GitLab

sql/opt_range.cc:
  WL#3352 code review fixes
  
  Corrected indenting and added range_par parameter for easier reading/formatting.
sql/partition_element.h:
  WL#3352, changed formatting of copyright header
sql/sql_partition.cc:
  WL#3352, fixed indenting and changed MAX_VALUE to MAXVALUE
sql/sql_partition.h:
  WL#3352, fixed copyright header and indenting of
  function header

Changed all no_ to num_ to avoid strange names like no_list_values which is not expected to be number of list values, rather a boolea indicating no list values

WL#3352, Introducing Column list partitioning, makes it possible to partition on most data types, makes it possible to prune on multi-field partitioning

            results in server crash 
 
check_group_min_max_predicates() assumed the input condition 
item to be one of COND_ITEM, SUBSELECT_ITEM, or FUNC_ITEM. 
Since a condition of the form "field" is also a valid condition 
equivalent to "field <> 0", using such a condition in a query 
where the loose index scan was chosen resulted in a debug 
assertion failure. 
 
Fixed by handling conditions of the FIELD_ITEM type in 
check_group_min_max_predicates(). 

mysql-test/r/group_min_max.result:
  Added a test case for bug #46607.
mysql-test/t/group_min_max.test:
  Added a test case for bug #46607.
sql/opt_range.cc:
  Handle conditions of the FUNC_ITEM type in 
  check_group_mix_max_predicates().

with gcc 4.3.2
      
This patch fixes a number of GCC warnings about variables used
before initialized. A new macro UNINIT_VAR() is introduced for
use in the variable declaration, and LINT_INIT() usage will be
gradually deprecated. (A workaround is used for g++, pending a
patch for a g++ bug.)
      
GCC warnings for unused results (attribute warn_unused_result)
for a number of system calls (present at least in later
Ubuntus, where the usual void cast trick doesn't work) are
also fixed.


client/mysqlmanager-pwgen.c:
  A fix for warn_unused_result, adding fallback to use of
  srand()/rand() if /dev/random cannot be used. Also actually
  adds calls to rand() in the second branch so that it actually
  creates a random password.

Problem was that the partition containing NULL values
was pruned away, since '2001-01-01' < '2001-02-00' but
TO_DAYS('2001-02-00') is NULL.

Added the NULL partition for RANGE/LIST partitioning on TO_DAYS()
function to be scanned too.

Also fixed a bug that added ALLOW_INVALID_DATES to sql_mode
(SELECT * FROM t WHERE date_col < '1999-99-99' on a RANGE/LIST
partitioned table would add it).

mysql-test/include/partition_date_range.inc:
  Bug#20577: Partitions: use of to_days() function leads to selection failures
  
  Added include file to decrease test code duplication
mysql-test/r/partition_pruning.result:
  Bug#20577: Partitions: use of to_days() function leads to selection failures
  
  Added test results
mysql-test/r/partition_range.result:
  Bug#20577: Partitions: use of to_days() function leads to selection failures
  
  Updated test result.
  This fix adds the partition containing NULL values to
  the list of partitions to be scanned.
mysql-test/t/partition_pruning.test:
  Bug#20577: Partitions: use of to_days() function leads to selection failures
  
  Added test case
sql/item.h:
  Bug#20577: Partitions: use of to_days() function leads to selection failures
  
  Added MONOTONIC_*INCREASE_NOT_NULL values to be used by TO_DAYS.
sql/item_timefunc.cc:
  Bug#20577: Partitions: use of to_days() function leads to selection failures
  
  Calculate the number of days as return value even for invalid dates.
  This is so that pruning can be used even for invalid dates.
sql/opt_range.cc:
  Bug#20577: Partitions: use of to_days() function leads to selection failures
  
  Fixed a bug that added ALLOW_INVALID_DATES to sql_mode
  (SELECT * FROM t WHERE date_col < '1999-99-99' on a RANGE/LIST
  partitioned table would add it).
sql/partition_info.h:
  Bug#20577: Partitions: use of to_days() function leads to selection failures
  
  Resetting ret_null_part when a single partition is to be used, this
  to avoid adding the NULL partition.
sql/sql_partition.cc:
  Bug#20577: Partitions: use of to_days() function leads to selection failures
  
  Always include the NULL partition if RANGE or LIST.
  Use the returned value for the function for pruning, even if
  it is marked as NULL, so that even '2000-00-00' can be
  used for pruning, even if TO_DAYS('2000-00-00') is NULL.
  
  Changed == to >= in get_next_partition_id_list to avoid
  crash if part_iter->part_nums is not correctly setup.

There were a problem since pruning uses the field
for comparison (while evaluate_join_record uses longlong),
resulting in pruning failures when comparing DATE to DATETIME.

