comments)

This change set is for 5.1 (manually merged)

Before this fix, the server would accept queries that contained comments,
even when the comments were not properly closed with a '*' '/' marker.

For example,
  select 1 /* + 2 <EOF>
would be accepted as
  select 1 /* + 2 */ <EOF>
and executed as
  select 1

With this fix, the server now rejects queries with unclosed comments
as syntax errors.
Both regular comments ('/' '*') and special comments ('/' '*' '!') must be
closed with '*' '/' to be parsed correctly.


mysql-test/r/comments.result:
  Unbalanced comments are a syntax error.
mysql-test/t/comments.test:
  Unbalanced comments are a syntax error.
sql/sql_lex.cc:
  Unbalanced comments are a syntax error.

into  weblab.(none):/home/marcsql/TREE/mysql-5.1-rt50-merge


mysql-test/r/comments.result:
  failed auto merge
mysql-test/t/comments.test:
  failed auto merge
sql/sql_lex.cc:
  failed auto merge

into  weblab.(none):/home/marcsql/TREE/mysql-5.0-28779-b

PREPARE and EXECUTE of statement breaks binlog.


sql/sp.cc:
  - Polishing sp_use_new_db():
    - renamed no_access_check to force_switch to be more adequate;
    - fixed comment;
sql/sql_class.h:
  Polishing: fixed comment.
sql/sql_db.cc:
  1. Use mysql_change_db_impl() to reset current database instead of
  THD::set_db() in mysql_rm_db(). THD::set_db() does not take care of
  THD::db_access and database attributes (@@collation_database).
  2. Polishing: add, fix comments.

into  polly.(none):/home/kaa/src/bug30164/my51-bug30164


mysql-test/t/mysql.test:
  Auto merged

Use double quotes instead of single ones which make the test fail on Windows. This is for bug #30164.


mysql-test/t/mysql.test:
  Use double quotes instead of single ones which make the test fail on Windows.

into  polly.(none):/home/kaa/src/bug30164/my51-bug30164


client/mysql.cc:
  Auto merged
mysql-test/r/mysql.result:
  Auto merged
mysql-test/t/mysql.test:
  Auto merged

  
Problem:
  
In cases when a client-side macro appears inside a server-side comment, the add_line() function in mysql.cc discarded all characters until the next delimiter to remove macro arguments from the query string. This resulted in broken queries being sent to the server when the next delimiter character appeared past the comment's boundaries, because the comment closing sequence ('*/') was discarded.
  
Fix:
  
If a client-side macro appears inside a server-side comment, discard all characters in the comment after the macro (that is, until the end of the comment rather than the next delimiter).
This is a minimal fix to allow only simple cases used by the mysqlbinlog utility. Limitations that are worth documenting:
  
- Nested server-side and/or client-side comments are not supported by mysql.cc
- Using client-side macros in multi-line server-side comments is not supported
- All characters after a client-side macro in a server-side comment will be omitted from the query string (and thus, will not be sent to server).


client/mysql.cc:
  If a client-side macro appears inside a server-side comment, discard all characters in the comment after the macro.
mysql-test/r/mysql.result:
  Added a test case for bug #30164.
mysql-test/t/mysql.test:
  Added a test case for bug #30164.

into  weblab.(none):/home/marcsql/TREE/mysql-5.1-rt50-merge


mysql-test/r/sp.result:
  failed auto merge
mysql-test/t/sp.test:
  failed auto merge

mysql-test/r/handler_innodb.result:
  Post-merge: add Bug#30632 test case result
mysql-test/r/handler_myisam.result:
  Post-merge fix of error number

into  moksha.local:/Users/davi/mysql/push/bugs/30632-5.1


sql/sql_handler.cc:
  Auto merged
mysql-test/include/handler.inc:
  Auto merged
mysql-test/r/handler_myisam.result:
  Auto merged

comments)

Before this fix, the server would accept queries that contained comments,
even when the comments were not properly closed with a '*' '/' marker.

