Fixing the asymmetry in the array field_types_merge_rules[][]
which caused data loss when mixing FLOAT + BIGINT in UNIONs
or hybrid functions:
1. FLOAT + INT = DOUBLE
2. FLOAT + BIGINT = FLOAT
3. INT + FLOAT = DOUBLE
4. BIGINT + FLOAT = DOUBLE
Now FLOAT + BIGINT (as in #2) also produces DOUBLE, like the cases #1,#3,#4 do.
make insert NULL into a timestamp mark the field as having an
explicit value. So that the field won't be assigned the value
again in TABLE::update_default_field()
make Item_func_now_local::save_in_field(timestamp_field) not to go
through MYSQL_TIME - this conversion is lossy around DST change times.
This fixes inserting a default value into a timestamp field.
Implement a special Copy_field method for timestamps, that copies
timestamps without converting them to MYSQL_TIME (the conversion
is lossy around DST change dates).
When creating an Item_direct_view_ref we were setting the
Name_resolution_context based on TABLE_LIST::view member variable.
However, for derived tables this member is NULL. To not set a wrong
context, if TABLE_LIST::view is empty, use THD::lex instead.
Window functions can not be used as arguments to aggregate functions, as
the aggregation happens before window function computation. Disallow
such constructs by returning an error.
In order to detect this case a change was needed in the base
Item_sum_xxx::fix_fields to propagate the with_window_func flag.
Item_func_group_concat requires the same change.
Item_cond did not correctly propagate with_window_func flag in the Item
tree. Without it, we would not call Item::split_sum_func correctly and the
window function's result_field would remain NULL.
This is backport of 25ad623d64 for 10.2.
The issue is similar to the one from MDEV-13240. Item::save_in_field()
returns an error during tmp table population in a create table from select query
as we try to save an empty string as a date value when
force_return_blank is set to true for window functions.
MDEV-13240 Wrong warning with MAX(datetime_field) OVER (...)
The problem resided in Item_window_func implementation,
and it was revealed by bb-10.2-ext specific changes:
Item_window_func::save_in_field() works differently in bb-10.2-ext vs 10.2:
- 10.2 goes through val_str()
- bb-10.2-ext goes through get_date(), due to Type_handler related changes.
get_date() tries to convert empty string to DATETIME, hence the warning.
During a discussion with Vicentiu, it was decided to fix
Item_window_func::val_xxx() to return NULL
(instead of an "empty" value, such as 0 for numbers and '' for strings)
when force_return_blank is set.
When printing an expression, like a/(b*c), we need to print parentheses,
even though / and * have the same precedence. Basically, we should
always treat the second argument as having one level higher precedence
than it normally is.
SQL Standard (4.23.3.4 Table check constraints, part 2, SQL:2016) says
that CHECK constraint rejects rows *only* if the condition is FALSE.
That is, both TRUE and NULL should be allowed.
This should also fix the MariaDB 10.2.2 bug
MDEV-13826 CREATE FULLTEXT INDEX on encrypted table fails.
MDEV-12634 FIXME: Modify innodb-index-online, innodb-table-online
so that they will write and read merge sort files. InnoDB 5.7
introduced some optimizations to avoid using the files for small tables.
Many collation test results have been adjusted for MDEV-10191.
The problem was introduced by the patch for MDEV-7661,
which (in addition to the fix itself) included an attempt to make
CONVERT/CAST work in the same way with fields
(i.e. return NULL in strict mode if a non-convertable character found).
It appeared to be a bad idea and some users were affected by this
behavior change. Changing CONVERT/CAST not depend on sql_mode
(restoring pre-10.1.4 behavior).
Now we allow derived in the from clause of subqueries so set
flag which prevent optimisation of subqueries during view
creation before derived processing so subquery will be
correctly printed in the view .frm.
