1. Adding the forgotten "SET sql_mode=STRICT_ALL_TABLES" into the test.
2. STRICT_ALL_TABLES revealed that CAST(0xFFFFFFFF AS SIGNED),
e.g. with a hex number with 8 hex digits, did not work well.
Fixing Item_func_unsigned::create_tmp_field() and
Item_func_unsigned::create_field_for_create_select() to handle
this corner case.
Introducing a new class Type_holder (used internally in sql_union.cc),
to reuse exactly the same data type attribute aggregation Type_handler API
for hybrid functions and UNION.
This fixes a number of bugs in UNION:
- MDEV-9495 Wrong field type for a UNION of a signed and an unsigned INT expression
- MDEV-9497 UNION and COALESCE produce different field types for DECIMAL+INT
- MDEV-12594 UNION between fixed length double columns does not always preserve scale
- MDEV-12595 UNION converts INT to BIGINT
- MDEV-12599 UNION is not symmetric when mixing INT and CHAR
Details:
- sql_union.cc: Reusing attribute aggregation for UNION.
Adding new methods:
* st_select_lex_unit::join_union_type_handlers()
* st_select_lex_unit::join_union_type_attributes()
* st_select_lex_unit::join_union_item_types()
Removing the old join_types()-based code.
- Changing Type_handler::Item_hybrid_func_fix_attributes()
to accept "name", Type_handler_hybrid_field_type, Type_all_attributes
as three separate parameters instead of a single Item_hybrid_func parameter,
to make it possible to pass both Item_hybrid_func and Type_holder.
- Moving the former special GEOMETRY and ENUM/SET attribute aggregation code
from Item_type_holder::join_types() to
* Type_handler_typelib::Item_hybrid_func_fix_attributes().
* Type_handler_geometry::Item_hybrid_func_fix_attrubutes().
This makes GEOMETRY/ENUM/SET symmetric with all other data types
(from the UNION point of view).
Removing Item_type_holder::join_types() and Item_type_holder::get_full_info().
- Adding new methods into Type_all_attributes:
* Type_all_attributes::set_geometry_type() and
Item_hybrid_func::set_geometry_type().
* Adding Type_all_attributes::get_typelib().
* Adding Type_all_attributes::set_typelib().
- Adding Type_handler_typelib as a common parent for
Type_handler_enum and Type_handler_set, to avoid code duplication: they have
already had two common methods, and we're adding one more shared method.
- Adding Type_all_attributes::set_maybe_null(), as some type handlers
may want to set maybe_null (e.g. Type_handler_geometry) during data type
attribute aggregation.
- Changing Type_geometry_attributes() to accept Type_handler
and Type_all_attributes as two separate parameters, instead
of a single Item parameter, to make it possible to pass Type_holder.
- Adding Item_args::add_argument().
- Moving Item_args::alloc_arguments() from "protected" to "public".
- Moving Item_type_holder::Item_type_holder() from item.cc to item.h, as
now it's very simple.
Btw, this constructor should probably be eventually removed.
It's now used only in sql_show.cc, which could be modified to use
Item_return_decimal (for symmetry with Item_return_xxx created for all
other data types). Or, another option: remove all Item_return_xxx and
use Item_type_holder for all data types instead.
- storage/tokudb/mysql-test/tokudb/r/type_float.result
Recording new results (MDEV-12594).
- mysql-test/r/cte_recursive.result
Recording new results (MDEV-9497)
- mysql-test/r/subselect*.result
Recording new results (MDEV-12595)
- mysql-test/r/metadata.result
Recording new results (MDEV-9495)
- mysql-test/r/temp_table.result
Recording new results (MDEV-12594)
- mysql-test/r/type_float.result
Recording new results (MDEV-12594)
This is a join patch fixing these two bugs:
MDEV-12560 Wrong data type for SELECT NULL UNION SELECT Point(1,1)
MDEV-12665 Hybrid functions do not preserve geometry type
Port of mysql changeset by Georgi Kodinov <Georgi.Kodinov@Oracle.com>:
Bug #34325 : --add-drop-trigger option for mysqldump
Implemented the --add-drop-trigger option to prepend each
CREATE TRIGGER in the dump file with DROP TRIGGER.
