drop table if exists t1,t2;
create table t1 (i int, j int, empty_string char(10), bool char(1), d date);
insert into t1 values (1,2,"","Y","2002-03-03"), (3,4,"","N","2002-03-04"), (5,6,"","Y","2002-03-04"), (7,8,"","N","2002-03-05");
select count(*) from t1 procedure analyse();
Field_name	Min_value	Max_value	Min_length	Max_length	Empties_or_zeros	Nulls	Avg_value_or_avg_length	Std	Optimal_fieldtype
count(*)	4	4	1	1	0	0	4.0000	0.0000	ENUM('4') NOT NULL
select * from t1 procedure analyse();
Field_name	Min_value	Max_value	Min_length	Max_length	Empties_or_zeros	Nulls	Avg_value_or_avg_length	Std	Optimal_fieldtype
test.t1.i	1	7	1	1	0	0	4.0000	2.2361	ENUM('1','3','5','7') NOT NULL
test.t1.j	2	8	1	1	0	0	5.0000	2.2361	ENUM('2','4','6','8') NOT NULL
test.t1.empty_string			0	0	4	0	0.0000	NULL	CHAR(0) NOT NULL
test.t1.bool	N	Y	1	1	0	0	1.0000	NULL	ENUM('N','Y') NOT NULL
test.t1.d	2002-03-03	2002-03-05	10	10	0	0	10.0000	NULL	ENUM('2002-03-03','2002-03-04','2002-03-05') NOT NULL
select * from t1 procedure analyse(2);
Field_name	Min_value	Max_value	Min_length	Max_length	Empties_or_zeros	Nulls	Avg_value_or_avg_length	Std	Optimal_fieldtype
test.t1.i	1	7	1	1	0	0	4.0000	2.2361	TINYINT(1) UNSIGNED NOT NULL
test.t1.j	2	8	1	1	0	0	5.0000	2.2361	TINYINT(1) UNSIGNED NOT NULL
test.t1.empty_string			0	0	4	0	0.0000	NULL	CHAR(0) NOT NULL
test.t1.bool	N	Y	1	1	0	0	1.0000	NULL	ENUM('N','Y') NOT NULL
test.t1.d	2002-03-03	2002-03-05	10	10	0	0	10.0000	NULL	ENUM('2002-03-03','2002-03-04','2002-03-05') NOT NULL
create table t2 select * from t1 procedure analyse();
select * from t2;
Field_name	Min_value	Max_value	Min_length	Max_length	Empties_or_zeros	Nulls	Avg_value_or_avg_length	Std	Optimal_fieldtype
test.t1.i	1	7	1	1	0	0	4.0000	2.2361	ENUM('1','3','5','7') NOT NULL
test.t1.j	2	8	1	1	0	0	5.0000	2.2361	ENUM('2','4','6','8') NOT NULL
test.t1.empty_string			0	0	4	0	0.0000	NULL	CHAR(0) NOT NULL
test.t1.bool	N	Y	1	1	0	0	1.0000	NULL	ENUM('N','Y') NOT NULL
test.t1.d	2002-03-03	2002-03-05	10	10	0	0	10.0000	NULL	ENUM('2002-03-03','2002-03-04','2002-03-05') NOT NULL
drop table t1,t2;
EXPLAIN SELECT 1 FROM (SELECT 1) a PROCEDURE ANALYSE();
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	<derived2>	system	NULL	NULL	NULL	NULL	1	
2	DERIVED	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
