mirror/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-01-16 12:02:42 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions

Bug#15843818 PARTITIONING BY RANGE WITH TO_DAYS ALWAYS

Browse source 
INCLUDES FIRST PARTITION WHEN PRUNING


PROBLEM
-------

TO_DAYS()/TO_SECONDS() can return NULL for invalid dates which 
was stored in the first partition ,therefore the first partition 
was always included for the scan when range was specified.


FIX
---

The fix is a small optimization which we have included ,which will
prune the scanning of NULL/first partition if the dates specified 
in the range are valid and in the same year and month . TO_SECONDS()
function is not supported in 5.1 so removed it from the fix and test
scripts for mysql-5.1 version.
This commit is contained in:
Aditya A 2013-01-11 16:27:37 +05:30
parent 8b41f491c8
commit 21bdf21380
1 changed files with 38 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

38
sql/sql_partition.cc
View file

@ -6793,6 +6793,9 @@ int get_part_iter_for_interval_via_mapping(partition_info *part_info,
get_endpoint_func UNINIT_VAR(get_endpoint);
bool can_match_multiple_values; /* is not '=' */
uint field_len= field->pack_length_in_rec();
MYSQL_TIME start_date;
bool check_zero_dates= false;
bool zero_in_start_date= true;
part_iter->ret_null_part= part_iter->ret_null_part_orig= FALSE;
if (part_info->part_type == RANGE_PARTITION)
@ -6844,6 +6847,7 @@ int get_part_iter_for_interval_via_mapping(partition_info *part_info,
{
/* col is NOT NULL, but F(col) can return NULL, add NULL partition */
part_iter->ret_null_part= part_iter->ret_null_part_orig= TRUE;
check_zero_dates= true;
}
}
@ -6887,6 +6891,19 @@ int get_part_iter_for_interval_via_mapping(partition_info *part_info,
return 1;
}
part_iter->part_nums.cur= part_iter->part_nums.start;
if (check_zero_dates && !part_info->part_expr->null_value)
{
if (!(flags & NO_MAX_RANGE) &&
(field->type() == MYSQL_TYPE_DATE ||
field->type() == MYSQL_TYPE_DATETIME))
{
/* Monotonic, but return NULL for dates with zeros in month/day. */
zero_in_start_date= field->get_date(&start_date, 0);
DBUG_PRINT("info", ("zero start %u %04d-%02d-%02d",
zero_in_start_date, start_date.year,
start_date.month, start_date.day));
}
}
if (part_iter->part_nums.start == max_endpoint_val)
return 0; /* No partitions */
}
@ -6900,6 +6917,27 @@ int get_part_iter_for_interval_via_mapping(partition_info *part_info,
store_key_image_to_rec(field, max_value, field_len);
bool include_endp= !test(flags & NEAR_MAX);
part_iter->part_nums.end= get_endpoint(part_info, 0, include_endp);
if (check_zero_dates &&
!zero_in_start_date &&
!part_info->part_expr->null_value)
{
MYSQL_TIME end_date;
bool zero_in_end_date= field->get_date(&end_date, 0);
/*
This is an optimization for TO_DAYS() to avoid scanning the NULL
partition for ranges that cannot include a date with 0 as
month/day.
*/
DBUG_PRINT("info", ("zero end %u %04d-%02d-%02d",
zero_in_end_date,
end_date.year, end_date.month, end_date.day));
DBUG_ASSERT(!memcmp(((Item_func*) part_info->part_expr)->func_name(),
"to_days", 7));
if (!zero_in_end_date &&
start_date.month == end_date.month &&
start_date.year == end_date.year)
part_iter->ret_null_part= part_iter->ret_null_part_orig= false;
}
if (part_iter->part_nums.start >= part_iter->part_nums.end &&
!part_iter->ret_null_part)
return 0; /* No partitions */