enum_mark_columns -> enum_column_usage
mark_used_columns -> column_usage
further commits will replace MARK_COLUMN_NONE with
COLUMN_READ and COLUMN_WRITE that convey the intention
without causing columns to be marked
Handle string length as size_t, consistently (almost always:))
Change function prototypes to accept size_t, where in the past
ulong or uint were used. change local/member variables to size_t
when appropriate.
This fix excludes rocksdb, spider,spider, sphinx and connect for now.
- Changing sp_rcontext::m_var_items from list of Item to list of Item_field
- Renaming sp_rcontext::get_item() to get_variable() and changing
its return type from Item* to Item_field *
- Adding sp_rcontext::get_parameter() and sp_rcontext::set_parameter(),
wrappers for get_variable() and set_variable() with extra DBUG_ASSERT.
Using new methods instead of get_variable()/set_variable() in
relevant places.
Setting non_null value drops null_value flag.
Part 1 of 3.
Part 2 will be for 10.3 including change of ps.test results.
Part 3 is test for Connector C.
This preserves const str for constant strings
Other things
- A few variables where changed from LEX_STRING to LEX_CSTRING
- Incident_log_event::Incident_log_event and record_incident where
changed to take LEX_CSTRING* as an argument instead of LEX_STRING
This was done in, among other things:
- thd->db and thd->db_length
- TABLE_LIST tablename, db, alias and schema_name
- Audit plugin database name
- lex->db
- All db and table names in Alter_table_ctx
- st_select_lex db
Other things:
- Changed a lot of functions to take const LEX_CSTRING* as argument
for db, table_name and alias. See init_one_table() as an example.
- Changed some function arguments from LEX_CSTRING to const LEX_CSTRING
- Changed some lists from LEX_STRING to LEX_CSTRING
- threads_mysql.result changed because process list_db wasn't always
correctly updated
- New append_identifier() function that takes LEX_CSTRING* as arguments
- Added new element tmp_buff to Alter_table_ctx to separate temp name
handling from temporary space
- Ensure we store the length after my_casedn_str() of table/db names
- Removed not used version of rename_table_in_stat_tables()
- Changed Natural_join_column::table_name and db_name() to never return
NULL (used for print)
- thd->get_db() now returns db as a printable string (thd->db.str or "")
After MDEV-14212, the Virtual_tmp_table instance that stores a ROW
variable elements is accessible from the underlying Field_row
(rather than Item_field_row).
This patch makes some further changes by moving the code from
sp_instr_xxx, sp_rcontext, Item_xxx to Virtual_tmp_table and Field_xxx.
The data type specific code (scalar vs ROW) now resides in
a new virtual method Field_xxx::sp_prepare_and_store_item().
The the code in sp_rcontext::set_variable() and sp_eval_expr()
is now symmetric for scalar and ROW values.
The code in sp_rcontext::set_variable_row_field(), sp_rcontext::set_variable_row_field(), sp_rcontext::set_variable_row()
is now symmetric for ROW elements (i.e. scalar and ROW elements inside a ROW).
Rationale:
Prepare the code to implement these tasks soon easier:
- MDEV-12252 ROW data type for stored function return values
- MDEV-12307 ROW data type for built-in function return values
- MDEV-6121 Data type: Array
- MDEV-10593 sql_mode=ORACLE: TYPE .. AS OBJECT: basic functionality
- ROW with ROW fields (no MDEV yet)
Details:
1. Moving the code in sp_eval_expr() responsible to backup/restore
thd->count_cuted_fields, thd->abort_on_warning,
thd->transaction.stmt.modified_non_trans_table
into a new helper class Sp_eval_expr_state, to reuse it easier.
Fixing sp_eval_expr() to use this new class.
2. Moving sp_eval_expr() and sp_prepare_func_item() from public functions
to methods in THD, so they can be reused in *.cc files easier without
a need to include "sp_head.h".
Splitting sp_prepare_func_item() into two parts.