Fix was to always comparing DATE vs DATETIME as DATETIME,
by adding ' 00:00:00' to the DATE string.

And adding optimization for comparing with 23:59:59, so that
DATETIME_col > '2001-02-03 23:59:59' ->
TO_DAYS(DATETIME_col) > TO_DAYS('2001-02-03 23:59:59') instead
of '>='.

mysql-test/r/partition_pruning.result:
  Bug#46362: Endpoint should be set to false for TO_DAYS(DATE)
  
  Updated result-file
mysql-test/t/partition_pruning.test:
  Bug#46362: Endpoint should be set to false for TO_DAYS(DATE)
  
  Added testcases.
sql-common/my_time.c:
  Bug#46362: Endpoint should be set to false for TO_DAYS(DATE)
  
  removed duplicate assignment.
sql/item.cc:
  Bug#46362: Endpoint should be set to false for TO_DAYS(DATE)
  
  Changed field_is_equal_to_item into field_cmp_to_item, to
  better handling DATE vs DATETIME comparision.
sql/item.h:
  Bug#46362: Endpoint should be set to false for TO_DAYS(DATE)
  
  Updated comment
sql/item_timefunc.cc:
  Bug#46362: Endpoint should be set to false for TO_DAYS(DATE)
  
  Added optimization (pruning) of DATETIME where time-part is
  23:59:59
sql/opt_range.cc:
  Bug#46362: Endpoint should be set to false for TO_DAYS(DATE)
  
  Using the new stored_field_cmp_to_item for better pruning.

The code was using a special global buffer for the value of IS NULL ranges.
This was not always long enough to be copied by a regular memcpy. As a 
result read buffer overflows may occur.
Fixed by setting the null byte to 1 and setting the rest of the field disk image
to NULL with a bzero (instead of relying on the buffer and memcpy()).

The check for stack overflow was independent of the size of the 
structure stored in the heap. 
Fixed by adding sizeof(PARAM) to the requested free heap size.

       
Fixed various compilation warnings when compiling on a 
 64 bit windows.

When the function exits with an error it was not
freeing the local Unique class instance.
Fixed my making sure all the places where the function
returns from are freeing the Unique instance 

WHERE and GROUP BY clause

Loose index scan may use range conditions on the argument of 
the MIN/MAX aggregate functions to find the beginning/end of 
the interval that satisfies the range conditions in a single go.
These range conditions may have open or closed minimum/maximum 
values. When the comparison returns 0 (equal) the code should 
check the type of the min/max values of the current interval 
and accept or reject the row based on whether the limit is 
open or not.
There was a wrong composite condition on checking this and it was
not working in all cases.
Fixed by simplifying the conditions and reversing the logic.

mysql-test/r/group_min_max.result:
  Bug #45386: test case
mysql-test/t/group_min_max.test:
  Bug #45386: test case
sql/opt_range.cc:
  Bug #45386: fix the check whether to use the value if on the
  interval boundry

Range analysis did not request sorted output from the storage engine,
which cause partitioned handlers to process one partition at a time
while reading key prefixes in ascending order, causing values to be 
missed. Fixed by always requesting sorted order during range analysis.
This fix is introduced in 6.0 by the fix for bug no 41136.

mysql-test/r/group_min_max.result:
  Bug#44821: Test result.
mysql-test/t/group_min_max.test:
  Bug#44821: Test case
sql/opt_range.cc:
  Bug#44821: Fix.

with gcc 4.3.2
      
Compiling MySQL with gcc 4.3.2 and later produces a number of 
warnings, many of which are new with the recent compiler
versions.
      
This bug will be resolved in more than one patch to limit the
size of changesets. This is the first patch, fixing a number 
of the warnings, predominantly "suggest using parentheses 
around && in ||", and empty for and while bodies.

with gcc 4.3.2

Compiling MySQL with gcc 4.3.2 and later produces a number of 
warnings, many of which are new with the recent compiler
versions.

This bug will be resolved in more than one patch to limit the
size of changesets. This is the first patch, fixing a number 
of the warnings, predominantly "suggest using parentheses 
around && in ||", and empty for and while bodies.

mysql-test/r/index_merge_myisam.result:
  Testcases
mysql-test/t/index_merge_myisam.test:
  Testcases
sql/strfunc.cc:
  Change optimizer_switch from no_xxx to xxx=on/xx=off.
  - Add functions to parse the new syntax

return no rows

The algorithm of determining the best key for loose index scan is doing a loop
over the available indexes and selects the one that has the best cost.
It retrieves the parameters of the current index into a set of variables.
If the cost of using the current index is lower than the best cost so far it 
copies these variables into another set of variables that contain the 
information for the best index so far.
After having checked all the indexes it uses these variables (outside of the 
index loop) to create the table read plan object instance.
The was a single omission : the key_infix/key_infix_len variables were used 
outside of the loop without being preserved in the loop for the best index 
so far.
This causes these variables to get overwritten by the next index(es) checked.
Fixed by adding variables to hold the data for the current index, passing 
the new variables to the function that assigns values to them and copying 
the new variables into the existing ones when selecting a new current best 
index.
To avoid further such problems moved the declarations of the variables used 
to keep information about the current index inside the loop's compound 
statement.

