into  adventure.(none):/home/thek/Development/cpp/bug27415/my51-bug27415

 - Problem was reported as a SP variable using itself as 
   right value inside SUBSTR caused corruption of data. 
 - This bug could not be verified in either 5.0bk or 5.1bk
 - Added test case to prevent future regressions.

into  vajra.(none):/opt/local/work/mysql-5.1-runtime

into  vajra.(none):/opt/local/work/mysql-5.1-runtime

into  vajra.(none):/opt/local/work/mysql-5.0-runtime

into  vajra.(none):/opt/local/work/mysql-5.0-runtime

into  vajra.(none):/opt/local/work/mysql-4.1-runtime

into  mockturtle.local:/home/dlenev/src/mysql-5.1-cts-3

TABLES" and failures of alter_table.test on Windows which occured after
pushing fix for bugs #20662, #20903, #24508, #24738 (various problems
with CREATE TABLE SELECT).

ALTER TABLE statements which were handled using "fast" alter table
optimization were not properly working under LOCK TABLES if table
was transactional (for all table types under Windows).

Code implementing "fast" version of ALTER TABLE tried to open and
lock table using open_ltable() after renaming .FRM files (which
corresponds to renaming tables in normal case) in some cases
(for transactional tables or on Windows). This caused problems
under LOCK TABLES and conflicted with name-lock taken by 
ALTER TABLE RENAME on target tables.

This patch solves this issue by using reopen_name_locked_table()
instead of open_ltable().

into  vajra.(none):/opt/local/work/mysql-5.1-runtime

into  bk-internal.mysql.com:/data0/bk/mysql-5.1-opt

into  bk-internal.mysql.com:/data0/bk/mysql-5.0-opt

into  olga.mysql.com:/home/igor/mysql-5.1-opt

into  olga.mysql.com:/home/igor/mysql-5.1-opt

a crash when the left operand of the predicate is evaluated to NULL.
It happens when the rows from the inner tables (tables from the subquery)
are accessed by index methods with key values obtained by evaluation of
the left operand of the subquery predicate. When this predicate is
evaluated to NULL an alternative access with full table scan is used
to check whether the result set returned by the subquery is empty or not.
The crash was due to the fact the info about the access methods used for
regular key values was not properly restored after a switch back from the
full scan access method had occurred.
The patch restores this info properly.
The same problem existed for queries with IN subquery predicates if they
were used not at the top level of the queries.

into  moonbone.local:/mnt/gentoo64/work/27878-bug-5.0-opt-mysql

  Corrected test case for the bug#27878.

into  mockturtle.local:/home/dlenev/src/mysql-5.1-cts-3

into  mysql.com:/home/hf/work/27957/my51-27957

into  mysql.com:/home/hf/work/27957/my50-27957

into  moonbone.local:/mnt/gentoo64/work/27878-bug-5.0-opt-mysql

database.

If a user has a right to update anything in the current database then the 
access was granted and further checks of access rights for underlying tables
wasn't done correctly. The check is done before a view is opened and thus no
check of access rights for underlying tables can be carried out.
This allows a user to update through a view a table from another database for
which he hasn't enough rights.

Now the mysql_update() and the mysql_test_update() functions are forces
re-checking of access rights after a view is opened.

into  mockturtle.local:/home/dlenev/src/mysql-5.1-cts-3

into  mockturtle.local:/home/dlenev/src/mysql-5.0-cts-3

into  mockturtle.local:/home/dlenev/src/mysql-5.1-cts-3

  Bug #20662 "Infinite loop in CREATE TABLE IF NOT EXISTS ... SELECT
              with locked tables"
  Bug #20903 "Crash when using CREATE TABLE .. SELECT and triggers"
  Bug #24738 "CREATE TABLE ... SELECT is not isolated properly"
  Bug #24508 "Inconsistent results of CREATE TABLE ... SELECT when
              temporary table exists"

Deadlock occured when one tried to execute CREATE TABLE IF NOT
EXISTS ... SELECT statement under LOCK TABLES which held
read lock on target table.
Attempt to execute the same statement for already existing
target table with triggers caused server crashes.
Also concurrent execution of CREATE TABLE ... SELECT statement
and other statements involving target table suffered from
various races (some of which might've led to deadlocks).
Finally, attempt to execute CREATE TABLE ... SELECT in case
when a temporary table with same name was already present
led to the insertion of data into this temporary table and
creation of empty non-temporary table.
 
All above problems stemmed from the old implementation of CREATE
TABLE ... SELECT in which we created, opened and locked target
table without any special protection in a separate step and not
with the rest of tables used by this statement.
This underminded deadlock-avoidance approach used in server
and created window for races. It also excluded target table
from prelocking causing problems with trigger execution.

The patch solves these problems by implementing new approach to
handling of CREATE TABLE ... SELECT for base tables.
We try to open and lock table to be created at the same time as
the rest of tables used by this statement. If such table does not
exist at this moment we create and place in the table cache special
placeholder for it which prevents its creation or any other usage
by other threads.
We still use old approach for creation of temporary tables.

Note that we have separate fix for 5.0 since there we use slightly
different less intrusive approach.

  Bug #20662 "Infinite loop in CREATE TABLE IF NOT EXISTS ... SELECT
              with locked tables"
  Bug #20903 "Crash when using CREATE TABLE .. SELECT and triggers"
  Bug #24738 "CREATE TABLE ... SELECT is not isolated properly"
  Bug #24508 "Inconsistent results of CREATE TABLE ... SELECT when
              temporary table exists"
 
Deadlock occured when one tried to execute CREATE TABLE IF NOT
EXISTS ... SELECT statement under LOCK TABLES which held
read lock on target table.
Attempt to execute the same statement for already existing
target table with triggers caused server crashes.
Also concurrent execution of CREATE TABLE ... SELECT statement
and other statements involving target table suffered from
various races (some of which might've led to deadlocks).
Finally, attempt to execute CREATE TABLE ... SELECT in case
when a temporary table with same name was already present
led to the insertion of data into this temporary table and
creation of empty non-temporary table.
 
All above problems stemmed from the old implementation of CREATE
TABLE ... SELECT in which we created, opened and locked target
table without any special protection in a separate step and not
with the rest of tables used by this statement.
This underminded deadlock-avoidance approach used in server
and created window for races. It also excluded target table
from prelocking causing problems with trigger execution.
  
The patch solves these problems by implementing new approach to
handling of CREATE TABLE ... SELECT for base tables.
We try to open and lock table to be created at the same time as
the rest of tables used by this statement. If such table does not
exist at this moment we create and place in the table cache special
placeholder for it which prevents its creation or any other usage
by other threads.

We still use old approach for creation of temporary tables.

Also note that we decided to postpone introduction of some tests
for concurrent behaviour of CREATE TABLE ... SELECT till 5.1.
The main reason for this is absence in 5.0 ability to set @@debug
variable at runtime, which can be circumvented only by using several
test files with individual .opt files. Since the latter is likely
to slowdown test-suite unnecessary we chose not to push this tests
into 5.0, but run them manually for this version and later push
their optimized version into 5.1

into  mysql.com:/home/hf/work/27957/my51-27957