For example,
  select 1 /* + 2 <EOF>
would be accepted as
  select 1 /* + 2 */ <EOF>
and executed as
  select 1

With this fix, the server now rejects queries with unclosed comments
as syntax errors.
Both regular comments ('/' '*') and special comments ('/' '*' '!') must be
closed with '*' '/' to be parsed correctly.


mysql-test/r/comments.result:
  Unbalanced comments are a syntax error.
mysql-test/t/comments.test:
  Unbalanced comments are a syntax error.
sql/sql_lex.cc:
  Unbalanced comments are a syntax error.

Bug#21422 GRANT/REVOKE possible inside stored function, probably in a trigger
Bug#17244 GRANT gives strange error message when used in a stored function

GRANT/REVOKE statements are non-transactional (no explicit transaction
boundaries) in nature and hence are forbidden inside stored functions and
triggers, but they weren't being effectively forbidden. Furthermore, the
absence of implict commits makes changes made by GRANT/REVOKE statements to
not be rolled back.

The implemented fix is to issue a implicit commit with every GRANT/REVOKE
statement, effectively prohibiting these statements in stored functions
and triggers. The implicit commit also fixes the replication bug, and looks
like being in concert with the behavior of DDL and administrative statements.

Since this is a incompatible change, the following sentence should be
added to the Manual in the very end of the 3rd paragraph, subclause
13.4.3 "Statements That Cause an Implicit Commit": "Beginning with
MySQL 5.0.??, the GRANT and REVOKE statements cause an implicit commit."

Patch contributed by Vladimir Shebordaev


mysql-test/r/sp-error.result:
  Test case result for Bug#17244
mysql-test/t/sp-error.test:
  Test case for Bug#17244
sql/sp_head.cc:
  Set that a procedure with GRANT/REVOKE command has a (implicit or explicit)
  commit.
sql/sql_parse.cc:
  End active transaction in SQLCOM_GRANT and SQLCOM_REVOKE, and thus effectively
  prohibit these statements in stored functions and triggers. An implicit commit
  also fixes a bug in replication, when GRANT or REVOKE would disappear from the
  binary log in case of a subsequent ROLLBACK, since they were considered
  transactional statements.
mysql-test/suite/rpl/r/rpl_binlog_grant.result:
  Add test case result for Bug#21975
mysql-test/suite/rpl/t/rpl_binlog_grant.test:
  Add test case for Bug#21975

seems to be converted as varbinary.

The bug has been already fixed. This CS just adds a test case for it.


mysql-test/r/sp.result:
  Update result file.
mysql-test/t/sp.test:
  Test case for BUG#13675.

into  weblab.(none):/home/marcsql/TREE/mysql-5.1-rt50-merge

into  moksha.local:/Users/davi/mysql/push/mysql-5.0-runtime

into  weblab.(none):/home/marcsql/TREE/mysql-5.1-rt50-merge


sql/sql_yacc.yy:
  automerge failed.

This is a performance bug, affecting in particular the bison generated code
for the parser.

Prior to this fix, the grammar used a long chain of reduces to parse an
expression, like:
  bit_expr -> bit_term
  bit_term -> bit_factor
  bit_factor -> value_expr
  value_expr -> term
  term -> factor
etc

This chain of reduces cause the internal state automaton in the generated
parser to execute more state transitions and more reduces, so that the
generated MySQLParse() function would spend a lot of time looping to execute
all the grammar reductions.

With this patch, the grammar has been reorganized so that rules are more
"flat", limiting the depth of reduces needed to parse <expr>.

Tests have been written to enforce that relative priorities and properties
of operators have not changed while changing the grammar.

See the bug report for performance data.


mysql-test/r/parser_precedence.result:
  Improved test coverage for operator precedence
mysql-test/t/parser_precedence.test:
  Improved test coverage for operator precedence
sql/sql_yacc.yy:
  Simplified the grammar to improve performances

If, after the tables are locked, one of the conditions to read from a
HANDLER table is not met, the handler code wrongly jumps to a error path
that won't unlock the tables.