mysql-test/r/group_min_max.result:
  Bug #41610: test case
mysql-test/t/group_min_max.test:
  Bug #41610: test case
sql/opt_range.cc:
  Bug #41610: copy the infix data for the current best index

- Add support for setting it as a server commandline argument
- Add support for those switches:
  = no_index_merge
  = no_index_merge_union
  = no_index_merge_sort_union
  = no_index_merge_intersection

mysql-test/r/index_merge_myisam.result:
  Testcases for index_merge related @@optimizer_switch flags.
mysql-test/t/index_merge_myisam.test:
  Testcases for index_merge related @@optimizer_switch flags.
sql/set_var.cc:
  - Backport @@optimizer_switch support from 6.0
  - Add support for setting it as a server commandline argument
sql/sql_class.h:
  - Backport @@optimizer_switch support from 6.0
sql/sql_select.h:
  - Backport @@optimizer_switch support from 6.0

- Remove bothersome warning messages.  This change focuses on the warnings 
that are covered by the ignore file: support-files/compiler_warnings.supp.
- Strings are guaranteed to be max uint in length

- QUICK_INDEX_MERGE_SELECT deinitializes its rnd_pos() scan when it reaches EOF, but we 
  need to make the deinitialization in QUICK_INDEX_MERGE_SELECT destructor also. This is because
  certain execution strategies can stop scanning without reaching EOF, then then try to do a full
  table scan on this table. Failure to deinitialize caused the full scan to use (already empty) 
  table->sort and produce zero records.

mysql-test/r/index_merge.result:
  BUG#40974: Incorrect query results when using clause evaluated using range check
  - Testcase
mysql-test/t/index_merge.test:
  BUG#40974: Incorrect query results when using clause evaluated using range check
  - Testcase

Field_varstring::store
      
The code that temporary saved the bitmaps of the read set and the write set so that
it can set it to all columns for debug purposes was not expecting that the
table->read_set and table->write_set can be the same. And was always saving both in 
sequence.
As a result the original value was never restored.
Fixed by saving & restoring the original value only once if the two sets are the
same (in a special set of functions).

mysql-test/r/select.result:
  Bug #37936: test case
mysql-test/t/select.test:
  Bug #37936: test case
sql/item_cmpfunc.cc:
  Bug #37936: don't save/restore twice if the read and write sets are the same
sql/opt_range.cc:
  Bug #37936: don't save/restore twice if the read and write sets are the same
sql/table.h:
  Bug #37936: Make a designated set of functions that save/restore
  both the read and the write sets in a single call.

since Oct 1st

Select with a "NULL NOT IN" condition containing complex
subselect from the same table as in the outer select failed
with an assertion.


The failure was caused by a concatenation of circumstances:
1) an inner select was optimized by make_join_statistics to use
   the QUICK_RANGE_SELECT access method (that implies an index
   scan of the table);
2) a subselect was independent (constant) from the outer select;
3) a condition was pushed down into inner select.

During the evaluation of a constant IN expression an optimizer
temporary changed the access method from index scan to table
scan, but an engine handler was already initialized for index
access by make_join_statistics. That caused an assertion.


Unnecessary index initialization has been removed from
the QUICK_RANGE_SELECT::init method (QUICK_RANGE_SELECT::reset
reinvokes this initialization).


mysql-test/r/subselect3.result:
  Added test case for bug #37894.
mysql-test/t/subselect3.test:
  Added test case for bug #37894.
sql/opt_range.cc:
  Bug #37894: Assertion in init_read_record_seq in handler.h line 1444
  
  Unnecessary index initialization has been removed from
  the QUICK_RANGE_SELECT::init method (QUICK_RANGE_SELECT::reset
  reinvokes this initialization).

crashes server

When creating temporary table that contains aggregate functions a 
non-reversible source transformation was performed to redirect aggregate
function arguments towards temporary table columns.
This caused EXPLAIN EXTENDED to fail because it was trying to resolve
references to the (freed) temporary table.
Fixed by preserving the original aggregate function arguments and
using them (instead of the transformed ones) for EXPLAIN EXTENDED.

