MDEV-27106 added REMOTE_TABLE, REMOTE_DATABASE, REMOTE_SERVER spider
table options. In this commit, we add all remaining options for table
params that are not marked to be deprecated.
All these options are parsed as strings from sql statements and have
string values at the sql level, so that we can determine whether it is
specified by checking its nullness.
The string values are further parsed by Spider into their actual types
in the SPIDER_SHARE, including string list, bounded nonnegative int,
bounded nonnegative int list, nonnegative longlong, boolean, and key
hints. Except for string lists, all other types are validated during
this parsing process.
Most of the options are backward compatible, i.e. they accept any
values that is accepted by there corresponding param parser. The only
exception is the index hint IDX which corresponds to the idxNNN param
name. For example,
'idx000 "f PRIMARY", idx001 "u k1"'
translates to
IDX="f PRIMARY u k1".
We include a test with all options specified, and tests involving
spider table options of all actual types.
Any table options, if present, will cause comments to be ignored with
a warning. The warning can be disabled by setting a new spider
global/session system variable spider_suppress_comment_ignored_warning
to 1.
Another global/session variable introduced is spider_ignore_comments,
which if set to 1, will cause COMMENT and CONNECTION strings to be
ignored unconditionally, whether or not table options are specified.
MDEV-28856 Spider: Tests, documentation, small fixes and cleanups
Removed some redundant hint related string literals from
spd_db_conn.cc
Clean up SPIDER_PARAM_*_[CHAR]LEN[S]
Adding tests covering monitoring_kind=2. What it does is that it reads
from mysql.spider_link_mon_servers with matching db_name, table_name,
link_id, and does not do anything about that...
How monitoring_* can be useful: in the deprecated spider high
availability feature, when one remote fails, spider will try another
remote, which apparently makes use of these table parameters.
A test covering the query_cache_sync table param. Some further tests
on some spider table params.
Wrapper should be case insensitive.
Code documentation on spider priority binary tree.
Add an assertion that static_key_cardinality is always -1. All tests
pass still
Also, spider/bugfix.mdev_29676, when enabled after MDEV-29525 is
pushed will fail because we have not --recorded the result. But the
failure will only emerge when working on MDEV-31138 where we manually
re-enable this test, so let's worry about that then.
MDEV-31586 Make the MDEV-31463 test more fitting and stable
The original test in the report of MDEV-31463 is contrived and
nondeterministic, causing MDEV-31586. We update the test to make it
more directly addresses the underlying cause of MDEV-31463, namely
errors from queries sent to the data node not consumed when trying to
set lock wait timeout. This is achieved through the debug sync
facility.
MDEV-29502 Fix some issues with spider direct aggregate
The direct aggregate mechanism sems to be only intended to work when
otherwise a full table scan query will be executed from the spider
node and the aggregation done at the spider node too. Typically this
happens in sub_select(). In the test spider.direct_aggregate_part
direct aggregate allows to send COUNT statements directly to the data
nodes and adds up the results at the spider node, instead of iterating
over the rows one by one at the spider node.
By contrast, the group by handler (GBH) typically sends aggregated
queries directly to data nodes, in which case DA does not improve the
situation here.
That is why we should fix it by disabling DA when GBH is used.
There are other reasons supporting this change. First, the creation of
GBH results in a call to change_to_use_tmp_fields() (as opposed to
setup_copy_fields()) which causes the spider DA function
spider_db_fetch_for_item_sum_funcs() to work on wrong items. Second,
the spider DA function only calls direct_add() on the items, and the
follow-up add() needs to be called by the sql layer code. In
do_select(), after executing the query with the GBH, it seems that the
required add() would not necessarily be called.
Disabling DA when GBH is used does fix the bug. There are a few
other things included in this commit to improve the situation with
spider DA:
1. Add a session variable that allows user to disable DA completely,
this will help as a temporary measure if/when further bugs with DA
emerge.
2. Move the increment of direct_aggregate_count to the spider DA
function. Currently this is done in rather bizarre and random
locations.
3. Fix the spider_db_mbase_row creation so that the last of its row
field (sentinel) is NULL. The code is already doing a null check, but
somehow the sentinel field is on an invalid address, causing the
segfaults. With a correct implementation of the row creation, we can
avoid such segfaults.
MDEV-31117 clean up spider connection info parsing
Spider connection string is a comma-separated parameter definitions,
where each definition is of the form "<param_title> <param_value>",
where <param_value> is quote delimited on both ends, with backslashes
acting as an escaping prefix.
The code however treated param title the same way as param value when
assigning, and have nonsensical fields like delim_title_len and
delim_title. We remove these.
We also clean up the spider comment connection string parsing,
including:
- Factoring out some code from the parsing function
- Rewriting the struct `st_spider_param_string_parse`, including
replacing its messy methods with cleaner ones
- And any necessary changes caused by the above changes
Fix spider init bugs (MDEV-22979, MDEV-27233, MDEV-28218) while
preventing regression on old ones (MDEV-30370, MDEV-29904)
Two things are changed:
First, Spider initialisation is made fully synchronous, i.e. it no
longer happens in a background thread. Adapted from the original fix
by nayuta for MDEV-27233. This change itself would cause failure when
spider is initialised early, by plugin-load-add, due to dependency on
Aria and udf function creation, which are fixed in the second and
third parts below. Requires SQL Service, thus porting earlier versions
requires MDEV-27595
Second, if spider is initialised before udf_init(), create udf by
inserting into `mysql.func`, otherwise do it by `CREATE FUNCTION` as
usual. This change may be generalised in MDEV-31401.
Also factor out some clean-up queries from deinit_spider.inc for use
of spider init tests.
A minor caveat is that early spider initialisation will fail if the
server is bootstrapped for the first time, due to missing `mysql`
database which needs to be created by the bootstrap script.
Removing procedures that were created and dropped during init.
This also fixes a race condition where mtr test with
plugin-load-add=ha_spider.so causes post test check to fail as it
expects the procedures to still be there.
