- wait for schema event also if mysqld is a single one in cluster to ensure serialization with data events
+ some current_thd removals
+ enabling kill of sql thread during shema sync wait
(The above problem only occurs with -T -- create a separate file for
each table / view.) This ChangeSet results in correct output of view-
information while omitting the information for the view's stand-in
table. The rationale is that with -T, the user is likely interested
in transferring part of a database, not the db in its entirety (that
would be difficult as replay order is obscure, the files being named
for the table/view they contain rather than getting a sequence number).
'show create' works even on views that are short of a base-table (this
throw a warning though, like you would expect). Unfortunately, this is
not what mysqldump uses; it creates stand-in tables and hence requests
'show fields' on the view which fails with missing base-tables. The
--force option prevents the dump from stopping at this point; furthermore
this patch dumps a comment showing create for the offending view for
better diagnostics. This solution was confirmed by submitter as solving
their/clients' problem. Problem might become non-issue once mysqldump no
longer creates stand-in tables.
Bug#18282 "INFORMATION_SCHEMA.TABLES provides inconsistent info about invalid views"
This bug caused crashes or resulted in wrong data being returned
when one tried to obtain information from I_S tables about views
using stored functions.
It was caused by the fact that we were using LEX representing
statement which were doing select from I_S tables as active LEX
when contents of I_S table were built. So state of this LEX both
affected and was affected by open_tables() calls which happened
during this process. This resulted in wrong behavior and in
violations of some of invariants which caused crashes.
This fix tries to solve this problem by properly saving/resetting
and restoring part of LEX which affects and is affected by the
process of opening tables and views in get_all_tables() routine.
To simplify things we separated this part of LEX in a new class
and made LEX its descendant.
The IN() function uses agg_cmp_type() to aggregate all types of its arguments
to find out some common type for comparisons. In this particular case the
char() and the int was aggregated to double because char() can contain values
like '1.5'. But all strings which do not start from a digit are converted to
0. thus 'a' and 'z' become equal.
This behaviour is reasonable when all function arguments are constants. But
when there is a field or an expression this can lead to false comparisons. In
this case it makes more sense to coerce constants to the type of the field
argument.
The agg_cmp_type() function now aggregates types of constant and non-constant
items separately. If some non-constant items will be found then their
aggregated type will be returned. Thus after the aggregation constants will be
coerced to the aggregated type.
