- Initialize variables that could be used uninitialized
- Added extra end space to DbugStringItemTypeValue to get rid of warnings
from c_ptr()
- Session_sysvars_tracker::update() accessed unitialized memory if called
with NULL value.
- get_schema_stat_record() accessed unitialized memory if HA_KEY_LONG_HASH
was used
- parse_vcol_defs() accessed random memory for tables without keys.
cmake -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_BUILD_TYPE=Debug
Maintainer mode makes all warnings errors. This patch fix warnings. Mostly about
deprecated `register` keyword.
Too much warnings came from Mroonga and I gave up on it.
This patch includes:
- MDEV-19639 sql_mode=ORACLE: Wrong SHOW PROCEDURE output for sysvar:=expr
- MDEV-19640 Wrong SHOW PROCEDURE output for SET GLOBAL sysvar1=expr, sysvar2=expr
- Preparatory refactoring for MySQL WL#4179
Detailed change list:
1. Changing sp_create_assignment_lex() to accept the position
in the exact query buffer instead of a "bool no_lookahead".
This actually fixes MDEV-19639.
In the previous reduction sp_create_assignment_lex() was
called too late, when the parser went far the from beginning
of the statement, so only a part of the statement got into
sp_instr_stmt.
2. Generating "SET" or "SET GLOBAL" inside sp_create_assignment_instr()
depending on the option type.
This fixes MDEV-19640.
In the previous reduction the code passed (through no_lookahead)
the position of the
word GLOBAL inside sp_create_assignment_lex(), which
worked only for the left-most assignment.
3. Fixing the affected rules to use:
- ident_cli instead of ident
- ident_cli_set_usual_case instead of ident_set_usual_case
4. Changing the input parameter in:
- LEX::set_system_variable()
- LEX::call_statement_start()
- LEX::set_variable()
from just LEX_CSTRING to Lex_ident_sys_st for stricter data type constrol:
to make sure that noone passes an ident_cli
(a fragment of the original query in the client character set)
instead of server-side identifier
(utf8 identifier allocated on THD when needed).
5. Adding Lex_ident_sys() in places where the affected functions are called.
6. Moving all calls of sp_create_assignment_lex() to the places
just before parsing set_expr_or_default.
This makes the grammar clearer, because
sp_create_assignment_lex() and sp_create_assignment_instr()
now stay near each other, so the balance of LEX's push/pop
can be read easier.
This will also help to WL#4179.
7. Adding class sp_lex_set_var
Moving the initialization code from
sp_create_assignment_lex() to the constructor of sp_lex_set_var.
This will also help to WL#4179.
8. Moving a part of the "set" grammar rule into a separate
rule "set_param".
This makes the grammar easier to read and removes
one shift/reduce conflict.
This patch complements the patch that fixes bug MDEV-18479.
This patch takes care of possible overflow when calculating the
estimated number of rows in a materialized derived table / view.
query with VALUES()
A table value constructor can be used in all contexts where a select
can be used. In particular an ORDER BY clause or a LIMIT clause or both
of them can be attached to a table value constructor to produce a new
query. Unfortunately execution of such queries was not supported.
This patch fixes the problem.
Only take LOCK_plugin for plugin system variables.
Reverted optimisation that was originally done for session tracker: it
makes much less sense now. Specifically only if connections would want to
track plugin session variables changes and these changes would actually
happen frequently. If this ever becomes an issue, there're much better
ways to optimise this workload.
Part of MDEV-14984 - regression in connect performance
This patch corrects the patch for MDEV-19324. The latter did not
work properly in the cases when the transformation
(SELECT ... ORDER BY ...) LIMIT ... =>
SELECT ... ORDER BY ... LIMIT ...
was applied to the operands of a set operation.
If a select query was of the form (SELECT ... ORDER BY ...) LIMIT ...
then in most cases it returned incorrect result. It happened because
SELECT ... ORDER BY ... was wrapped into a select with materialized
derived table:
SELECT ... ORDER BY ... =>
SELECT * FROM (SELECT ... ORDER BY ...) dt.
Yet for any materialized derived table ORDER BY without LIMIT is ignored.
This patch resolves the problem by the conversion
(SELECT ... ORDER BY ...) LIMIT ... =>
SELECT ... ORDER BY ... LIMIT ...
at the parser stage.
Similarly
((SELECT ... UNION ...) ORDER BY ...) LIMIT ...
is converted to
(SELECT ... UNION ...) ORDER BY ... LIMIT ...
This conversion optimizes execution of the query because the result of
(SELECT ... UNION ...) ORDER BY ... is not materialized into a temporary
table anymore.
A sequence of <digits>e<mbhead><mbtail>, e.g.:
SELECT 123eXYzzz FROM t1;
was not scanned correctly (where XY is a multi-byte character).
The multi-byte head byte X was appended to 123e separately from
the multi-byte tail byte Y, so a pointer to "Yzzz" was passed
into scan_ident_start(), which failed on a bad multi-byte sequence.
After this change, scan_ident_start() gets a pointer to "XYzzz",
so it correctly sees the whole multi-byte character.
When pushing a condition from HAVING into WHERE the function
st_select_lex::pushdown_from_having_into_where() transforms column
references in the pushed condition then performs cleanup of
items of the condition and finally calls fix_fields() for the condition
items. The cleanup is performed by a call of the method walk() with
cleanup_processor as the first parameter. Unfortunately this sequence
of calls does not work if the condition contains cached items, because
fix_fields() cannot go through Item_cache items and this leaves
underlying items unfixed.
The solution of this problem used in this patch is just does not allow
to process Item_cache objects when performing cleanup of the pushed
condition. In order to let the traversal procedure walk() not to process
Item_cache objects the third parameter of the used call of walk()
is set to a fictitious pointer (void *) 1. And Item_cache::walk() is
changed to prevent any action when it gets such value as the third
parameter.
A syntax error was reported for any INSERT statement with explicit
partition selection it if i used a column list.
Fixed by saving the parsing place before parsing the clause for explicit
partition selection and restoring it when the clause has been parsed.
This bug is caused by pushdown from HAVING into WHERE.
It appears because condition that is pushed wasn't fixed.
It is also discovered that condition pushdown from HAVING into
WHERE is done wrong. There is no need to build clones for some
conditions that can be pushed. They can be simply moved from HAVING
into WHERE without cloning.
build_pushable_cond_for_having_pushdown(),
remove_pushed_top_conjuncts_for_having() methods are changed.
It is found that there is no transformation made for fields of
pushed condition.
field_transformer_for_having_pushdown transformer is added.
New tests are added. Some comments are changed.
