a second time". The bug was caused by incompatibility of
negations elimination algorithm and PS: during first statement
execute a subtree with negation was replaced with equivalent
subtree without NOTs.
The problem was that although this transformation was permanent,
items of the new subtree were created in execute-local memory.
The patch adds means to check if it is the first execute of a
prepared statement, and if this is the case, to allocate items
in memory of the prepared statement.
The implementation:
- backports Item_arena from 5.0
- adds Item_arena::is_stmt_prepare(),
Item_arena::is_first_stmt_execute().
- deletes THD::allocate_temporary_pool_for_ps_preparing(),
THD::free_temporary_pool_for_ps_preparing(); they
were redundant.
and adds a few invariants:
- thd->free_list never contains junk (= freed items)
- thd->current_arena is never null. If there is no
prepared statement, it points at the thd.
The rest of the patch contains mainly mechanical changes and
cleanups.
more logical table/index_flags
return HA_ERR_WRONG_COMMAND instead of abstract methods where appropriate
max_keys and other limits renamed to max_supported_keys/etc
max_keys/etc are now wrappers to max_supported_keys/etc
ha_index_init/ha_rnd_init/ha_index_end/ha_rnd_end are now wrappers to real {index,rnd}_{init,end} to enforce strict pairing
Cleaned up embedded library access and query cache handling
Changed min stack size to 128K (to allow longer MyISAM keys)
Fixed wrong priority for XOR (should be less than NEG to get -1^1 to work)
This bug happens when a query, having subselects in the fields list,
needs temporary table.
Item_subselect::get_tmp_table_item isn't implemented and just returns
*this. So the tmp_table_item takes value not from temporary but
from original table.
Fixed compiler warnings (a lot of hidden variables detected by the Forte compiler)
Added a lot of 'version_xxx' strings to 'show variables'
Prevent copying of TMP_TABLE_PARAM (This caused core dump bug on Solaris)
Fixed problem with printing sub selects to debug log