mysql-test/r/explain.result:
  Bug#34773: test case
mysql-test/t/explain.test:
  Bug#34773: test case
sql/item.cc:
  Bug#34773: use accessor functions instead of public members
sql/item_sum.cc:
  Bug#34773: 
   - Encapsulate the arguments into Item_sum and
     provide accessor and mutator methods 
   - print the orginal arguments (if present)
     in EXPLAIN EXTENDED
   - preserve the original arguments list.
sql/item_sum.h:
  Bug#34773: 
   - Encapsulate the arguments into Item_sum and
     provide accessor and mutator methods 
   - print the orginal arguments (if present)
     in EXPLAIN EXTENDED
   - preserve the original arguments list.
sql/opt_range.cc:
  Bug#34773: use accessor functions instead of public members
sql/opt_sum.cc:
  Bug#34773: use accessor functions instead of public members
sql/sql_select.cc:
  Bug#34773: use accessor functions instead of public members

      
    problems are located in the sql_partition.cc where functions calculation
    partition_id don't expect error returned from item->val_int().
    Fixed by adding checks to these functions.
    Note  - it tries to fix more problems than just the reported bug.
      
per-file comments:
modified:
  mysql-test/r/partition.result
    Bug#38083 Error-causing row inserted into partitioned table despite error
        test result
  mysql-test/t/partition.test
    Bug#38083 Error-causing row inserted into partitioned table despite error
        test case
  sql/opt_range.cc
    Bug#38083 Error-causing row inserted into partitioned table despite error
        get_part_id() call fixed
  sql/partition_info.h
    Bug#38083 Error-causing row inserted into partitioned table despite error
        get_subpart_id_func interface changed. 
  sql/sql_partition.cc
    Bug#38083 Error-causing row inserted into partitioned table despite error
        various functions calculationg partition_id and subpart_id didn't expect
            an error returned from item->val_int().  Error checks added.

            
When analyzing the possible index use cases the server was re-using an internal structure.
This is wrong, as this internal structure gets updated during the analysis.
Fixed by making a copy of the internal structure for every place it needs to be used.
Also stopped the generation of empty SEL_TREE structures that unnecessary 
complicate the analysis.

mysql-test/r/index_merge.result:
  Bug#37943: test case
mysql-test/t/index_merge.test:
  Bug#37943: test case
sql/opt_range.cc:
  Bug#37943: 
   - Make copy constructors for SEL_TREE and sub-structures and use them when OR-ing trees.
   - don't generate empty SEL_TREEs. Return NULL instead.

- Use the compiler's default copy constructor for QUICK_RANGE_SELECT. 
  bcopy(this, copy, ...) call caused some odd action on gcc-4.1.2 on x86_64

sql/opt_range.cc:
  BUG#36639: subselect.test crashes on 64 bit pentium4 when compiled for valgrind
  - Set QUICK_SELECT_DESC not to use MRR implementation (code moved to here
    from opt_range.h)
sql/opt_range.h:
  BUG#36639: subselect.test crashes on 64 bit pentium4 when compiled for valgrind
  - Use the compiler's default copy constructor for QUICK_RANGE_SELECT. 
    bcopy(this, copy, ...) call caused some odd action on gcc-4.1.2 on x86_64

                  
Range scan in descending order for c <= <col> <= c type of
ranges was ignoring the DESC flag.
However some engines like InnoDB have the primary key parts 
as a suffix for every secondary key.
When such primary key suffix is used for ordering ignoring 
the DESC is not valid.
But we generally would like to do this because it's faster.
            
Fixed by performing only reverse scan if the primary key is used.
Removed some dead code in the process.

mysql-test/r/innodb_mysql.result:
  Bug#37830 : test case
mysql-test/t/innodb_mysql.test:
  Bug#37830 : test case
sql/opt_range.cc:
  Bug#37830 : 
  - preserve and use used_key_parts to
    distinguish when a primary key suffix is used
  - removed some dead code
sql/opt_range.h:
  Bug#37830 : 
  - preserve used_key_parts
  - dead code removed
sql/sql_select.cc:
  Bug#37830 : Do only reverse order traversal
  if the primary key suffix is used.

            
Range scan in descending order for c <= <col> <= c type of
ranges was ignoring the DESC flag.
However some engines like InnoDB have the primary key parts 
as a suffix for every secondary key.
When such primary key suffix is used for ordering ignoring 
the DESC is not valid.
But we generally would like to do this because it's faster.
      
Fixed by performing only reverse scan if the primary key is used.
Removed some dead code in the process.

mysql-test/r/innodb_mysql.result:
  Bug#37830 : test case
mysql-test/t/innodb_mysql.test:
  Bug#37830 : test case
sql/opt_range.cc:
  Bug#37830 : 
   - preserve and use used_key_parts to
     distinguish when a primary key suffix is used
   - removed some dead code
sql/opt_range.h:
  Bug#37830 : 
    - preserve used_key_parts
    - dead code removed
sql/sql_select.cc:
  Bug#37830 : Do only reverse order traversal
      if the primary key suffix is used.

