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.
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.
Even though it returns NULL, the MAKETIME function did not have this property set,
causing a failed assertion (designed to catch exactly this).
Fixed by setting the nullability property of MAKETIME().
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.
Item_sum_distinct::setup(THD*): Assertion
There was an assertion to detect a bug in ROLLUP
implementation. However the assertion is not true
when used in a subquery context with non-cacheable
statements.
Fixed by turning the assertion to accepted case
(just like it's done for the other aggregate functions).
when a divisor is less than 1 and its fractional part is very long.
For example:
1 % .123456789123456789123456789123456789123456789123456789123456789123456789123456789;
Stack buffer overflow has been fixed in the do_div_mod function.
A rule was introduced by the 5.1 part of the fix for bug 27531 to
prefer filesort over indexed ORDER BY when accessing all of the rows of a
table (because it's faster). This new rule was not accounting for the
presence of a LIMIT clause.
Fixed the condition for this rule so it will prefer filesort over
indexed ORDER BY only if no LIMIT.
when used in a VIEW.
The problem was that wrong function (create_tmp_from_item())
was used to create a temporary field for Item_func_sp.
The fix is to use create_tmp_from_field().
Problem: creating an rb-tree key we store length (2 bytes) before the actual data for
varchar key parts. The fact was missed for NULL key parts, when we set NULL byte and
skip the rest.
Fix: take into account the length of the varchar key parts for NULLs.
