The name resolution for correlated subqueries and HAVING clauses
failed to distinguish which of two was being performed when there
was a reference to an outer aliased field.
Fixed by adding the condition that HAVING clause name resulotion
is being performed.
value when inserting into a view.
The mysql_prepare_insert function checks all fields of the target table that
directly or indirectly (through a view) are specified in the INSERT
statement to have a default value. This check can be skipped if the INSERT
statement doesn't mention any insert fields. In case of a view this allows
fields that aren't mentioned in the view to bypass the check.
Now fields of the target table are always checked to have a default value
when insert goes into a view.
columns (default datatype value is assigned).
The mysql_update function has been modified to generate
an error when trying to set a NOT NULL field to NULL rather than a warning
in the set_field_to_null_with_conversions function.
When resolving references we need to take into consideration
the view "fields" and allow qualified access to them.
Fixed by extending the reference resolution to process view
fields correctly.
server crash.
The filesort implementation has an optimization for subquery execution which
consists of reusing previously allocated buffers. In particular the call to
the read_buffpek_from_file function might be skipped when a big enough buffer
for buffer descriptors (buffpeks) is already allocated. Beside allocating
memory for buffpeks this function fills allocated buffer with data read from
disk. Skipping it might led to using an arbitrary memory as fields' data and
finally to a crash.
Now the read_buffpek_from_file function is always called. It allocates
new buffer only when necessary, but always fill it with correct data.
Reseting the query cache by issuing a SET GLOBAL query_cache_size=0 caused the server
to crash if a the server concurrently was saving a new result set to the query cache. The
reason for this was that the invalidation wasn't waiting on the result writers to
release the block level locks on the query cache.
to be compiled in
The problem was that on a statically built server an attempt to create
a UDF resulted in a different, but reasonable error ("Can't open shared
library" instead of "UDFs are unavailable with the --skip-grant-tables
option"), which caused a failure for the test case for bug #32020.
Fixed by moving the test case for bug #32020 from skip_grants.test to a
separate test to ensure that it is only run when the server is built
with support for dynamically loaded libraries.
w/ Field_date instead of Field_newdate
Field_date was still used in temp table creation.
Fixed by using Field_newdate consistently throughout the server
except when reading tables defined with older MySQL version.
No test suite is possible because both Field_date and Field_newdate
return the same values in all the metadata calls.
Parser rejects ODBC's escape sequences for outer joins other
than left outer join, yet the escape sequence BNF specifies
that this syntax can be used for left, right, and full outer
join syntax.
The problem is that although the MySQL Connector/ODBC advertises
"Outer Join Escape Sequence" capabilities, the parsing is done
in the server and historically it only supported this syntax
for left outer joins and applications such as Crystal Reports
11 tries to use this syntax for inner joins.
The chosen solution is to reorganize a couple of parser rules
to ignore any kind of SQL escape sequence. Ignoring the escape
sequences is harmless because the various SQL join clauses
are supported by the server.
that the entire server uses their public ha_* counterparts instead,
since only then we can ensure proper tracing of these calls that
is necessary for Bug#12713.
A pre-requisite for Bug#12713 "Error in a stored function called from
a SELECT doesn't cause ROLLBACK of statem"
The checks in the test for bug #12480 were too wide and
made the test to depend on the procedures and triggers
present in the server.
Corrected the test to check only for the procedure and
trigger it creates.
In a union without braces, the order by at the end is applied to the
overall union. It therefore should not interfere with the individual
select parts of the union.
Fixed by changing our parser rules appropriately.
with null values
For queries containing GROUP_CONCAT(DISTINCT fields ORDER BY fields), there
was a limitation that the DISTINCT fields had to be the same as ORDER BY
fields, owing to the fact that one single sorted tree was used for keeping
track of tuples, ordering and uniqueness. Fixed by introducing a second
structure to handle uniqueness so that the original structure has only to
order the result.
subselects into account
It is forbidden to use the SELECT INTO construction inside UNION statements
unless on the last SELECT of the union. The parser records whether it
has seen INTO or not when parsing a UNION statement. But if the INTO was
legally used in an outer query, an error is thrown if UNION is seen in a
subquery. Fixed in 5.0 by remembering the nesting level of INTO tokens and
mitigate the error unless it collides with the UNION.
The problem is that some DDL statements (ALTER TABLE, CREATE
TRIGGER, FLUSH TABLES, ...) when under LOCK TABLES need to
momentarily drop the lock, reopen the table and grab the write
lock again (using reopen_tables). When grabbing the lock again,
reopen_tables doesn't pass a flag to mysql_lock_tables in
order to ignore the impending global read lock, which causes a
assertion because LOCK_open is being hold. Also dropping the
lock must not signal to any threads that the table has been
relinquished (related to the locking/flushing protocol).
The solution is to correct the way the table is reopenned
and the locks grabbed. When reopening the table and under
LOCK TABLES, the table version should be set to 0 so other
threads have to wait for the table. When grabbing the lock,
any other flush should be ignored because it's theoretically
a atomic operation. The chosen solution also fixes a potential
discrepancy between binlog and GRL (global read lock) because
table placeholders were being ignored, now a FLUSH TABLES WITH
READ LOCK will properly for table with open placeholders.
It's also important to mention that this patch doesn't fix
a potential deadlock if one uses two GRLs under LOCK TABLES
concurrently.
cause ROLLBACK of statement", part 1. Review fixes.
Do not send OK/EOF packets to the client until we reached the end of
the current statement.
This is a consolidation, to keep the functionality that is shared by all
SQL statements in one place in the server.
Currently this functionality includes:
- close_thread_tables()
- log_slow_statement().
After this patch and the subsequent patch for Bug#12713, it shall also include:
- ha_autocommit_or_rollback()
- net_end_statement()
- query_cache_end_of_result().
In future it may also include:
- mysql_reset_thd_for_next_command().
There were two problems when inferring the correct field types resulting from
UNION queries.
- If the type is NULL for all corresponding fields in the UNION, the resulting
type would be NULL, while the type is BINARY(0) if there is just a single
SELECT NULL.
- If one SELECT in the UNION uses a subselect, a temporary table is created
to represent the subselect, and the result type defaults to a STRING type,
hiding the fact that the type was unknown(just a NULL value).
Fixed by remembering whenever a field was created from a NULL value and pass
type NULL to the type coercion if that is the case, and creating a string field
as result of UNION only if the type would otherwise be NULL.
