the result takes its charset/collation
attributes from the character string,
e.g. SELECT func(NULL, _latin2'string')
now returns a latin2 result. This is
done by introducing a new derivation
(aka coercibility) level DERIVATION_IGNORABLE,
which is used with Item_null.
2. 'Pure' NULL is now BINARY(0), not CHAR(0).
I.e. NULL is now more typeless.
character set with NULL, @a should be latin2
after this query sequence:
SET @a=_latin2'string';
SET @a=NULL;
I.e. the second query should not change the charset
to the current default value, but should keep the
original value assigned during the first query.
In order to do it, we don't copy charset
from the argument if the argument is NULL
and the variable has previously been initialized.
if possible"
- many new test cases
- more and improved comments
New files: t/ps_7ndb.test test suite for NDB tables
r/ps_7ndb.result expected results
include/ps_conv.inc conversion test cases
+ review comments and fixes.