- added join cache indication in EXPLAIN (Extra column).
- prefer filesort over full scan over
index for ORDER BY (because it's faster).
- when switching from REF to RANGE because
RANGE uses longer key turn off sort on
the head table only as the resulting
RANGE access is a candidate for join cache
and we don't want to disable it by sorting
on the first table only.
WL#3397 Refactoring storage engine test cases (for falcon)
It contains also fixes according to code review.
Contents: Testcases which were in history dedicated to InnoDB or MyISAM only.
Modifications:
1. Shift the main testing code into include/<testing field>.inc
Introduce $variables which can be used to omit tests for features which are not supported by
certain storage engines.
2. The storage engine to be tested is assigned within the toplevel script (t/<whatever>_<engine>.test)
via variable $engine_type and the the main testing code is sourced from
include/<testing field>.inc
3. Some toplevel testscripts have to be renamed to
- avoid immediate or future namespace clashes
- show via filename which storage engine is tested
4. Minor code cleanup like remove trailing spaces, some additional comments ....
