row_search_mvcc(): Relax debug assertions. For NO_ROLLBACK tables,
a transaction or a read view will not be started at the start of
a statement.

row_upd_clust_step(): Support CREATE TEMPORARY SEQUENCE or
CREATE TEMPORARY TABLE…NO_ROLLBACK.

A cleanup for MDEV-11514, MDEV-11497, MDEV-11554, MDEV-11555 - IN and CASE type aggregation problems

Removing cmp_item::get_comparator() and calling instead
Type_handler::make_cmp_item(), which was earlier introduced by this patch:

74891ed2

This is a joint patch fixing the following problems:

MDEV-12875 Wrong VIEW column data type for COALESCE(int_column)
MDEV-12886 Different default for INT and BIGINT column in a VIEW for a SELECT with ROLLUP
MDEV-12916 Wrong column data type for an INT field of a cursor-anchored ROW variable

All above problem happened because the global function ::create_tmp_field()
called the top-level Item::create_tmp_field(), which made some tranformation
for INT-result data types. For example, INT(11) became BIGINT(11), because 11
is a corner case and it's not known if it fits or does not fit into INT range,
so Item::create_tmp_field() converted it to BIGINT(11) for safety.

The main idea of this patch is to avoid such tranformations.

1. Fixing Item::create_tmp_field() not to have a special case for INT_RESULT.

   Item::create_tmp_field() is changed not to have a special case
   for INT_RESULT (which earlier made a decision based on Item's max_length).
   It now calls tmp_table_field_from_field_type() for INT_RESULT,
   therefore preserves the original data type (e.g. INT, YEAR) without
   conversion to BIGINT.

   This change is valid, because a number of recent fixes
   (e.g. in Item_func_int, Item_hybrid_func, Item_int, Item_splocal)
   guarantee that item->type_handler() now properly returns
   type_handler_long vs type_handler_longlong. So no adjustment by length
   is needed any more for Items returning INT_RESULT.

   After this change, Item::create_tmp_field() calls
   tmp_table_field_from_field_type() for all XXX_RESULT, except REAL_RESULT.

2. Fixing Item::create_tmp_field() not to have a special case for REAL_RESULT.

   Note, the reason for a special case for REAL_RESULT is to have a special
   constructor for Field_double(), forcing Field_real::not_fixed to be set
   to true.

   Taking into account that only Item_sum descendants actually need a special
   constructor call Field_double(not_fixed=true), not too loose precision
   when mixing individual rows to the aggregate result:
   - renaming Item::create_tmp_field() to Item_sum::create_tmp_field().
   - changing Item::create_tmp_field() just to call
     tmp_table_field_from_field_type() for all XXX_RESULT types.

   A special case for REAL_RESULT in Item::create_tmp_field() is now gone.
   Item::create_tmp_field() is now symmetric for all XXX_RESULT types,
   and now just calls tmp_table_field_from_field_type().

3. Fixing Item_func::create_field_for_create_select() not to have
   a special case for STRING_RESULT.

   After changes #1 and #2, the code in
   Item_func::create_field_for_create_select(), testing result_type(),
   becomes useless, because: now Item::create_tmp_field() and
   tmp_table_field_from_field_type() do exactly the same thing for all
   XXX_RESULT types for Item_func descendants:
   a. It calls tmp_table_field_from_field_type for STRING_RESULT directly.
   b. For other XXX_RESULT, it goes through Item::create_tmp_field(),
      which calls the global function ::create_tmp_field(),
      which calls item->create_tmp_field() for FUNC_ITEM,
      which calls tmp_table_field_from_field_type() again.

   So removing the virtual implementation of
   Item_func::create_field_for_create_select().
   The inherited Item::create_field_for_create_select() now perfectly
   does the job, as it also calls tmp_table_field_from_field_type()
   for FUNC_ITEM, independently from XXX_RESULT type.

4. Taking into account #1 and #2, as well as some recent changes,
   removing virtual implementations:
   - Item_hybrid_func::create_tmp_field()
   - Item_hybrid_func::create_field_for_create_select()
   - Item_int_func::create_tmp_field()
   - Item_int_func::create_field_for_create_select()
   - Item_temporal_func::create_field_for_create_select()
   The derived versions from Item now perfectly work.

5. Moving a piece of code from create_tmp_field_from_item()
   to a new function create_tmp_field_from_item_finalize(),
   to reuse it in two places (see #6).

6. Changing the code responsible for BIT->INT/BIGIN tranformation
   (which is called for the cases when the created table, e.g. HEAP,
    does not fully support BIT) not to call create_tmp_field_from_item(),
   because the latter now calls tmp_table_field_from_field_type() instead
   of create_tmp_field() and thefore cannot do BIT transformation.
   So rewriting this code using a sequence of these calls:
   - item->type_handler_long_or_longlong()
   - handler->make_and_init_table_field()
   - create_tmp_field_from_item_finalize()

7. Miscelaneous changes:
   - Moving type_handler_long_or_longlong() from "protected" to "public",
     as it's now needed in the global function create_tmp_field().

