In some cases "SHOW PROCESSLIST" could show "Reset for next command"
as State, even if the previous query had finished properly.
Fixed by clearing State after end of command and also setting the State
for the "Connect" command.
Other things:
- Changed usage of 'thd->set_command(COM_SLEEP)' to
'thd->mark_connection_idle()'.
- Changed thread_state_info() to return "" instead of NULL. This is
just a safety measurement and in line with the logic of the
rest of the function.
MDEV-32441 SENT_ROWS shows random wrong values when stored function
is selected.
MDEV-32281 EXAMINED_ROWS is not populated in
information_schema.processlist upon SELECT.
Added ROWS_SENT to information_schema.processlist
This is to have the same information as Percona server (SENT_ROWS)
To ensure that information_schema.processlist has correct values for
sent_rows and examined_rows I introduced two new variables to hold the
total counts so far. This was needed as stored functions and stored
procedures will reset the normal counters to be able to count rows for
each statement individually for slow query log.
Other things:
- Selects with functions shows in processlist the total examined_rows
and sent_rows by the main statement and all functions.
- Stored procedures shows in processlist examined_rows and sent_rows
per stored procedure statement.
- Fixed some double accounting for sent_rows and examined_rows.
- HANDLER operations now also supports send_rows and examined_rows.
- Display sizes for MEMORY_USED, MAX_MEMORY_USED, EXAMINED_ROWS and
QUERY_ID in information_schema.processlist changed to 10 characters.
- EXAMINED_ROWS and SENT_ROWS changed to bigint.
- INSERT RETURNING and DELETE RETURNING now updates SENT_ROWS.
- As thd is always up to date with examined_rows, we do not need
to handle examined row counting for unions or filesort.
- I renamed SORT_INFO::examined_rows to m_examined_rows to ensure that
we don't get bugs in merges that tries to use examined_rows.
- Removed calls of type "thd->set_examined_row_count(0)" as they are
not needed anymore.
- Removed JOIN::join_examined_rows
- Removed not used functions:
THD::set_examined_row_count()
- Made inline some functions that where called for each row.
standard table KEY_COLUMN_USAGE should only show keys where
a user has some privileges on every column of the key
standard table TABLE_CONSTRAINTS should show tables where
a user has any non-SELECT privilege on the table or on any column
of the table
standard table REFERENTIAL_CONSTRAINTS is defined in terms of
TABLE_CONSTRAINTS, so the same rule applies. If the user
has no rights to see the REFERENCED_TABLE_NAME value, it should be NULL
SHOW INDEX (and STATISTICS table) is non-standard, but it seems
reasonable to use the same logic as for KEY_COLUMN_USAGE.
The MDEV-29693 conflict resolution is from Monty, as well as is
a bug fix where ANALYZE TABLE wrongly built histograms for
single-column PRIMARY KEY.
Also includes a fix for safe_malloc error reporting.
Other things:
- Copied main.log_slow from 10.4 to avoid mtr issue
Disabled test:
- spider/bugfix.mdev_27239 because we started to get
+Error 1429 Unable to connect to foreign data source: localhost
-Error 1158 Got an error reading communication packets
- main.delayed
- Bug#54332 Deadlock with two connections doing LOCK TABLE+INSERT DELAYED
This part is disabled for now as it fails randomly with different
warnings/errors (no corruption).
Problem:
Under terms of MDEV-27490, we'll update Unicode version used
to compare identifiers to 14.0.0. Unlike in the old Unicode version,
in the new version a string can grow during lower-case. We cannot
perform check_db_name() inplace any more.
Change summary:
- Allocate memory to store lower-cased identifiers in memory root
- Removing check_db_name() performing both in-place lower-casing and validation
at the same time. Splitting it into two separate stages:
* creating a memory-root lower-cased copy of an identifier
(using new MEM_ROOT functions and Query_arena wrapper methods)
* performing validation on a constant string
(using Lex_ident_fs methods)
Implementation details:
- Adding a mysys helper function to allocate lower-cased strings on MEM_ROOT:
lex_string_casedn_root()
and a Query_arena wrappers for it:
make_ident_casedn()
make_ident_opt_casedn()
- Adding a Query_arena method to perform both MEM_ROOT lower-casing and
database name validation at the same time:
to_ident_db_internal_with_error()
This method is very close to the old (pre-11.3) check_db_name(),
but performs lower-casing to a newly allocated MEM_ROOT
memory (instead of performing lower-casing the original string in-place).
- Adding a Table_ident method which additionally handles derived table names:
to_ident_db_internal_with_error()
- Removing the old check_db_name()
Also fixes MDEV-32025 Crashes in MDL_key::mdl_key_init with lower-case-table-names=2
Change overview:
- In changes made in MDEV-31948, MDEV-31982 the code path
which originaly worked only in case of lower-case-table-names==1
also started to work in case of lower-case-table-names==2 in a mistake.
Restoring the original check_db_name() compatible behavior
(but without re-using check_db_name() itself).
- MDEV-31978 erroneously added a wrong DBUG_ASSERT. Removing.
Details:
- In mysql_change_db() the database name should be lower-cased only
in case of lower_case_table_names==1. It should not be lower-cased
for lower_case_table_names==2. The problem was caused by MDEV-31948.