The user-visible effect is that after a error in a handler read command,
all subsequent handler operations on the same table will hang.

The fix is simply to correct the code to jump to the (same) error path that
unlocks the tables.


mysql-test/r/handler.result:
  Bug#30632 test case result
mysql-test/t/handler.test:
  Bug#30632 test case
sql/sql_handler.cc:
  Always unlock the internal and external table level locks if any of the conditions
  (including errors) to read from a HANDLER table are not met.

into  moksha.local:/Users/davi/mysql/push/bugs/29936-5.1

into  moksha.local:/Users/davi/mysql/push/bugs/25164-5.1


sql/lock.cc:
  Auto merged
mysql-test/include/deadlock.inc:
  Auto merged
mysql-test/r/deadlock_innodb.result:
  Auto merged

The problem from a user's perspective: user creates table A, and then tries
to CREATE TABLE a SELECT from A - and this causes a deadlock error, a hang,
or fails with a debug assert, but only if the storage engine is InnoDB.

The origin of the problem: InnoDB uses case-insensitive collation
(system_charset_info) when looking up the internal table share, thus returning
the same share for 'a' and 'A'.

Cause of the user-visible behavior: since the same share is returned to SQL
locking subsystem, it assumes that the same table is first locked (within the
same session) for WRITE, and then for READ, and returns a deadlock error.
However, the code is wrong in not properly cleaning up upon an error, leaving
external locks in place, which leads to assertion failures and hangs.

Fix that has been implemented: the SQL layer should properly propagate the
deadlock error, cleaning up and freeing all resources.

Further work towards a more complete solution: InnoDB should not use case
insensitive collation for table share hash if table names on disk honor the case.


mysql-test/r/innodb-deadlock.result:
  Bug#25164 test case result
mysql-test/t/innodb-deadlock.test:
  Bug#25164 test case. The CREATE TABLE may fail depending on the character set
  of the system and filesystem, but it should never hang.
sql/lock.cc:
  Unlock the storage engine "external" table level locks, if the MySQL thr_lock
  locking subsystem detects a deadlock error.

This test case uses the wait_condition helper (only available in 5.1) in order to wait till the select/update opens and locks the table.


mysql-test/r/sp.result:
  Test case result for bug 29936
mysql-test/t/sp.test:
  Test case for bug 29936

into  weblab.(none):/home/marcsql/TREE/mysql-5.1-cleanup

sql/sql_yacc.yy:
  
  Whitespace cleaup

into  adventure.(none):/home/thek/Development/cpp/mysql-5.1-runtime

Test case contains possible race conditions. This patch fixes these race
conditions and also adjust the test to execute according to its documentation.


mysql-test/r/events.result:
  Modified test case to fit test documentation
mysql-test/t/events.test:
  Modified test case to fit test documentation

into  weblab.(none):/home/marcsql/TREE/mysql-5.1-cleanup


BUILD/SETUP.sh:
  Auto merged

since this flag was explicitly removed in pushbuild for GCOV builds.

 BUILD_CMD => ['sh', '-c', 'perl -i.bak -pe "s/ \\\\\$static_link//" ' .
              'BUILD/compile-pentium-gcov; BUILD/compile-pentium-gcov'],

Moving $static_link to SETUP.sh broke this, and is now fixed.

Should this flag be needed on some platforms,
the proper location is compile-<platform>-gcov

Tested the amd64 and pentium64 build fine without it, and can run NDB tests.


BUILD/SETUP.sh:
  Removed $static_link from GCOV builds.

Before this patch, the parser would execute:
- Select->expr_list.push_front()
- Select->expr_list.pop()
when parsing expressions lists, in the following rules:
- udf_expr_list
- expr_list
- ident_list

This is unnecessary, and introduces overhead due to the memory allocations
performed with Select->expr_list

With this patch, this code has been removed.
The list being parsed is maintained in the parser stack instead.