The option is off by default. Added a test case.
The usage of windows functions when all tables were optimized away
by min/max optimization were not supported. As result a result,
the queries that used window functions with min/max aggregation
over the whole table returned wrong result sets.
The patch fixed this problem.
The bug happened when the specification of a recursive CTE had
no recursive references at the top level of the specification.
In this case the regular processing of derived table references
of the select containing a non-recursive reference to this
recursive CTE misses handling the specification unit.
At the preparation stage any non-recursive reference to a
recursive CTE must be handled after the preparation of the
specification unit for this CTE. So we have to force this
preparation when regular handling of derived tables does not
do it.
When the rows produced on the current iteration are sent to the
temporary table T of the UNION type created for CTE the rows
that were not there simultaneously are sent to the temporary
table D that contains rows for the next iteration. The test
whether a row was in T checks the return code of writing into T.
If just a HEAP table is used for T then the return code is
HA_ERR_FOUND_DUPP_KEY, but if an ARIA table is used for T then
the return code is HA_ERR_FOUND_DUPP_UNIQUE.
The implementation of select_union_recursive::send_data()
erroneously checked only for the first return code. So if an Aria
table was used for T then all rows produced by the current iteration
went to D and and in most cases D grew with each iteration.
Whether T has reached stabilization is detected by
checking whether D is empty. So as a result, the iterations were
never stopped unless a limit for them was set.
Fixed by checking for both HA_ERR_FOUND_DUPP_KEY and
HA_ERR_FOUND_DUPP_UNIQUE as return codes returned by
the function writing a row into the temporary table T.
In the current code temporary tables we identified and opened before
other tables. CTE tables are identified in the same procedure as
regular tables. When a temporary table and a CTE table have the same
name T any reference to T that is in the scope of the CTE declaration
must be associated with this CTE. Yet it was not done properly.
When a reference to T was found in the scope of the declaration
of CTE T a pointer to this CTE was set in the reference. No check
that the reference had been already associated with a temporary table
was done. As a result, if the temporary table T had been created then
the reference to T was considered simultaneously as reference to the CTE
named T and as a reference to the temporary table named T. This
confused the code that were executed later and caused a crash of
the server.
Now when a table reference is associated with a CTE any previous
association with a temporary table is dropped.
This problem could be easily avoided if the temporary tables were
not identified prematurely.
as reference to CTE named T and
This is a joint patch for:
- MDEV-12426 Add Field::type_handler()
- MDEV-12432 Range optimizer for ENUM and SET does not return "Impossible WHERE" in some case
With the new type handler approach being added to Field, it was easier to fix
MDEV-12432 rather than to reproduce the old ENUM/SET behavior.
The patch does the following:
1. Adds Field::type_handler(), according to the task description.
2. Fixes the asymmetry between Fields and Items of ENUM and SET field types.
Field_enum::cmp_type() returned INT_RESULT
Item*::cmp_type() returned STRING_RESULT for ENUM and SET expressions
This asymmetry was originally done for easier coding in the optimizer sources.
However, in 10.1 we moved a lot of code to methods of the class Field:
- test_if_equality_guarantees_uniqueness()
- can_be_substituted_to_equal_item()
- get_equal_const_item()
- can_optimize_keypart_ref()
- can_optimize_hash_join()
- can_optimize_group_min_max()
- can_optimize_range()
- can_optimize_outer_join_table_elimination()
As of 10.2 only a few lines of the code in opt_range.cc, field.cc and field.h
still relayed on the fact that Field_enum::cmp_type() returns INT_RESULT:
- Some asserts in field.cc
- Field_year::get_copy_func()
- Item_func_like::get_mm_leaf()
- Item_bool_func::get_mm_leaf()
These lines have been fixed.
3. Item_bool_func::get_mm_leaf() did not work well for ENUM/SET,
see MDEV-12432. So the ENUM/SET code was rewritten, and the relevant
code in Field_enum::store() and Field_set::store() was fixed to
properly return errors to the caller.
