large table gives server crash": make sure that when a MyISAM temporary
table is created for a cursor, it's created in its memory root,
not the memory root of the current query.
Procedure analyse() redefines select's fields_list. setup_copy_fields() assumes
that fields_list is a part of all_fields_list. Because select have only
3 columns and analyse() redefines it to have 10 columns, int overrun in
setup_copy_fields() occurs and server goes to almost infinite loop.
Because fields_list used not only to send data ad fields types, it's wrong
to allow procedure redefine it. This patch separates select's fileds_list
and procedure's one. Now if procedure is present, copy of fields_list is
created in procedure_fields_list and it is used for sending data and fields.
Date field was declared as not null, thus expression 'datefield is null'
was always false. For SELECT special handling of such cases is used.
There 'datefield is null' converted to 'datefield eq "0000-00-00"'.
In mysql_update() before creation of select added remove_eq_conds() call.
It makes some optimization of conds and in particular performs conversion
from 'is null' to 'eq'.
Also remove_eq_conds() makes some evaluation of conds and if it founds that
conds is always false then update statement is not processed further.
All this allows to perform some update statements process faster due to
optimized conds, and not wasting resources if conds known to be false.
DISTINCT wasn't optimized away and caused creation of tmp table in wrong
case. This result in integer overrun and running out of memory.
Fix backported from 4.1. Now if optimizer founds that in result be only 1
row it removes distinct.
field::sort_key() now adds length last for varbinary/blob
VARBINARY/BLOB is now sorted by filesort so that shorter strings comes before longer ones
Fixed issues in test cases from last merge
- CHAR() now returns binary string as default
- CHAR(X*65536+Y*256+Z) is now equal to CHAR(X,Y,Z) independent of the character set for CHAR()
- Test for both ETIMEDOUT and ETIME from pthread_cond_timedwait()
(Some old systems returns ETIME and it's safer to test for both values
than to try to write a wrapper for each old system)
- Fixed new introduced bug in NOT BETWEEN X and X
- Ensure we call commit_by_xid or rollback_by_xid for all engines, even if one engine has failed
- Use octet2hex() for all conversion of string to hex
- Simplify and optimize code
check_equality() finds equalities among field items. It checks input items
to be Item_fields thus skipping view's fields, which are represented by
Item_direct_view_ref. Because of this index wasn't applied in all cases
it can be.
To fix this problem check_equality() now takes real item of
Item_direct_view_ref, except outer view refs (with depended_from set).
When fixing Item_func_plus in ORDER BY clause field c is searched in all
opened tables, but because c is an alias it wasn't found there.
This patch adds a flag to select_lex which allows Item_field::fix_fields()
to look up in select's item_list to find aliased fields.
Fixed problems in test suite where some test failed
Fixed access to not initialized memory in federated
Fixed access to not initialized memory when using BIT fields in internal temporary tables
cursor is interpreted latin1 character and Bug#9819 "Cursors: Mysql Server
Crash while fetching from table with 5 million records."
A fix for a possible memory leak when fetching into an SP cursor
in a long loop.
The patch uses a common implementation of cursors in the binary protocol and
in stored procedures and implements materialized cursors.
For implementation details, see comments in sql_cursor.cc
For queries with GROUP BY and without hidden GROUP BY fields DISTINCT is
optimized away becuase such queries produce result set without duplicates.
But ROLLUP can add rows which may be same to some rows and this fact was
ignored.
Added check so if ROLLUP is present DISTINCT can't be optimized away.