The existing syntax for renaming a column uses "ALTER TABLE ... CHANGE"
command. This requires full column specification to rename the column.
This patch adds new syntax "ALTER TABLE ... RENAME COLUMN", which do not
expect users to provide full column specification. It means that the new
syntax would pick in-place or copy algorithm in the same way as that of
existing "ALTER TABLE ... CHANGE" command. The existing syntax
"ALTER TABLE ... CHANGE" will continue to work.
Syntax changes
==============
ALTER TABLE tbl_name
[alter_specification [, alter_specification] ...]
[partition_options]
Following is a new <alter_specification> added:
| RENAME COLUMN <oldname> TO <newname>
Where <oldname> and <newname> are identifiers for old name and new
name of the column.
Related to: WL#10761
Rewriting GRANT/REVOKE grammar to use more bison stack and use Sql_cmd_ style
1. Removing a few members from LEX:
- uint grant, grant_to_col, which_columns
- List<LEX_COLUMN> columns
- bool all_privileges
2. Adding classes Grand_object_name, Lex_grant_object_name
3. Adding classes Grand_privilege, Lex_grand_privilege
4. Adding struct Lex_column_list_privilege_st, class Lex_column_list_privilege
5. Rewriting the GRANT/REVOKE grammar to use new classes and pass them through
bison stack (rather than directly access LEX members)
6. Adding classes Sql_cmd_grant* and Sql_cmd_revoke*,
changing GRANT/REVOKE to use LEX::m_sql_cmd.
7. Adding the "sp_handler" grammar rule and removing some duplicate grammar
for GRANT/REVOKE for different kinds of SP objects.
8. Adding a new rule comma_separated_ident_list, reusing it in:
- with_column_list
- colum_list_privilege
with condition_pushdown_from_having
This bug could manifest itself for queries with GROUP BY and HAVING clauses
when the HAVING clause was a conjunctive condition that depended
exclusively on grouping fields and at least one conjunct contained an
equality of the form fld=sq where fld is a grouping field and sq is a
constant subquery.
In this case the optimizer tries to perform a pushdown of the HAVING
condition into WHERE. To construct the pushable condition the optimizer
first transforms all multiple equalities in HAVING into simple equalities.
This has to be done for a proper processing of the pushed conditions
in WHERE. The multiple equalities at all AND/OR levels must be converted
to simple equalities because any multiple equality may refer to a multiple
equality at the upper level.
Before this patch the conversion was performed like this:
multiple_equality(x,f1,...,fn) => x=f1 and ... and x=fn.
When an equality item for x=fi was constructed both the items for x and fi
were cloned. If x happened to be a constant subquery that could not be
cloned the conversion failed. If the conversions of multiple equalities
previously performed had succeeded then the whole condition became in an
inconsistent state that could cause different failures.
The solution provided by the patch is:
1. to use a different conversion rule if x is a constant
multiple_equality(x,f1,...,fn) => f1=x and f2=f1 and ... and fn=f1
2. not to clone x if it's a constant.
Such conversions cannot fail and besides the result of the conversion
preserves the equivalence of f1,...,fn that can be used for other
optimizations.
This patch also made sure that expensive predicates are not pushed from
HAVING to WHERE.
(Variant #2 of the patch, which keeps the sp_head object inside the
MEM_ROOT that sp_head object owns)
(10.3 requires extra work due to sp_package, will commit a separate
patch for it)
sp_head::operator new() and operator delete() were dereferencing sp_head*
pointers to memory that didn't hold a valid sp_head object (it was
not created/already destroyed).
This caused UBSan to crash when looking up type information.
Fixed by providing static sp_head::create() and sp_head::destroy() methods.
(Variant #2 of the patch, which keeps the sp_head object inside the
MEM_ROOT that sp_head object owns)
(10.3 version of the fix, with handling for class sp_package)
sp_head::operator new() and operator delete() were dereferencing sp_head*
pointers to memory that didn't hold a valid sp_head object (it was
not created/already destroyed).