The new code version restored the pre-MDEV-31948 behavior, which
used check_db_name() behavior.
- Passing lower_case_table_names==1 instead of just lower_case_table_names
to the "casedn" parameter to DBNameBuffer constructor in sql_parse.cc
The database name should not be lower-cased for lower_case_table_names==2.
This restores pre-MDEV-31982 behavioir which used check_db_name() here.
- Adding a new data type Lex_ident_db_normalized, it stores database
names which are both checked and normalized to lower case
in case lower_case_table_names==1 and lower_case_table_names==2.
- Changing the data type for the "db" parameter to Lex_ident_db_normalized in
lock_schema_name(), lock_db_routines(), find_db_tables_and_rm_known_files().
This is to avoid incorrectly passing a non-normalized name in the future.
- Restoring the database name normalization in mysql_create_db_internal()
and mysql_rm_db_internal() before calling lock_schema_name().
The problem was caused MDEV-31982.
- Adding database name normalization in mysql_alter_db_internal()
and mysql_upgrade_db(). This fixes MDEV-32026.
- Removing a wrong assert in Create_sp_func::create_with_db() was incorrect:
DBUG_ASSERT(Lex_ident_fs(*db).ok_for_lower_case_names());
The database name comes to here checked, but not normalized
to lower case with lower-case-table-names=2.
The assert was erroneously added by MDEV-31978.
- Recording lowercase_tables2.results and lowercase_tables4.results
according to
MDEV-29446 Change SHOW CREATE TABLE to display default collations
These tests are skipped on buildbot on all platforms, so this change
was forgotten in the patch for MDEV-29446.
- Changing the data type of the global variable any_db from
LEX_CSTRING to Lex_ident_db
- Removing the dependency on system_charset_info from
Lex_ident_fs::check_body(), using my_charset_utf8mb3_general_ci directly,
because system_charset_info is initialized much later than any_db.
system_charset_info cannot be changed dynamically any way.
- Removing the unsed old code from Lex_ident_fs::check_body().
This code was last used in MySQL-4.0 and won't be used in the future.
- Adding a new class Lex_ident_db, to store normalized database names:
lower-cased if lower-case-table-name says so,
and checked to be a valid database name using Lex_ident_fs::check_db_name()
- Reusing the new class in parameters to functions:
prepare_db_action()
mysql_create_db()
mysql_alter_db()
mysql_rm_db()
mysql_upgrade_db()
This change removed two old-style check_db_name() calls.
- Adding a class Lex_ident_fs, to store identifiers for on-disk
database objects, such as databases, tables, triggers.
- Moving the validation code from check_db_name()
to non-modifying methods in Lex_ident_fs:
Lex_ident_fs::check_body()
Lex_ident_fs::check_db_name()
Adding a new method Lex_ident_fs::check_db_name_with_error(),
which performs validation and raises an error on validation failure.
Unlike the old function check_db_name(), the new class Lex_ident_fs
does not lower-case the identifier during the validation.
Lower-casing must be done before calling Lex_ident_fs validation methods.
- Adding a low level helper template class CharBuffer which can:
* store exact or lower-cased strings with a short fixed maximum length
* return the value as a LEX_CSTRING efficiently
- Adding a helper template class DBNameBuffer (deriving from CharBuffer), to
allocate optionally lower-cased database identifiers on stack when relevant.
Useful for temporary values which don't need to be allocated on MEM_ROOT.
- Using DBNameBuffer in mysql_change_db()
- Using DBNameBuffer in show_create_db()
Before this patch, the code in Item_field::print() used
this convention (described in sql_explain.h:ExplainDataStructureLifetime):
- By default, the table that Item_field refers to is accessible.
- ANALYZE and SHOW {EXPLAIN|ANALYZE} may print Items after some
temporary tables have been dropped. They use
QT_DONT_ACCESS_TMP_TABLES flag. When it is ON, Item_field::print
will not access the table it refers to, if it is a temp.table
The bug was that EXPLAIN statement also may compute subqueries (depending
on subquery context and @@expensive_subquery_limit setting). After the
computation, the subquery calls JOIN::cleanup(true) which drops some of
its temporary tables. Calling Item_field::print() that refer to such table
will cause an access to free'd memory.
In this patch, we take into account that query optimization can compute
a subquery and discard its temporary tables. Item_field::print() now
assumes that any temporary table might have already been dropped.
This means QT_DONT_ACCESS_TMP_TABLES flag is not needed - we imply it is
always present.
But we also make one exception: derived tables are not freed in
JOIN::cleanup() call. They are freed later in close_thread_tables(),
at the same time when regular tables are closed.
Because of that, Item_field::print may assume that temp.tables
representing derived tables are available.
Initial patch by: Rex Jonston
Reviewed by: Monty <monty@mariadb.org>
- Pre-open temporary table on sequence creation.
- Without this patch, if rename alter is done on the temporary sequence,
and after that `create replace`, since table is not preopened and
alter rename marked the table as reopen, and such table is deleted in
the `find_temporary_table()` leaving the share without the table, that
causes `show tables` to fail
- Closes PR #2685
- Reviewer: <serg@mariadb.com>