8. The above changes fixed MDEV-12875, MDEV-12886, MDEV-12916.
   So adding tests for these bugs.

The fix for MDEV-12876 fixed this problem as well.
So adding tests only.

- Test with LOCK TABLES
- Test mysqldump
- Don't update rows for sequence tables if values doesn't change. This is
  needed as InnoDB gives an error for updates where values doesn't change.

Because SEQUENCE objects or NO_ROLLBACK tables do not support locking
or MVCC or transactions, avoid starting a transaction.

row_upd_step(): Do not start a transaction. Let the caller do that.

que_thr_step(): Call trx_start_if_not_started_xa() for QUE_NODE_UPDATE.
(The InnoDB SQL parser is not used for accessing NO_ROLLBACK tables.)

row_ins_step(): Correct a too strict assertion and comment about
concurrency. Multiple concurrent readers are allowed.

row_update_for_mysql_using_upd_graph(): Do not start the transaction
for NO_ROLLBACK tables.

row_search_mvcc(): For NO_ROLLBACK tables, skip locking even inside
LOCK TABLES. Only call trx_start_if_not_started() at the start
of a statement, not for each individual request.

The patch broke expressions like CAST(1.0e+300 AS SIGNED INT)
in binary protocol, e.g.:
  mtr --ps cast

Short real numbers like 1.0e+300 can return huge values,
so using args[0]->max_length is not reliable to choose properly the result
type for Item_func_signed and Item_func_unsigned (between INT and BIGINT).

Setting Item_[un]signed_typecast::max_length to MAX_BIGINT_WIDTH
when doing CAST from FLOAT/DOUBLE, to force type_handler() return
&type_handler_longlong rather than &type_handler_long.

- Old sequence code forced row based replication for any statements that
  refered to a sequence table. What is new is that row based replication
  is now sequence aware:
   - NEXT VALUE is now generating a short row based event with only
     next_value and round being replicated.
   - Short row based events are now on the slave updated as trough
     SET_VALUE(sequence_name)
   - Full row based events are on the slave updated with a full insert,
     which is practically same as ALTER SEQUENCE.
- INSERT on a SEQUENCE table does now a EXCLUSIVE LOCK to ensure that
  it is logged in binary log before any following NEXT VALUE calls.
- Enable all sequence tests and fixed found bugs
- ALTER SEQUENCE doesn't anymore allow changes that makes the next_value
  outside of allowed range
- SEQUENCE changes are done with TL_WRITE_ALLOW_WRITE. Because of this
  one can generate a statement for MyISAM with both
  TL_WRITE_CONCURRENT_INSERT and TL_WRITE_ALLOW_WRITE. To fix a warning
  I had to add an extra test in thr_lock.c for this.
- Removed UPDATE of SEQUENCE (no need to support this as we
  have ALTER SEQUENCE, which takes the EXCLUSIVE lock properly.
- Removed DBUG_ASSERT() in MDL_context::upgrade_shared_lock. This was
  removed upstream in MySQL 5.6 in 72f823de453.
- Simplified test in decided_logging_format() by using sql_command_flags()
- Fix that we log DROP SEQUENCE correctly.
- Fixed that Aria works with SEQUENCE

Fixing a few problems with data type and metadata for INT result functions (MDEV-12852, MDEV-12853, MDEV-12869)

This is a joint patch for:
MDEV-12852 Out-of-range errors when CAST(1-2 AS UNSIGNED
MDEV-12853 Out-of-range errors when CAST('-1' AS UNSIGNED
MDEV-12869 Wrong metadata for integer additive and multiplicative operators

1. Fixing all Item_func_numhybrid descendants to set the precise
   data type handler (type_handler_long or type_handler_longlong)
   at fix_fields() time. This fixes MDEV-12869.

2. Fixing Item_func_unsigned_typecast to set the precise data type handler
   at fix_fields() time. This fixes MDEV-12852 and MDEV-12853.
   This is done by:
   - fixing Type_handler::Item_func_unsigned_fix_length_and_dec()
     and Type_handler_string_result::Item_func_unsigned_fix_length_and_dec()
     to properly detect situations when a negative epxression is converted
     to UNSIGNED. In this case, length of the result is now always set to
     MAX_BIGINT_WIDTH without trying to use args[0]->max_length, as very
     short arguments can produce very long result in such conversion:
        CAST(-1 AS UNSIGNED) -> 18446744073709551614
   - adding a new virtual method "longlong Item::val_int_max() const",
     to preserve the old behavior for expressions like this:
        CAST(1 AS UNSIGNED)
     to stay under the INT data type (instead of BIGINT) for small
     positive integer literals. Using Item::unsigned_flag would not help,
     because Item_int does not set unsigned_flag to "true" for positive
     numbers.

