixed by Bug 14262 :
- thread 1 executes DROP TRIGGER IF EXISTS, access() returns a failure
- thread 2 executes CREATE TRIGGER
- thread 2 logs CREATE TRIGGER
- thread 1 logs DROP TRIGGER IF EXISTS
The patch itself is based on code contributed by the MySQL community,
under the terms of the Contributor License Agreement (See Bug 18161).
mysql-test/r/rpl_trigger.result:
DROP TRIGGER IF EXISTS
mysql-test/r/trigger.result:
DROP TRIGGER IF EXISTS
mysql-test/t/rpl_trigger.test:
DROP TRIGGER IF EXISTS
mysql-test/t/trigger.test:
DROP TRIGGER IF EXISTS
sql/sql_trigger.cc:
DROP TRIGGER IF EXISTS
sql/sql_yacc.yy:
DROP TRIGGER IF EXISTS
The code that set up data to be passed to user-defined functions was very
old and analyzed the "Type" of the data that was passed into the UDF, when
it really should analyze the "return_type", which is hard-coded for simple
Items and works correctly for complex ones like functions.
---
Added test at Sergei's behest.
mysql-test/r/udf.result:
Verify that various arguments work.
---
Added test at Sergei's behest.
mysql-test/t/udf.test:
Verify that various arguments work.
---
Added test at Sergei's behest.
sql/item_func.cc:
For function-Items, test whether it is constant and set the struct members
for the UDF parameter appropriately.
Replace tabs with spaces in affected code.
sql/udf_example.c:
Include a simple function that is useful in testing.
into mysql.com:/home/bk/MERGE/mysql-5.0-merge
BitKeeper/triggers/post-commit:
Auto merged
mysql-test/t/func_gconcat.test:
Auto merged
sql/item_sum.cc:
Auto merged
sql/sql_repl.cc:
Auto merged
sql/log_event.h:
Manual merge
sql/slave.cc:
Manual merge