4. The result of Field_decimal::result_type() was changed from REAL_RESULT
to DECIMAL_RESULT. Data type aggregation (e.g. in COALESCE()) is now more
precise for old DECIMAL, because Item::decimal_precision() now goes through
the DECIMAL_RESULT branch. Earlier it went through the REAL_RESULT branch.
Here's what started happening after the patch that fixed
the bug mdev-10454 with query reported for the bug
SELECT * FROM t t1 right JOIN t t2 ON (t2.pk = t1.pk)
WHERE (t2.i, t2.pk) NOT IN ( SELECT t3.i, t3.i FROM t t3, t t4 )
AND t1.c = 'foo';
The patch added an implementation of propagate_equal_fields() for
the class Item_row and thus opened the possibility of equal fields
substitutions.
At the prepare stage after setup_conds() called for WHERE condition
had completed the flag of maybe_null of the Item_row object created
for (t2.i, t2.pk) was set to false, because the maybe_null flags of
both elements were set to false. However the flag of maybe_null for
t1.pk from the ON condition were set to true, because t1 was an inner
table of an outer join.
At the optimization stage the outer join was converted to inner join,
but the maybe_null flags were not corrected and remained the same.
So after the substitution t2.pk/t1.pk. the maybe_null flag for the
row remained false while the maybe_flag for the second element of
the row was true. As a result, when the in-to_exists transformation
was performed for the NOT IN predicate the guards variables were
not created for the elements of the row, but a guard object for
the second element was created. The object were not valid because
it referred to NULL as a guard variable. This ultimately caused
a crash when the expression with the guard was evaluated at the
execution stage.
The patch made sure that the guard objects are not created without
guard variables.
Yet it does not resolve the problem of inconsistent maybe_null flags.
and it might be that the problem will pop op in other pieces of code.
The resolution of this problem is not easy, but the problem should
be resolved in future versions.
Fixing that the server tried to create the old decimal for:
CREATE TABLE t2 AS SELECT old_decimal_field FROM t1
UNION SELECT bigint_field FROM t1;
CREATE TABLE t2 AS SELECT old_decimal_field FROM t1
UNION SELECT mediumint_field FROM t1;
CREATE TABLE t2 AS SELECT year FROM t1
UNION SELECT old_decimal_field FROM t1;
CREATE TABLE t2 AS SELCT COALESCE(old_decimal_field) FROM t1;
Solution:
1. field_types_merge_rules[][] had three MYSQL_TYPE_DECIMAL remainders.
Fixing to MYSQL_TYPE_NEWDECIMAL, like it is done for all other type pairs.
This fixes the above queries with UNION.
2. Convert MYSQL_TYPE_DECIMAL to MYSQL_TYPE_NEWDECIMAL in
Item::tmp_table_field_from_field_type().
This fixed the above query with COALESCE.
3. Adding "new Field_decimal" into Type_handler_olddecimal::make_table_field().
In case if something goes wrong it will crash on assert only in debug builds,
while create the old decimal in release.
Note, this "new Field_decimal" will be needed later anyway,
when we reuse Type_handler::make_table_field() in make_field() in field.cc.
- Adding Type_handler::make_table_field() and moving pieces of the code
from Item::tmp_table_field_from_field_type() to virtual implementations
for various type handlers.
- Adding a new Type_all_attributes, to access to Item's extended
attributes, such as decimal_precision() and geometry_type().
- Adding a new class Record_addr, to pass record related information
to Type_handler methods (ptr, null_ptr and null_bit) as a single structure.
Note, later it will possibly be extended for BIT-alike field purposes,
by adding new members (bit_ptr_arg, bit_ofs_arg).
- Moving the code from Field_new_decimal::create_from_item()
to Type_handler_newdecimal::make_table_field().
- Removing Field_new_decimal() and Field_geom() helper constructor
variants that were used for temporary field creation.
- Adding Item_field::type_handler(), Field::type_handler() and
Field_blob::type_handler() to return correct type handlers for
blob variants, according to Field_blob::packlength.
- Adding Type_handler_blob_common, as a common parent for
Type_handler_tiny_blob, Type_handler_blob, Type_handler_medium_blob
and Type_handler_long_blob.