3. Adding helper methods:
  * Item::type_handler_long_or_longlong()
  * Type_handler::type_handler_long_or_longlong()
  and reusing them in a few places, to reduce code duplication.

4. Making reorganation in create_tmp_field() and
   create_field_for_create_select() for Item_hybrid_func and descendants,
   to reduce duplicate code. They all now have a similar behavior in
   respect of creating fields. Only Item_func_user_var descendants have
   a different behavior. So moving the default behvior to Item_hybrid_func,
   and overriding behavior on Item_func_user_var level.

MDEV-12858 + MDEV+12859 + MDEV-12862 - a join patch fixing a few data type problems with CREATE..SELECT

MDEV-12858 Out-of-range error for CREATE..SELECT unsigned_int_column+1
MDEV-12859 Out-of-range error for CREATE..SELECT @A:=EXTRACT(MINUTE_MICROSECOND FROM..)
MDEV-12862 Data type of @A:=1e0 depends on the session character set

1. Moving a part of Item::create_tmp_field() into a new helper method
   Item::create_tmp_field_int() and reusing it in Item::create_tmp_field()
   and Item_func_signed::create_tmp_field().
   Fixing the code in Item::create_tmp_field_int() to call
   Type_handler::make_table_field() instead of doing "new Field_long[long]"
   directly. This change revealed a problem reported in MDEV-12862.

2. Changing the "long vs longlong" cut-off length for
     - Item_func::create_tmp_field()
     - Item_sum::create_tmp_field()
     - Item_func_get_user_var::create_tmp_field()
   from MY_INT32_NUM_DECIMAL_DIGITS to (MY_INT32_NUM_DECIMAL_DIGITS - 2).
   This fixes MDEV-12858.
   After this change, the "convert_int_length" parameter to
   Item::create_tmp_field() is not needed any more, because
   (MY_INT32_NUM_DECIMAL_DIGITS - 2) is always passed.
   So removing the "convert_int_length" parameter.

3. Fixing Item::create_tmp_field() to pass max_char_length() instead
   of max_length to the constructor of Field_double().
   This fixes MDEV-12862.

4. Additionally, fixing
   - Type_handler_{tiny|short|int24|long|longlong}::make_table_field()
   - Type_handler_{float|double}::make_table_field()
   to pass max_char_length() instead of max_length to Field contructors.
   This is needed by the change (1).

5. Adding new tests, and recording new correct results in the old tests in:
   - mysql-test/r/type_ranges.result
   - storage/tokudb/mysql-test/tokudb/r/type_ranges.result

MDEV-12860 Out-of-range error on CREATE..SELECT with a view using MAX and EXTRACT(MINUTE_MICROSECOND..)

This is a joint patch for:

MDEV-12856 Wrong result set metadata for DIV
MDEV-12857 Out-of-range errors on CREATE..SELECT 2222222222 DIV 1

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.

MDEV-12833 Split Column_definition::create_length_to_internal_length() to virtual methods in Type_handler

MDEV-12826 Add Type_handler::val_int_signed_typecast() and Type_handler::val_int_unsigned_typecast()

- Adding new virtual methods in Type_handler:
  * Column_definition_prepare_stage1()
  * Column_definition_prepare_stage2()
  * calc_pack_length()

- Using new methods to remove type specific code in:
  * Global function calc_pack_length()
  * Column_definition::prepare_create_field()
  * The loop body mysql_prepare_create_table()
  * Column_definition::sp_prepare_create_field()

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)

MDEV-12798 Item_param does not preserve exact field type in EXECUTE IMMEDIATE 'CREATE TABLE AS SELECT ?' USING POINT(1,1)

This push just fixes tests, nothing wrong in server

"mtr --ps func_str" failed:
pad_str was erroneously appended with a new space on every PS execution.

Adding pad_str.length(0) into fix_length_and_dec() to avoid this.

This patch for MDEV-12770 is also fixing:

MDEV-12769 Arithmetic operators with temporal types create excessive column types

- SETVAL(sequence_name, next_value, is_used, round)
- ALTER SEQUENCE, including RESTART WITH

Other things:
- Added handler::extra() option HA_EXTRA_PREPARE_FOR_ALTER_TABLE to signal
  ha_sequence() that it should allow write_row statments.
- ALTER ONLINE TABLE now works with SEQUENCE:s

Other things
- Ensure that ut_d() is set to EXPR if ut_ad() is DEBUG_ASSERT()
  If not, we will get a crash in purge_sys_t::~purge_sys_t() as
  this ut_ad() code expect's that the ut_d() codes has been executed