diff options
| -rw-r--r-- | mysql-test/r/group_by.result | 10 | ||||
| -rw-r--r-- | mysql-test/t/group_by.test | 15 | ||||
| -rw-r--r-- | sql/item_buff.cc | 4 |
3 files changed, 27 insertions, 2 deletions
diff --git a/mysql-test/r/group_by.result b/mysql-test/r/group_by.result index e279fca2a9d..7f78b8bda9b 100644 --- a/mysql-test/r/group_by.result +++ b/mysql-test/r/group_by.result @@ -741,3 +741,13 @@ SELECT dt DIV 1 AS f, id FROM t1 GROUP BY f; f id 20050501123000 1 DROP TABLE t1; +CREATE TABLE t1 (id varchar(20) NOT NULL); +INSERT INTO t1 VALUES ('trans1'), ('trans2'); +CREATE TABLE t2 (id varchar(20) NOT NULL, err_comment blob NOT NULL); +INSERT INTO t2 VALUES ('trans1', 'a problem'); +SELECT COUNT(DISTINCT(t1.id)), LEFT(err_comment, 256) AS err_comment +FROM t1 LEFT JOIN t2 ON t1.id=t2.id GROUP BY err_comment; +COUNT(DISTINCT(t1.id)) err_comment +1 NULL +1 a problem +DROP TABLE t1, t2; diff --git a/mysql-test/t/group_by.test b/mysql-test/t/group_by.test index 382580cbd4e..694aa8d7411 100644 --- a/mysql-test/t/group_by.test +++ b/mysql-test/t/group_by.test @@ -565,3 +565,18 @@ INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' ); SELECT dt DIV 1 AS f, id FROM t1 GROUP BY f; DROP TABLE t1; + +# +# Test for bug #11295: GROUP BY a BLOB column with COUNT(DISTINCT column1) +# when the BLOB column takes NULL values +# + +CREATE TABLE t1 (id varchar(20) NOT NULL); +INSERT INTO t1 VALUES ('trans1'), ('trans2'); +CREATE TABLE t2 (id varchar(20) NOT NULL, err_comment blob NOT NULL); +INSERT INTO t2 VALUES ('trans1', 'a problem'); + +SELECT COUNT(DISTINCT(t1.id)), LEFT(err_comment, 256) AS err_comment + FROM t1 LEFT JOIN t2 ON t1.id=t2.id GROUP BY err_comment; + +DROP TABLE t1, t2; diff --git a/sql/item_buff.cc b/sql/item_buff.cc index f5e77862e1d..8298ce2cfb7 100644 --- a/sql/item_buff.cc +++ b/sql/item_buff.cc @@ -51,8 +51,8 @@ bool Item_str_buff::cmp(void) String *res; bool tmp; - res=item->val_str(&tmp_value); - res->length(min(res->length(), value.alloced_length())); + if ((res=item->val_str(&tmp_value))) + res->length(min(res->length(), value.alloced_length())); if (null_value != item->null_value) { if ((null_value= item->null_value)) |