- Implementing Type_handler_blob_common::Item_hybrid_func_fix_attributes().
It's needed for cases when TEXT variants of different character sets are mixed
in LEAST, GREATEST, CASE and its abreviations (IF, IFNULL, COALESCE), e.g.:
CREATE TABLE t1 (
a TINYTEXT CHARACTER SET latin1,
b TINYTEXT CHARACTER SET utf8
);
CREATE TABLE t2 AS SELECT COALESCE(a,b) FROM t1;
Type handler aggregation returns TINYTEXT as a common data type
for the two columns. But as conversion from latin1 to utf8
happens for "a", the maximum possible length of "a" grows from 255 to 255*3.
Type_handler_blob_common::Item_hybrid_func_fix_attributes() makes sure
to update the blob type handler according to max_length.
- Adding Type_handler::blob_type_handler(uint max_octet_length).
- Adding a few m_type_aggregator_for_result.add() pairs, because
now Item_xxx::type_handler() can return pointers to type_handler_tiny_blob,
type_handler_blob, type_handler_medium_blob, type_handler_long_blob.
Before the patch only type_handler_blob was possible result of type_handler().
- Making type_handler_tiny_blob, type_handler_blob, type_handler_medium_blob,
type_handler_long_blob public.
- Removing the condition in Item_sum_avg::create_tmp_field()
checking Item_sum_avg::result_type() against DECIMAL_RESULT.
Now both REAL_RESULT and DECIMAL_RESULT are symmetrically handled
by tmp_table_field_from_field_type().
- Removing Item_geometry_func::create_field_for_create_select(),
as the inherited version perfectly works.
- Fixing Item_func_as_wkb::field_type() to return MYSQL_TYPE_LONG_BLOB
rather than MYSQL_TYPE_BLOB. It's needed to make sure that
tmp_table_field_from_field_type() creates a LONGBLOB field for AsWKB().
- Fixing Item_func_as_wkt::fix_length_and_dec() to set max_length to
UINT32_MAX rather than MAX_BLOB_WIDTH, to make sure that
tmp_table_field_from_field_type() creates a LONGTEXT field for AsWKT().
- Removing Item_func_set_user_var::create_field_for_create_select(),
as the inherited version works fine.
- Adding Item_func_get_user_var::create_field_for_create_select() to
make sure that "CREATE TABLE t1 AS SELECT @string_user variable"
always creates a field of LONGTEXT/LONGBLOB type.
- Item_func_ifnull::create_field_for_create_select()
behavior has changed. Before the patch it passed set_blob_packflag=false,
which meant to create LONGBLOB for all blob variants.
Now it takes into account max_length, which gives better column
data types for:
CREATE TABLE t2 AS SELECT IFNULL(blob_column1, blob_column2) FROM t1;
- Fixing Item_func_nullif::fix_length_and_dec() to use
set_handler(args[2]->type_handler()) instead of
set_handler_by_field_type(args[2]->field_type()).
This is needed to distinguish between BLOB variants.
- Implementing Item_blob::type_handler(), to make sure to create
proper BLOB field variant, according to max_length, for queries like:
CREATE TABLE t1 AS
SELECT some_blob_field FROM INFORMATION_SCHEMA.SOME_TABLE;
- Fixing Item_field::real_type_handler() to make sure that
the code aggregating fields for UNION gets a proper BLOB
variant type handler from fields.
- Adding a special code into Item_type_holder::make_field_by_type(),
to make sure that after aggregating field types it also properly
takes into account max_length when mixing TEXT variants of different
character sets and chooses a proper TEXT variant:
CREATE TABLE t1 (
a TINYTEXT CHARACTER SET latin1,
b TINYTEXT CHARACTER SET utf8
);
CREATE TABLE t2 AS SELECT a FROM t1 UNION SELECT b FROM t1;
- Adding tests, for better coverage of IFNULL, NULLIF, UNION.
- The fact that tmp_table_field_from_field_type() now takes
into account BLOB variants (instead of always creating LONGBLOB),
tests results for WEIGHT_STRING() and NULLIF() and UNION
have become more precise.