- In QUICK_INDEX_MERGE_SELECT::read_keys_and_merge: when we got table->sort from Unique,
  tell init_read_record() not to use rr_from_cache() because a) rowids are already sorted
  and b) it might be that the the data is used by filesort(), which will need record rowids
  (which rr_from_cache() cannot provide).
- Fully de-initialize the table->sort read in QUICK_INDEX_MERGE_SELECT::get_next(). This fixes BUG#35477.
(bk trigger: file as fix for BUG#35478).

sql/filesort.cc:
  BUG#35478: sort_union() returns bad data when sort_buffer_size is hit
  - make find_all_keys() use quick->get_next() instead of init_read_record(r)/r.read_record() calls
  - added dbug printout
sql/mysql_priv.h:
  BUG#35478: sort_union() returns bad data when sort_buffer_size is hit
  - Added parameter to init_read_record
sql/opt_range.cc:
  BUG#35478: sort_union() returns bad data when sort_buffer_size is hit
  - In QUICK_INDEX_MERGE_SELECT::read_keys_and_merge: when we got table->sort from Unique,
    tell init_read_record() not to use rr_from_cache() because a) rowids are already sorted
    and b) it might be that the the data is used by filesort(), which will need record rowids
    (which rr_from_cache() cannot provide).
  - Fully de-initialize the table->sort read in QUICK_INDEX_MERGE_SELECT::get_next().
sql/records.cc:
  BUG#35478: sort_union() returns bad data when sort_buffer_size is hit
  - Added disable_rr_cache parameter to init_read_record
  - Added comment
sql/sql_acl.cc:
  BUG#35478: sort_union() returns bad data when sort_buffer_size is hit
  - Added parameter to init_read_record
sql/sql_delete.cc:
  BUG#35478: sort_union() returns bad data when sort_buffer_size is hit
  - Added parameter to init_read_record
sql/sql_help.cc:
  BUG#35478: sort_union() returns bad data when sort_buffer_size is hit
  - Added parameter to init_read_record
sql/sql_select.cc:
  BUG#35478: sort_union() returns bad data when sort_buffer_size is hit
  - Added parameter to init_read_record
sql/sql_table.cc:
  BUG#35478: sort_union() returns bad data when sort_buffer_size is hit
  - Added parameter to init_read_record
sql/sql_udf.cc:
  BUG#35478: sort_union() returns bad data when sort_buffer_size is hit
  - Added parameter to init_read_record
sql/sql_update.cc:
  BUG#35478: sort_union() returns bad data when sort_buffer_size is hit
  - Added parameter to init_read_record

sql/sp.h:
  Remove unused code.

- Backported the 5.1 DBUG to 5.0.
- Avoid memory cleanup race on Windows client for CTRL-C


client/mysql.cc:
  Bug#26243 mysql command line crash after control-c
  - On Windows, the sigint handler shouldn't call mysql_end
  because the main thread will do so automatically.
  - Remove unnecessary signal call from the sigint handler.
  - Call my_end with proper value.
dbug/dbug.c:
  Bug#26243 mysql command line crash after control-c
  - Backported the 5.1 DBUG library. The old version uses a non-thread 
  safe global variable 'static struct state *stack'.
dbug/factorial.c:
  Bug#26243 mysql command line crash after control-c
  - Backported the 5.1 DBUG library. The old version uses a non-thread 
  safe global variable 'static struct state *stack'.
dbug/user.r:
  Bug#26243 mysql command line crash after control-c
  - Backported the 5.1 DBUG library. The old version uses a non-thread 
  safe global variable 'static struct state *stack'.
include/my_dbug.h:
  B...

WHERE f1 < n ignored row if f1 was indexed integer column and
f1 = TYPE_MAX ^ n = TYPE_MAX+1. The latter value when treated
as TYPE overflowed (obviously). This was not handled, it is now.


mysql-test/r/range.result:
  show that on an index int column, we no longer disregard
  a field val of TYPE_MAX in SELECT ... WHERE ... < TYPE_MAX+1
mysql-test/t/range.test:
  show that on an index int column, we no longer disregard
  a field val of TYPE_MAX in SELECT ... WHERE ... < TYPE_MAX+1
sql/opt_range.cc:
  Handle overflowing of int-types in range-optimizer.
  Unfortunately requires re-indentation of entire block.
  Overflow (err == 1) was handled, but only if
  field->cmp_type() != value->result_type(), which it
  just wasn't in our case.

