Bug#29816 Syntactically wrong query fails with misleading error message
The core problem is that an SQL-invoked function name can be a <schema
qualified routine name> that contains no <schema name>, but the mysql
parser insists that all stored procedures (function, procedures and
triggers) must have a <schema name>, which is not true for functions.
This problem is especially visible when trying to create a function
or when a query contains a syntax error after a function call (in the
same query), both will fail with a "No database selected" message if
the session is not attached to a particular schema, but the first
one should succeed and the second fail with a "syntax error" message.
Part of the fix is to revamp the sp name handling so that a schema
name may be omitted for functions -- this means that the internal
function name representation may not have a dot, which represents
that the function doesn't have a schema name. The other part is
to place schema checks after the type (function, trigger or procedure)
of the routine is known.
This deadlock occurs when a client issues a HANDLER ... OPEN statement
that tries to open a table that has a pending name-lock on it by another
client that also needs a name-lock on some other table which is already
open and associated to a HANDLER instance owned by the first client.
The deadlock happens because the open_table() function will back-off
and wait until the name-lock goes away, causing a circular wait if some
other name-lock is also pending for one of the open HANDLER tables.
Such situation, for example, can be easily repeated by issuing a RENAME
TABLE command in such a way that the existing table is already open
as a HANDLER table by another client and this client tries to open
a HANDLER to the new table name.
The solution is to allow handler tables with older versions (marked for
flush) to be closed before waiting for the name-lock completion. This is
safe because no other name-lock can be issued between the flush and the
check for pending name-locks.
The test case for this bug is going to be committed into 5.1 because it
requires a test feature only avaiable in 5.1 (wait_condition).
Problem: creating a partitioned table during name resolution for the
partition function we search for column names in all parts of the
CREATE TABLE query. It is superfluous (and wrong) sometimes.
Fix: launch name resolution for the partition function against
the table we're creating.
bitmap_is_set(table->write_set, fiel
Problem: creating a temporary table we allocate the group buffer if needed
followed by table bitmaps (see create_tmp_table()). Reserving less memory for
the group buffer than actually needed (used) for values retrieval may lead
to overlapping with followed bitmaps in the memory pool that in turn leads
to unpredictable consequences.
As we use Item->max_length sometimes to calculate group buffer size,
it must be set to proper value. In this particular case
Item_datetime_typecast::max_length is too small.
Another problem is that we use max_length to calculate the group buffer
key length for items represented as DATE/TIME fields which is superfluous.
Fix: set Item_datetime_typecast::max_length properly,
accurately calculate the group buffer key length for items
represented as DATE/TIME fields in the buffer.
