#
# Check null keys

drop table if exists t1;
create table t1 (a int, b int not null,unique key (a,b),index(b)) type=myisam;
insert ignore into t1 values (1,1),(2,2),(3,3),(4,4),(5,5),(6,6),(null,7),(9,9),(8,8),(7,7),(null,9),(null,9),(6,6);
explain select * from t1 where a is null;
explain select * from t1 where a is null and b = 2;
explain select * from t1 where a is null and b = 7;
explain select * from t1 where a=2 and b = 2;
explain select * from t1 where a<=>b limit 2;
explain select * from t1 where (a is null or a > 0 and a < 3) and b < 5 limit 3;
explain select * from t1 where (a is null or a = 7) and b=7;
explain select * from t1 where (a is null and b>a) or a is null and b=7 limit 2;
explain select * from t1 where a is null and b=9 or a is null and b=7 limit 3;
explain select * from t1 where a > 1 and a < 3 limit 1;
explain select * from t1 where a > 8 and a < 9;
select * from t1 where a is null;
select * from t1 where a is null and b = 7;
select * from t1 where a<=>b limit 2;
select * from t1 where (a is null or a > 0 and a < 3) and b < 5 limit 3;
select * from t1 where (a is null or a > 0 and a < 3) and b > 7 limit 3;
select * from t1 where (a is null or a = 7) and b=7;
select * from t1 where a is null and b=9 or a is null and b=7 limit 3;
alter table t1 modify b blob not null, add c int not null, drop key a, add unique key (a,b(20),c), drop key b, add key (b(10));
explain select * from t1 where a is null and b = 2;
explain select * from t1 where a is null and b = 2 and c=0;
explain select * from t1 where a is null and b = 7 and c=0;
explain select * from t1 where a=2 and b = 2;
explain select * from t1 where a<=>b limit 2;
explain select * from t1 where (a is null or a > 0 and a < 3) and b < 5 and c=0 limit 3;
explain select * from t1 where (a is null or a = 7) and b=7 and c=0;
explain select * from t1 where (a is null and b>a) or a is null and b=7 limit 2;
explain select * from t1 where a is null and b=9 or a is null and b=7 limit 3;
explain select * from t1 where a > 1 and a < 3 limit 1;
explain select * from t1 where a is null and b=7 or a > 1 and a < 3 limit 1;
explain select * from t1 where a > 8 and a < 9;
explain select * from t1 where b like "6%";
select * from t1 where a is null;
select * from t1 where a is null and b = 7 and c=0;
select * from t1 where a<=>b limit 2;
select * from t1 where (a is null or a > 0 and a < 3) and b < 5 limit 3;
select * from t1 where (a is null or a > 0 and a < 3) and b > 7 limit 3;
select * from t1 where (a is null or a = 7) and b=7 and c=0;
select * from t1 where a is null and b=9 or a is null and b=7 limit 3;
select * from t1 where b like "6%";
drop table t1;


#
# The following failed for Matt Loschert
#

DROP TABLE IF EXISTS t1,t2;
CREATE TABLE t1 (
  id int(10) unsigned NOT NULL auto_increment,
  uniq_id int(10) unsigned default NULL,
  PRIMARY KEY  (id),
  UNIQUE KEY idx1 (uniq_id)
) TYPE=MyISAM;

CREATE TABLE t2 (
  id int(10) unsigned NOT NULL auto_increment,
  uniq_id int(10) unsigned default NULL,
  PRIMARY KEY  (id)
) TYPE=MyISAM;

INSERT INTO t1 VALUES (1,NULL),(2,NULL),(3,1),(4,2),(5,NULL),(6,NULL),(7,3),(8,4),(9,NULL),(10,NULL);
INSERT INTO t2 VALUES (1,NULL),(2,NULL),(3,1),(4,2),(5,NULL),(6,NULL),(7,3),(8,4),(9,NULL),(10,NULL);

#
# Check IS NULL optimization
#
explain select id from t1 where uniq_id is null;
explain select id from t1 where uniq_id =1;
#
# Check updates
#
UPDATE t1 SET id=id+100 where uniq_id is null;
UPDATE t2 SET id=id+100 where uniq_id is null;
select id from t1 where uniq_id is null;
select id from t2 where uniq_id is null;
#
# Delete all records from each table where the uniq_id field is null
#
DELETE FROM t1 WHERE uniq_id IS NULL;
DELETE FROM t2 WHERE uniq_id IS NULL;
#
# Select what is left -- notice the difference
#
SELECT * FROM t1 ORDER BY uniq_id, id;
SELECT * FROM t2 ORDER BY uniq_id, id;
DROP table t1,t2;