This patch does the following:
1. Adds a new method Type_handler_hybrid_field_type::aggregate_for_min_max()
- For non-traditional data types it uses
type_handler_data->m_type_aggregator_for_result.find_handler()
This allows pluggable data types to define in the future their
own behavior of the result data type detection for LEAST/GREATEST.
Also, this disallows expressions of the GEOMETRY data type
(and its variants such as POINT) to be mixed in with
numeric and temporal data types in LEAST/GREATEST.
- For traditional data types it reproduces the old behavior of
the result data type detection (but not attributes, see below).
2. Adds a new virtual method Type_handler::Item_func_min_max_fix_attributes()
and reuses as much as possible the code that calculates data type attributes
for CASE-alike functions (e.g. CASE..THEN, COALESCE, IF).
As the old code responsible for attributes calculation in the old
implementation of Item_func_min_max::fix_length_and_dec()
was not fully correct, this automatically fixes the following bugs:
- MDEV-12497 Wrong data type for LEAST(latin1_expr, utf8_expr)
The old fix_length_and_dec() calculated max_length before
character set aggregation. Now max_length is calculated after, in
Item_func::count_string_length() called from
Item_func::aggregate_attributes_string() called from
Type_handler_string_result::Item_hybrid_func_fix_attributes() called from
Type_handler::Item_func_min_max_fix_attributes() called from
Item_func_min_max::fix_length_and_dec().
- MDEV-12504 Wrong data type for LEAST(date_expr,time_expr)
The old fix_length_and_dec() simply used the maximum of max_length
among all arguments to set its own max_length and did not take
into account that a mixture of DATE and TIME becomes DATETIME.
Now this is correctly handled by:
Type_handler_datetime_common::Item_hybrid_func_fix_attributes() called from
Type_handler::Item_func_min_max_fix_attributes() called from
Item_func_min_max::fix_length_and_dec().
3. Removes the old implementation of Item_func_min_max::fix_length_and_dec()
and replaces it to calls of the new methods.
4. Cleanup: moves the code related to unsigned_flag processing
from Type_handler_hybrid_field_type::aggregate_for_result()
to Type_handler_int_result::Item_hybrid_func_fix_attributes().
This is done:
- to avoid code duplication in
Type_handler_hybrid_field_type::aggregate_for_min_max()
- to get rid of one more call for field_type(), which is unfriendly
to the conceipt of pluggable data types.
This patch fixed some problems that occurred with subqueries that
contained directly or indirectly recursive references to recursive CTEs.
1. A [NOT] IN predicate with a constant left operand and a non-correlated
subquery as the right operand used in the specification of a recursive CTE
was considered as a constant predicate and was evaluated only once.
Now such a predicate is re-evaluated after every iteration of the process
that produces the records of the recursive CTE.
2. The Exists-To-IN transformation could be applied to [NOT] IN predicates
with recursive references. This opened a possibility of materialization
for the subqueries used as right operands. Yet, materialization
is prohibited for the subqueries if they contain a recursive reference.
Now the Exists-To-IN transformation cannot be applied for subquery
predicates with recursive references.
The function st_select_lex::check_subqueries_with_recursive_references()
is called now only for the first execution of the SELECT.
This was wrong because:
- There was no reason to rollback name for item that will be deleted
after query.
- name_length was not rolled back
- Changing real_item() doesn't work as it may be used many times in the
same query
After removing all the old code and extending the test case, all the
related test cases passes.
Sanja and I concluded that the old code isn't needed anymore. If it
still needed for some scenario not covered by our test system, it needs
to be coded in some other way, so better to remove the wrong code.
This patch implements MDEV-12514 according to the task descriptions.
It automatically fixes:
MDEV-12515 Wrong value when storing DATE_ADD() and ADDTIME() to a numeric field
Additionally:
a. Moves Item_func::set_attributes_temporal() to
Type_str_attributes::fix_attributes_temporal(),
which is a more proper place and name for it.
b. Continues replacing calls for:
set_handler_by_field_type(MYSQL_TYPE_XXX)
to corresponding:
set_handler(&type_handler_xxx)
which is faster.