- Make conditions like "date_col $CMP$ 'datetime-const'" range-sargable


mysql-test/r/range.result:
  BUG#32198: Comparison of DATE with DATETIME still not using indexes correctly
  - Testcase
mysql-test/t/range.test:
  BUG#32198: Comparison of DATE with DATETIME still not using indexes correctly
  - Testcase
sql/field.cc:
  BUG#32198: Comparison of DATE with DATETIME still not using indexes correctly
  - Added comments

cause ROLLBACK of statement", part 1. Review fixes.

Do not send OK/EOF packets to the client until we reached the end of 
the current statement.
This is a consolidation, to keep the functionality that is shared by all 
SQL statements in one place in the server.
Currently this functionality includes:
- close_thread_tables()
- log_slow_statement().

After this patch and the subsequent patch for Bug#12713, it shall also include:
- ha_autocommit_or_rollback()
- net_end_statement()
- query_cache_end_of_result().

In future it may also include:
- mysql_reset_thd_for_next_command().


include/mysql_com.h:
  Rename now unused members of NET: no_send_ok, no_send_error, report_error.
  These were server-specific variables related to the client/server
  protocol. They have been made obsolete by this patch.
  
  Previously the same members of NET were used to store the error message
  both on the client and on the server. 
  The error message was stored in net.last_error (client: mysql->net.last_error,
  server: thd->net.last_error).
  The error code was stored in net.last_errno (client: mysql->net.last_errno,
  server: thd->net.last_errno).
  The server error code and message are now stored elsewhere 
  (in the Diagnostics_area), thus NET members are no longer used by the
  server.
  Rename last_error to client_last_error, last_errno to client_last_errno
  to avoid potential bugs introduced by merges.
include/mysql_h.ic:
  Update the ABI file to reflect a rename. 
  Renames do not break the binary compatibility.
libmysql/libmysql.c:
  Rename last_error to client_last_error, last_errno to client_last_errno.
  This is necessary to ensure no unnoticed bugs introduced by merged
  changesets.
  
  Remove net.report_error, net.no_send_ok, net.no_send_error.
libmysql/manager.c:
  Rename net.last_errno to net.client_last_errno.
libmysqld/lib_sql.cc:
  Rename net.last_errno to net.client_last_errno.
  
  Update the embedded implementation of the client-server protocol to
  reflect the refactoring of protocol.cc.
libmysqld/libmysqld.c:
  Rename net.last_errno to net.client_last_errno.
mysql-test/r/events.result:
  Update to reflect the change in mysql_rm_db(). Now we drop stored
  routines and events for a given database name only if there
  is a directory for this database name. ha_drop_database() and
  query_cache_invalidate() are called likewise. 
  Previously we would attempt to drop routines/events even if database
  directory was not found (it worked, since routines and events are stored
  in tables). This fixes Bug 29958 "Weird message on DROP DATABASE if mysql.proc
  does not exist".
  The change was done because the previous code used to call send_ok()
  twice, which led to an assertion failure when asserts against it were
  added by this patch.
mysql-test/r/grant.result:
  Fix the patch for Bug 16470, now FLUSH PRIVILEGES produces an error 
  if mysql.procs_priv is missing.
  This fixes the assert that send_ok() must not called after send_error()
  (the original patch for Bug 16470 was prone to this).
mysql-test/suite/rpl/r/rpl_row_tabledefs_2myisam.result:
  Produce a more detailed error message.
mysql-test/suite/rpl/r/rpl_row_tabledefs_3innodb.result:
  Produce a more detailed error message.
mysql-test/t/grant.test:
  Update the test, now FLUSH PRIVILEGES returns an error if mysql.procs_priv
  is missing.
server-tools/instance-manager/mysql_connection.cc:
  Rename net.last_errno to net.client_last_errno.
sql/ha_ndbcluster_binlog.cc:
  Add asserts. 
  
  Use getters to access statement status information.
  
  Add a comment why run_query() is broken. Reset the diagnostics area
  in the end of run_query() to fulfill the invariant that the diagnostics_area
  is never assigned twice per statement (see the comment in the code
  when this can happen). We still do not clear thd->is_fatal_error and
  thd->is_slave_error, which may lead to bugs, I consider the whole affair
  as something to be dealt with separately.
sql/ha_partition.cc:
  fatal_error() doesn't set an error by itself. Perhaps we should
  remove this method altogether and instead add a flag to my_error 
  to set thd->is_fatal_error property.
  
  Meanwhile, this change is a part of inspection made to the entire source
  code with the goal to ensure that fatal_error()
  is always accompanied by my_error().
sql/item_func.cc:
  There is no net.last_error anymore. Remove the obsolete assignment.
sql/log_event.cc:
  Use getters to access statement error status information.
sql/log_event_old.cc:
  Use getters to access statement error status information.
sql/mysqld.cc:
  Previously, if a continue handler for an error was found, my_message_sql() 
  would not set an error in THD. Since the current statement
  must be aborted in any case, find_handler() had a hack to assign 
  thd->net.report_error to 1.
  