Adding a new function sp_fix_func_item(), which fixes
the underlying items, but does not do check_cols() for them.
Reusing sp_fix_func_item() in Field_row::sp_prepare_and_store_item().
3. Moving the code to find ROW fields by name from Item to Virtual_tmp_table
Moving the code searching for ROW fields by their names
from Item_field_row::element_index_by_name() to a new method
Item_field_row to Virtual_tmp_table::sp_find_field_by_name().
Adding wrapper methods sp_rcontext::find_row_field_by_name() and
find_row_field_by_name_or_error(), to search for a ROW variable
fields by the variable offset and its field name.
Changing Item_splocal_row_field_by_name::fix_fields() to do
use sp_rcontext::find_row_field_by_name_or_error().
Removing virtual Item::element_index_by_name().
4. Splitting sp_rcontext::set_variable()
Adding a new virtual method Field::sp_prepare_and_store_item().
Spliting the two branches of the code in sp_rcontext::set_variable()
into two virtual implementations of Field::sp_prepare_and_store_item(),
(for Field and for Field_row).
Moving the former part of sp_rcontext::set_variable() with the loop
doing set_null() for all ROW fields into a new method
Virtual_tmp_table::set_all_fields_to_null() and using it in
Field_row::sp_prepare_and_store_item().
Moving the former part of sp_rcontext::set_variable() with the loop
doing set_variable_row_field() into a new method
Virtual_tmp_table::set_all_fields_from_item() and using it in
Field_row::sp_prepare_and_store_item().
The loop in the new method now uses sp_prepare_and_store_item()
instead of set_variable_row_field(), because saving/restoring
THD flags is now done on the upper level. No needs to save/restore
on every iteration.
5. Fixing sp_eval_expr() to simply do two things:
- backup/restore THD flags
- call result_field->sp_prepare_and_store_item()
So now sp_eval_expr() can be used for both scalar and ROW variables.
Reusing it in sp_rcontext::set_variable*().
6. Moving the loop in sp_rcontext::set_variable_row() into a
new method Virtual_tmp_table::sp_set_all_fields_from_item_list().
Changing the loop body to call field->sp_prepare_and_store_item()
instead of doing set_variable_row_field(). This removes
saving/restoring of the THD flags from every interation.
Instead, adding the code to save/restore the flags around
the entire loop in set_variable_row(), using Sp_eval_expr_state.
So now saving/restoring is done only once for the entire ROW
(a slight performance improvement).
7. Removing the code in sp_instr_set::exec_core() that sets
a variable to NULL if the value evaluation failed.
sp_rcontext::set_variable() now makes sure to reset
the variable properly by effectively calling sp_eval_expr(),
which calls virtual Field::sp_prepare_and_store_item().
Removing the similar code from sp_instr_set_row_field::exec_core()
and sp_instr_set_row_field_by_name::exec_core().
Removing the method sp_rcontext::set_variable_row_field_to_null(),
as it's not used any more.
8. Removing the call for sp_prepare_func_item() from
sp_rcontext::set_variable_row_field(), as it was duplicate:
it was done inside sp_eval_expr(). Now it's done inside
virtual Field::sp_prepare_and_store_item().
9. Moving the code from sp_instr_set_row_field_by_name::exec_core()
into sp_rcontext::set_variable_row_field_by_name(), for symmetry
with other sp_instr_set*::exec_core()/sp_rcontext::set_variable*() pairs.
Now sp_instr_set_row_field_by_name::exec_core() calls
sp_rcontext::set_variable_row_field_by_name().
10. Misc:
- Adding a helper private method sp_rcontext::virtual_tmp_table_for_row(),
reusing it in a new sp_rcontext methods.
- Removing Item_field_row::get_row_field(), as it's not used any more.
- Removing the "Item *result_item" from sp_eval_expr(),
as it's not needed any more.
MDEV-14957: JOIN::prepare gets unusable "conds" as argument
Do not touch merged derived (it is irreversible)
Fix first argument of in_optimizer for calls possible before fix_fields()
Many related changes.