Note, we should eventually get rid of almost all set_handler_by_field_type().
c. Makes type_handler_string, type_handler_time2, type_handler_newdate,
type_handler_datetime2 public.
(all built-in handlers will become public eventually)
d. Removing Item_temporal_func::sql_mode, as it was not used.
Fixed handling of default values with cached temporal functions so that the
CREATE TABLE statement now succeeds.
Fixed virtual column session cleanup.
Fixed the error message.
Added quoting of date/time values in cases when this was omitted.
Added a test case in default.test.
Updated test result files.
Fixed the bug by failing the statement with an error message that explains
that an auto-increment column may not be used in an expression for a
check constraint.
Added a test case in check_constraint.test.
Updated existing tests and results.
In case of error on opening VIEW (absent table for example) it is still possible to print its definition but some variable is not set (table_list->derived->derived) so it is better do not try to test it when there is safer alternative (table_list itself).
Working features:
CREATE OR REPLACE [TEMPORARY] SEQUENCE [IF NOT EXISTS] name
[ INCREMENT [ BY | = ] increment ]
[ MINVALUE [=] minvalue | NO MINVALUE ]
[ MAXVALUE [=] maxvalue | NO MAXVALUE ]
[ START [ WITH | = ] start ] [ CACHE [=] cache ] [ [ NO ] CYCLE ]
ENGINE=xxx COMMENT=".."
SELECT NEXT VALUE FOR sequence_name;
SELECT NEXTVAL(sequence_name);
SELECT PREVIOUS VALUE FOR sequence_name;
SELECT LASTVAL(sequence_name);
SHOW CREATE SEQUENCE sequence_name;
SHOW CREATE TABLE sequence_name;
CREATE TABLE sequence-structure ... SEQUENCE=1
ALTER TABLE sequence RENAME TO sequence2;
RENAME TABLE sequence TO sequence2;
DROP [TEMPORARY] SEQUENCE [IF EXISTS] sequence_names
Missing features
- SETVAL(value,sequence_name), to be used with replication.
- Check replication, including checking that sequence tables are marked
not transactional.
- Check that a commit happens for NEXT VALUE that changes table data (may
already work)
- ALTER SEQUENCE. ANSI SQL version of setval.
- Share identical sequence entries to not add things twice to table list.
- testing insert/delete/update/truncate/load data
- Run and fix Alibaba sequence tests (part of mysql-test/suite/sql_sequence)
- Write documentation for NEXT VALUE / PREVIOUS_VALUE
- NEXTVAL in DEFAULT
- Ensure that NEXTVAL in DEFAULT uses database from base table
- Two NEXTVAL for same row should give same answer.
- Oracle syntax sequence_table.nextval, without any FOR or FROM.
- Sequence tables are treated as 'not read constant tables' by SELECT; Would
be better if we would have a separate list for sequence tables so that
select doesn't know about them, except if refereed to with FROM.
Other things done:
- Improved output for safemalloc backtrack
- frm_type_enum changed to Table_type
- Removed lex->is_view and replaced with lex->table_type. This allows
use to more easy check if item is view, sequence or table.
- Added table flag HA_CAN_TABLES_WITHOUT_ROLLBACK, needed for handlers
that want's to support sequences
- Added handler calls:
- engine_name(), to simplify getting engine name for partition and sequences
- update_first_row(), to be able to do efficient sequence implementations.
- Made binlog_log_row() global to be able to call it from ha_sequence.cc
- Added handler variable: row_already_logged, to be able to flag that the
changed row is already logging to replication log.
- Added CF_DB_CHANGE and CF_SCHEMA_CHANGE flags to simplify
deny_updates_if_read_only_option()
- Added sp_add_cfetch() to avoid new conflicts in sql_yacc.yy
- Moved code for add_table_options() out from sql_show.cc::show_create_table()
- Added String::append_longlong() and used it in sql_show.cc to simplify code.
- Added extra option to dd_frm_type() and ha_table_exists to indicate if
the table is a sequence. Needed by DROP SQUENCE to not drop a table.