  Remove this hack. Set an error in my_message_sql() even if the continue
  handler is found. The error will be cleared anyway when the handler
  is executed. This is one action among many in this patch to ensure the 
  invariant that whenever thd->is_error() is TRUE, we have a message in 
  thd->main_da.message().
sql/net_serv.cc:
  Use a full-blown my_error() in net_serv.cc to report an error,
  instead of just setting net->last_errno. This ensures the invariant that
  whenever thd->is_error() returns TRUE, we have a message in 
  thd->main_da.message().
  
  Remove initialization of removed NET members.
sql/opt_range.cc:
  Use my_error() instead of just raising thd->net.report_error. 
  This ensures the invariant that whenever thd->is_error() returns TRUE, 
  there is a message in thd->main_da.message().
sql/opt_sum.cc:
  Move invocation of fatal_error() right next to the place where
  we set the error message. That makes it easier to track that whenever
  fatal_error() is called, there is a message in THD.
sql/protocol.cc:
  Rename send_ok() and send_eof() to net_send_ok() and net_send_eof() 
  respectively. These functions write directly to the network and are not 
  for use anywhere outside the client/server protocol code. 
  
  Remove the code that was responsible for cases when either there is 
  no error code, or no error message, or both.
  Instead the calling code ensures that they are always present. Asserts
  are added to enforce the invariant.
  
  Instead of a direct access to thd->server_status and thd->total_warn_count
  use function parameters, since these from now on don't always come directly
  from THD.
  
  Introduce net_end_statement(), the single-entry-point replacement API for 
  send_ok(), send_eof() and net_send_error().
  
  Implement Protocol::end_partial_result_set to use in select_send::abort()
  when there is a continue handler.
sql/protocol.h:
  Update declarations.
sql/repl_failsafe.cc:
  Use getters to access statement status information in THD.
  Rename net.last_error to net.client_last_error.
sql/rpl_record.cc:
  Set an error message in prepare_record() if there is no default
  value for the field -- later we do print this message to the client.
sql/rpl_rli.cc:
  Use getters to access statement status information in THD.
sql/slave.cc:
  In create_table_from_dump() (a common function that is used in 
  LOAD MASTER TABLE SQL statement and COM_LOAD_MASTER_DATA), instead of hacks
  with no_send_ok, clear the diagnostics area when mysql_rm_table() succeeded.
  
  Update has_temporary_error() to work correctly when no error is set.
  This is the case when Incident_log_event is executed: it always returns
  an error but does not set an error message.
  
  Use getters to access error status information.
sql/sp_head.cc:
  Instead of hacks with no_send_error, work through the diagnostics area 
  interface to suppress sending of OK/ERROR packets to the client.
  
  Move query_cache_end_of_result before log_slow_statement(), similarly
  to how it's done in dispatch_command().
sql/sp_rcontext.cc:
  Remove hacks with assignment of thd->net.report_error, they are not
  necessary any more (see the changes in mysqld.cc).
sql/sql_acl.cc:
  Use getters to access error status information in THD.
sql/sql_base.cc:
  Access thd->main_da.sql_errno() only if there is an error. This fixes
  a bug when auto-discovery, that was effectively disabled under pre-locking.
sql/sql_binlog.cc:
  Remove hacks with no_send_ok/no_send_error, they are not necessary 
  anymore: the caller is responsible for network communication.
sql/sql_cache.cc:
  Disable sending of OK/ERROR/EOF packet in the end of dispatch_command
  if the response has been served from the query cache. This raises the 
  question whether we should store EOF packet in the query cache at all,
  or generate it anew for each statement (we should generate it anew), but
  this is to be addressed separately.
sql/sql_class.cc:
  Implement class Diagnostics_area. Please see comments in sql_class.h
  for details.
  
  Fix a subtle coding mistake in select_send::send_data: when on slave, 
  an error in Item::send() was ignored.
  The problem became visible due to asserts that the diagnostics area is
  never double assigned.
  
  Remove initialization of removed NET members.
  
  In select_send::abort() do not call select_send::send_eof(). This is
  not inheritance-safe. Even if a stored procedure continue handler is
  found, the current statement is aborted, not succeeded.
  Instead introduce a Protocol API to send the required response, 
  Protocol::end_partial_result_set().
  
  This simplifies implementation of select_send::send_eof(). No need
  to add more asserts that there is no error, there is an assert inside
  Diagnostics_area::set_ok_status() already.
  
  Leave no trace of no_send_* in the code.
sql/sql_class.h:
  Declare class Diagnostics_area. 
  
