Commit 3ad8b4c1 authored by unknown's avatar unknown
Browse files

row0sel.c: 

  Fix bug number 154: GROUP BY and DISTINCT could treat NULL values inequal


innobase/row/row0sel.c:
  Fix bug number 154: GROUP BY and DISTINCT could treat NULL values inequal
parent d8ea9fc9

innobase/row/row0sel.c

+8 −13
Original line number Diff line number Diff line
@@ -2115,19 +2115,14 @@ row_sel_store_mysql_rec( 
				extern_field_heap = NULL;

 			}

		} else {

			/* MySQL sometimes seems to copy the 'data'

			pointed to by a BLOB field even if the field

			has been marked to contain the SQL NULL value.

			This caused seg faults reported by two users.

			Set the BLOB length to 0 and the data pointer

			to NULL to avoid a seg fault. */



			if (templ->type == DATA_BLOB) {

				row_sel_field_store_in_mysql_format(

				mysql_rec + templ->mysql_col_offset,

				templ->mysql_col_len, NULL,

				0, templ->type, templ->is_unsigned);

			}

		        /* MySQL seems to assume the field for an SQL NULL

		        value is set to zero. Not taking this into account

		        caused seg faults with NULL BLOB fields, and

		        bug number 154 in the MySQL bug database: GROUP BY

		        and DISTINCT could treat NULL values inequal. */



		        memset(mysql_rec + templ->mysql_col_offset, '\0',

			       templ->mysql_col_len);



			if (!templ->mysql_null_bit_mask) {

				fprintf(stderr,