Also, 'udf_expr_list' has been renamed 'opt_udf_expr_list', since this
production can be empty.


sql/sql_lex.cc:
  Removed unused attribute expr_list
sql/sql_lex.h:
  Removed unused attribute expr_list
sql/sql_yacc.yy:
  Improved performances when parsing expression lists

into  weblab.(none):/home/marcsql/TREE/mysql-5.1-rt50-merge


BUILD/SETUP.sh:
  Auto merged
mysql-test/r/query_cache.result:
  Auto merged
mysql-test/t/query_cache.test:
  Auto merged
sql/item_cmpfunc.h:
  Auto merged

into  weblab.(none):/home/marcsql/TREE/mysql-5.0-30237

into  weblab.(none):/home/marcsql/TREE/mysql-5.0-23062

into  weblab.(none):/home/marcsql/TREE/mysql-5.0-30237


sql/sql_yacc.yy:
  Auto merged

This is a performance bug, related to the parsing or 'OR' and 'AND' boolean
expressions.

Let N be the number of expressions involved in a OR (respectively AND).

When N=1

For example, "select 1" involve only 1 term: there is no OR operator.

In 4.0 and 4.1, parsing expressions not involving OR had no overhead.
In 5.0, parsing adds some overhead, with Select->expr_list.

With this patch, the overhead introduced in 5.0 has been removed,
so that performances for N=1 should be identical to the 4.0 performances,
which are optimal (there is no code executed at all)

The overhead in 5.0 was in fact affecting significantly some operations.
For example, loading 1 Million rows into a table with INSERTs,
for a table that has 100 columns, leads to parsing 100 Millions of
expressions, which means that the overhead related to Select->expr_list
is executed 100 Million times ...

Considering that N=1 is by far the most probable expression,
this case should be optimal.

When N=2

For example, "select a OR b" involves 2 terms in the OR operator.

In 4.0 and 4.1, parsing expressions involving 2 terms created 1 Item_cond_or
node, which is the expected result.
In 5.0, parsing these expression also produced 1 node, but with some extra
overhead related to Select->expr_list : creating 1 list in Select->expr_list
and another in Item_cond::list is inefficient.

With this patch, the overhead introduced in 5.0 has been removed
so that performances for N=2 should be identical to the 4.0 performances.
Note that the memory allocation uses the new (thd->mem_root) syntax
directly.
The cost of "is_cond_or" is estimated to be neglectable: the real problem
of the performance degradation comes from unneeded memory allocations.

When N>=3

For example, "select a OR b OR c ...", which involves 3 or more terms.

In 4.0 and 4.1, the parser had no significant cost overhead, but produced
an Item tree which is difficult to evaluate / optimize during runtime.
In 5.0, the parser produces a better Item tree, using the Item_cond
constructor that accepts a list of children directly, but at an extra cost
related to Select->expr_list.

With this patch, the code is implemented to take the best of the two
implementations:
- there is no overhead with Select->expr_list
- the Item tree generated is optimized and flattened.

This is achieved by adding children nodes into the Item tree directly,
with Item_cond::add(), which avoids the need for temporary lists and memory
allocation

Note that this patch also provide an extra optimization, that the previous
code in 5.0 did not provide: expressions are flattened in the Item tree,
based on what the expression already parsed is, and not based on the order
in which rules are reduced.

For example : "(a OR b) OR c", "a OR (b OR c)" would both be represented
with 2 Item_cond_or nodes before this patch, and with 1 node only with this
patch. The logic used is based on the mathematical properties of the OR
operator (it's associative), and produces a simpler tree.


sql/item_cmpfunc.h:
  Improved performances for parsing boolean expressions
sql/sql_yacc.yy:
  Improved performances for parsing boolean expressions
mysql-test/r/parser_precedence.result:
  Added test cases to cover boolean operator precedence
mysql-test/t/parser_precedence.test:
  Added test cases to cover boolean operator precedence

into  adventure.(none):/home/thek/Development/cpp/mysql-5.0-runtime


mysql-test/r/query_cache.result:
  Auto merged
mysql-test/t/query_cache.test:
  Auto merged