  Remove the hack with no_send_ok from
  Substatement_state.
  
  Provide inline implementations of send_ok/send_eof.
  
  Add commetns.
sql/sql_connect.cc:
  Remove hacks with no_send_error. 
  
  Since now an error in THD is always set if net->error, it's not necessary
  to check both net->error and thd->is_error() in the do_command loop.
  
  Use thd->main_da.message() instead of net->last_errno.
  
  Remove the hack with is_slave_error in sys_init_connect. Since now we do not
  reset the diagnostics area in net_send_error (it's reset at the beginning
  of the next statement), we can access it safely even after 
  execute_init_command.
sql/sql_db.cc:
  Update the code to satisfy the invariant that the diagnostics area is never
  assigned twice.
  Incidentally, this fixes Bug 29958 "Weird message on DROP DATABASE if 
  mysql.proc does not exist".
sql/sql_delete.cc:
  Change multi-delete to abort in abort(), as per select_send protocol.
  Fixes the merge error with the test for Bug 29136
sql/sql_derived.cc:
  Use getters to access error information.
sql/sql_insert.cc:
  Use getters to access error information.
sql-common/client.c:
  Rename last_error to client_last_error, last_errno to client_last_errno.
sql/sql_parse.cc:
  Remove hacks with no_send_error. Deploy net_end_statement().
  
  The story of COM_SHUTDOWN is interesting. Long story short, the server 
  would become on its death's door, and only no_send_ok/no_send_error assigned
  by send_ok()/net_send_error() would hide its babbling from the client.
  
  First of all, COM_QUIT does not require a response. So, the comment saying
  "Let's send a response to possible COM_QUIT" is not only groundless 
  (even mysqladmin shutdown/mysql_shutdown() doesn't send COM_QUIT after 
  COM_SHUTDOWN), it's plainly incorrect.
  
  Secondly, besides this additional 'OK' packet to respond to a hypothetical
  COM_QUIT, there was the following code in dispatch_command():
  
  if (thd->killed)
    thd->send_kill_message();
  if (thd->is_error()
    net_send_error(thd);
  
  This worked out really funny for the thread through which COM_SHUTDOWN
  was delivered: we would get COM_SHUTDOWN, say okay, say okay again, 
  kill everybody, get the kill signal ourselves, and then attempt to say 
  "Server shutdown in progress" to the client that is very likely long gone.
  
  This all became visible when asserts were added that the Diagnostics_area
  is not assigned twice.
  
  Move query_cache_end_of_result() to the end of dispatch_command(), since
  net_send_eof() has been moved there. This is safe, query_cache_end_of_result()
  is a no-op if there is no started query in the cache.
  
  Consistently use select_send interface to call abort() or send_eof()
  depending on the operation result.
  
  Remove thd->fatal_error() from reset_master(), it was a no-op. 
  in hacks with no_send_error woudl save us
  from complete breakage of the client/server protocol.
  
  Consistently use select_send::abort() whenever there is an error, 
  and select_send::send_eof() in case of success.
  The issue became visible due to added asserts.
sql/sql_partition.cc:
  Always set an error in THD whenever there is a call to fatal_error().
sql/sql_prepare.cc:
  Deploy class Diagnostics_area.
  Remove the unnecessary juggling with the protocol in 
  Select_fetch_protocol_binary::send_eof(). EOF packet format is 
  protocol-independent.
sql/sql_select.cc:
  Call fatal_error() directly in opt_sum_query.
  Call my_error() whenever we call thd->fatal_error().
sql/sql_servers.cc:
  Use getters to access error information in THD.
sql/sql_show.cc:
  Use getters to access error information in THD.
  
  Add comments.
  
  Call my_error() whenever we call fatal_error().
sql/sql_table.cc:
  Replace hacks with no_send_ok with the interface of the diagnostics area.
  
  Clear the error if ENOENT error in ha_delete_table().
sql/sql_update.cc:
  Introduce multi_update::abort(), which is the proper way to abort a
  multi-update. This fixes the merge conflict between this patch and
  the patch for Bug 29136.
sql/table.cc:
  Use a getter to access error information in THD.
sql/tztime.cc:
  Use a getter to access error information in THD.

                  memory corruptions.

The right pointer field of the SEL_ARG structure was not
initialized in the constructor and sometimes that led to
server crashes.

There is no testcase because the bug occurs only when
uninitialized memory has particular values, which can't be
re-created in the test suite.


sql/opt_range.cc:
  Fixed bug #32403.
  
  The eq_tree function requires that SEL_ARG::left and
  SEL_ARG::right are equal to null pointer if SEL_ARG
  type is MAYBE_KEY, but SEL_ARG::right was not initialized
  and contained garbage.