Deprecate the server variable spider_internal_offset and the corresponding
table parameters "ios" and "internal_offset".
We believe this variable is not much use to users, therefore decided to
deprecate it.
Reviewed-by: Nayuta Yanagisawa <nayuta.yanagisawa@hey.com>
The variables, spider_crd_mode and spider_sts_mode, specify the
ways to fetch statistics from data nodes.
Using the SHOW command seems to work for any cases. Thus, we deprecate
the variables.
The variable spider_internal_limit is for specifying the number of
records acquired by Spider from each remote server.
There seems not to be much use of the variable. Thus, we deprecate it
and the corresponding table options.
Reviewed-by: Nayuta Yanagisawa <nayuta.yanagisawa@hey.com>
Creating a temporary table with Spider is non-sense because a Spider
table cannot hold any physical data and it requires an additional
effort to manage even if it is configured correctly.
Set HTON_TEMPORARY_NOT_SUPPORTED to spider_hton->flags.
Reviewed-by: nayuta.yanagisawa@hey.com
Co-authored-by: d8sk4ueun@gmail.com
"#ifdef WITH_PARTITION_STORAGE_ENGINE ... #endif" appears frequently
in the Spider code base. However, there is no need to maintain such
ifdefs because Spider is disabled if the partitioning engine is disabled.
Deprecate the plugin variable spider_use_handler and the corresponding
table parameters "uhd" and "use_handler".
Passing a Handler statement to data nodes, without converting it to
SQL sometimes, might improve the performance, while this introduces
some complication to the implementation.
In the first place, only a few people use Handler statements and the
performance gain seems not to be very significant. Further, setting
spider_use_handler > 0 disables the GROUP BY handler. So, we decided
to deprecate the variable.
Remove the dead-code, in Spider, which is related to the Spider's
Oracle OCI support. The code has been disabled for a long time and
it is unlikely that the code will be enabled.
Remove the dead-code, in Spider, which is related to the Spider's
HandlerSocket support. The code has been disabled for a long time
and it is unlikely that the code will be enabled.
We introduce engine-defined attributes to specify remote data nodes.
The engine attributes do not cover all the existing DSN parameters
because most of them need not be specified at the table level.
We introduce the following three attributes: REMOTE_SERVER,
REMOTE_DATABASE, REMOTE_TABLE.
One cannot specify both DSN parameter, in COMMENT or CONNECT, and
engine-defined attribute that are for the same SPIDER_SHARE attribute.
For example, Spider returns an error if both COMMENT='table "t1"'
and REMOTE_TABLE="t2" are specified for a single Spider table or
a single partition in a Spider table.
The commit e954d9de gave different lifetime to wide_share and
partition_handler_share. This introduced the possibility that
partition_handler_share could be accessed even after it was freed.
We stop sharing partitoiin_handler_share and make it belong to
a single wide_handler to fix the problem.
This change removed 68 explict strlen() calls from the code.
The following renames was done to ensure we don't use the old names
when merging code from earlier releases, as using the new variables
for print function could result in crashes:
- charset->csname renamed to charset->cs_name
- charset->name renamed to charset->coll_name
Almost everything where mechanical changes except:
- Changed to use the new Protocol::store(LEX_CSTRING..) when possible
- Changed to use field->store(LEX_CSTRING*, CHARSET_INFO*) when possible
- Changed to use String->append(LEX_CSTRING&) when possible
Other things:
- There where compiler issues with ensuring that all character set names
points to the same string: gcc doesn't allow one to use integer constants
when defining global structures (constant char * pointers works fine).
To get around this, I declared defines for each character set name
length.
The reason for the change is that neither clang or gcc can do efficient
code when several bit fields are change at the same time or when copying
one or more bits between identical bit fields.
Updated bits explicitely with & and | is MUCH more efficient than what
current compilers can do.
Added back variable 'with_subquery' to Item class as a bit field.
This made the code shorter, faster (removed some virtual methods,
less code to create an initialized item etc) and made many Item's 7 bytes
smaller.
This is the last set of my patches the decreases the size of Item.
Some examples from gdb:
sizeof(Item): 144 -> 120
sizeof(Item_func) 208 -> 184
sizeof(Item_sum_max) 368 -> 344
The name of the table sent as an argument to the handler::init() has the
database name in front of it. So we should use
table_share->table_name.length.
Replace
* select_lex::offset_limit
* select_lex::select_limit
* select_lex::explicit_limit
with select_lex::Lex_select_limit
The Lex_select_limit already existed with the same elements and was used in
by the yacc parser.
This commit is in preparation for FETCH FIRST implementation, as it
simplifies a lot of the code.
Additionally, the parser is simplified by making use of the stack to
return Lex_select_limit objects.
Cleanup of init_query() too. Removes explicit_limit= 0 as it's done a bit later
in init_select() with limit_params.empty()