This caused UBSan to crash when looking up type information.
Fixed by providing static sp_head::create() and sp_head::destroy() methods.
Set read_set bitmap for view from the JOIN::all_fields list instead of JOIN::fields_list
as split_sum_func would have added items to the all_fields list.
Add support of referential constraints directly in column defininions:
create table t1 (id1 int primary key);
create table t2 (id2 int references t1(id1));
Referenced field name can be omitted if equal to foreign field name:
create table t1 (id int primary key);
create table t2 (id int references t1);
Until 10.5 this syntax was understood by the parser but was silently
ignored.
In case of generated columns this syntax is disabled at parser level
by ER_PARSE_ERROR. Note that separate FOREIGN KEY clause for generated
columns is disabled at storage engine level.
On order to unify the two *.yy files easier,
this patch collects all different rules to the end of *.yy files,
so the rule section looks like this:
%%
common rules
different rules
Adding:
- new class sp_expr_lex
- new grammar rule expr_lex, which includes both reset_lex()
and its corresponding restore_lex()
Also:
- Moving a few methods from LEX to sp_expr_lex.
- Moving the code from *.yy to new method sp_expr_lex methods
sp_repeat_loop_finalize() and sp_if_expr().
This change makes it easier to edit the related grammar
(and makes it easier to unify sql_yacc.yy and sql_yacc_ora.yy later).
* Explicit STARTS syntax
* SHOW CREATE
* Default STARTS rounding depending on INTERVAL type
* Warn when STARTS timestamp is later than query time
* Fix uninitialized Lex->create_last_non_select_table under
mysql_unpack_partition()
Default STARTS rounding depending on INTERVAL type
If STARTS clause is omitted, default one is assigned with value
derived from query timestamp. The rounding is done on STARTS value
depending on INTERVAL type:
SECOND: no rounding is done;
MINUTE: timestamp seconds is set to 0;
HOUR: timestamp seconds and minutes are set to 0;
DAY, WEEK, MONTH and YEAR: timestamp seconds, minutes and hours are
set to 0 (the date of rotation is kept as current date).
In order to:
- unify sql_yacc.yy and sql_yacc_ora.yy easier
- move more functionality from the parser to Type_handler
(so plugins can override the behavior)
this patch:
- removes rules sp_param_field_type_string and sp_param_field_type
from sql_yacc_ora.yy
- adds a new virtial method Type_handler::Column_definition_set_attributes()
LEX::parsed_select_expr_cont(): Replace a condition with an
assertion DBUG_ASSERT(!s2->next_select()), and always
initialize sel1=s2, because all subsequent code paths will
assign to sel1->first_nested.
This was flagged by GCC reporting -Wmaybe-uninitialized
for the statement last->link_neighbour(sel1).
Shift-Reduce conflicts prevented parsing some queries with subqueries that
used set operations when the subqueries occurred in expressions or in IN
predicands.
The grammar rules for query expression were transformed in order to avoid
these conflicts. New grammar rules employ an idea taken from MySQL 8.0.
Pruning fix for SYSTEM_TIME INTERVAL partitioning.
Allocating one more element in range_int_array for CURRENT partition
is required for RANGE pruning to work correctly
(get_partition_id_range_for_endpoint()).
SYSTEM_TYPE partitioning: COLUMN properties removed. Partitioning is
now pure RANGE based on UNIX_TIMESTAMP(row_end).
DECIMAL type is now allowed as RANGE partitioning, we can partition by
UNIX_TIMESTAMP() (but not for DATETIME which depends on local timezone
of course).
With --skip-debug-assert, DBUG_ASSERT(false) will allow execution to
continue. Hence, we will need /* fall through */ after them.
Some DBUG_ASSERT(0) were replaced by break; when the switch () statement
was followed by DBUG_ASSERT(0).