Note that AS OF condition must always be pushed down to physical tables,
it cannot be applied to a derived or a view. Thus:
* no versioning for internal temporary tables, they can never store
historical data.
* remove special versioning code from mysql_derived_prepare and
remove ER_VERS_DERIVED_PROHIBITED - derived can have no historical
data and cannot be prohibited for system versioning related reasons.
* do not expand select list for derived/views with sys vers fields,
derived/views can never have historical data.
* remove special invisiblity rules for sys vers fields, they are no
longer needed after the previous change
* remove system_versioning_hide, it lost the meaning after the
previous change.
* remove ER_VERS_SYSTEM_TIME_CLASH, it's no "clash", the inner
AS OF clause always wins.
* non-versioned fields in a historical query
reword the warning text, downgrade to note, don't
replace values with NULLs
This reverts commit 7603463a46.
The commit itself is fine, however when disabling volatile, compiler
optimizations mess up our double results due to precision differences.
Revert the patch till a proper solution is found.
This was added in c796415943 but would hurt all other compilers
because of Visual Studio. Hopefully this has been fixed now.
Signed-off-by: Daniel Black <daniel@linux.vnet.ibm.com>
This commit implements aggregate stored functions. The basic idea behind
the feature is:
* Implement a special instruction FETCH GROUP NEXT ROW that will pause
the execution of the stored function. When the instruction is reached,
execution of the initial query resumes "as if" the function returned.
This gives the server the opportunity to advance to the next row in the
result set.
* Stored aggregates behave like regular aggregate functions. The
implementation of thus resides in the class Item_sum_sp. Because it is
an aggregate function, for each new row in the group, the
Item_sum_sp::add() method will be called. This is when execution resumes
and the function does another iteration to "add" one extra element to
the final result.
* When the end of group is reached, val_xxx() method will be called for
the item. This case is handled by another execute step for the stored
function, only with a special flag to force a call to the return
handler. See Item_sum_sp::execute() for details.
To allow this pause and resume semantic, we must preserve the function
context across executions. This is stored in Item_sp::sp_query_arena only for
aggregate stored functions, but has no impact for regular functions.
We also enforce aggregate functions to include the "FETCH GROUP NEXT ROW"
instruction.
Signed-off-by: Vicențiu Ciorbaru <vicentiu@mariadb.org>
In preparation for implementing custom aggregate functions, refactor
the common code between regular stored functions and aggregate stored
functions. This includes:
* initialising SP result field
* executing a SP
* access checks
In addition, refactor sp_head::execute_function to take two extra
parameters, a function rcontext and a Query_arena. These two paremeters
were initially initialised and destroyed within
sp_head::execute_function, but for aggregate stored functions we will
require control over their lifetime. The owner of these objects now
becomes Item_sp.
Signed-off-by: Vicențiu Ciorbaru <vicentiu@mariadb.org>
1. Removing data type specific constants from enum_item_param_state,
adding SHORT_DATA_VALUE instead.
2. Replacing tests for Item_param::state for the removed constants to
tests for Type_handler::cmp_type() against {INT|REAL|TIME|DECIAML}_RESULT.
Deriving Item_param::PValue from Type_handler_hybrid_field_type,
to store the data type handler of the current value of the parameter.
3. Moving Item_param::decimal_value and Item_param::str_value_ptr
to Item_param::PValue. Adding Item_param::PValue::m_string
and changing Item_param to use it to store string values,
instead of Item::str_value. The intent is to replace Item_param::value
to a st_value based implementation in the future, to avoid duplicate code.
Adding a sub-class Item::PValue_simple, to implement
Item_param::PValue::swap() easier.
Remaming Item_basic_value::fix_charset_and_length_from_str_value()
to fix_charset_and_length() and adding the "CHARSET_INFO" pointer
parameter, instead of getting it directly from item->str_value.charset().
Changing Item_param to pass value.m_string.charset() instead
of str_value.charset().
Adding a String argument to the overloaded
fix_charset_and_length_from_str_value() and changing Item_param
to pass value.m_string instead of str_value.
4. Replacing the case in Item_param::save_in_field() to a call
for Type_handler::Item_save_in_field().
5. Adding new methods into Item_param::PValue:
val_real(), val_int(), val_decimal(), val_str().
Changing the corresponding Item_param methods
to use these new Item_param::PValue methods
internally. Adding a helper method
Item_param::can_return_value() and removing
duplicate code in Item_param::val_xxx().
6. Removing value.set_handler() from Item_param::set_conversion()
and Type_handler_xxx::Item_param_set_from_value().
It's now done inside Item_param::set_param_func(),
Item_param::set_value() and Item_param::set_limit_clause_param().
7. Changing Type_handler_int_result::Item_param_set_from_value()
to set max_length using attr->max_length instead of
MY_INT64_NUM_DECIMAL_DIGITS, to preserve the data type
of the assigned expression more precisely.
8. Adding Type_handler_hybrid_field_type::swap(),
using it in Item_param::PValue::swap().
9. Moving the data-type specific code from
Item_param::query_val_str(), Item_param::eq(),
Item_param::clone_item() to
Item_param::value_query_type_str(),
Item_param::value_eq(), Item_param::value_clone_item(),
to split the "state" dependent code and
the data type dependent code.
Later we'll split the data type related code further
and add new methods in Type_handler. This will be done
after we replace Item_param::PValue to st_value.
10. Adding asserts into set_int(), set_double(), set_decimal(),
set_time(), set_str(), set_longdata() to make sure that
the value set to Item_param corresponds to the previously
set data type handler.
11. Adding tests into t/ps.test and suite/binlog/t/binlog_stm_ps.test,
to cover Item_param::print() and Item_param::append_for_log()
for LIMIT clause parameters.
Note, the patch does not change the behavior covered by the new
tests. Adding for better code coverage.
12. Adding tests for more precise integer data type in queries like this:
EXECUTE IMMEDIATE
'CREATE OR REPLACE TABLE t1 AS SELECT 999999999 AS a,? AS b'
USING 999999999;
The explicit integer literal and the same integer literal
passed as a PS parameter now produce columns of the same data type.
Re-recording old results in ps.result, gis.result, func_hybrid_type.result
accordingly.
- sql_prepare.cc: Moving functions set_param_xxx() as
methods to Item_param
- Replacing a pointer to a function Item_param::set_param_func
to Type_handler based implementation:
Item_param::value now derives from Type_handler_hybrid_field_type.
Adding new virtual methods Type_handler::Item_param_setup_conversion()
and Type_handler::Item_param_set_param_func()
- Moving declaration of some Item_param members from "public:" to "private:"
(CONVERSION_INFO, value, decimal_value)
- Adding a new method Item_param::set_limit_clause_param(),
to share duplicate code, as well as to encapsulate
Item_param::value.
- Adding Item_param::setup_conversion_string() and
Item_param::setup_conversion_blob() to share
the code for binding from a client value
(mysql_stmt_bind_param), and for binding from
an expression (Item).
- Removing two different functions set_param_str_or_null()
and set_param_str(). Adding a common method Item_param::set_param_str().
Item_param::m_empty_string_is_null, used by Item_param::set_param_str().
- Removing the call for setup_one_conversion_function() from
insert_params_from_actual_params_with_log(). It's not needed,
because the call for ps_param->save_in_param() makes sure
to initialized all data type dependent members properly,
by calling setup_conversion_string() from
Type_handler_string_result::Item_param_set_from_value()
and by calling setup_conversion_blob() from
Type_handler_blob_common::Item_param_set_from_value()
- Cleanup: removing multiplication to MY_CHARSET_BIN_MB_MAXLEN
in a few places. It's 1 anyway, and will never change.
TODO:
- Make get_thd_memroot() inline
- To do this, we need to reduce dependence of include files, especially
so that sql_class.h is not depending in item.h
