DROP TABLE IF EXISTS t1;
CREATE TABLE t1 (t TEXT <CUSTOM_COL_OPTIONS>,
t0 TEXT(0) <CUSTOM_COL_OPTIONS>,
t1 TEXT(1) <CUSTOM_COL_OPTIONS>,
t300 TEXT(300) <CUSTOM_COL_OPTIONS>,
tm TEXT(65535) <CUSTOM_COL_OPTIONS>,
t70k TEXT(70000) <CUSTOM_COL_OPTIONS>,
t17m TEXT(17000000) <CUSTOM_COL_OPTIONS>,
tt TINYTEXT <CUSTOM_COL_OPTIONS>,
m MEDIUMTEXT <CUSTOM_COL_OPTIONS>,
l LONGTEXT <CUSTOM_COL_OPTIONS>
) ENGINE=<STORAGE_ENGINE> <CUSTOM_TABLE_OPTIONS>;
SHOW COLUMNS IN t1;
Field	Type	Null	Key	Default	Extra
t	text	#	#	#	
t0	text	#	#	#	
t1	tinytext	#	#	#	
t300	text	#	#	#	
tm	text	#	#	#	
t70k	mediumtext	#	#	#	
t17m	longtext	#	#	#	
tt	tinytext	#	#	#	
m	mediumtext	#	#	#	
l	longtext	#	#	#	
INSERT INTO t1 (t,t0,t1,t300,tm,t70k,t17m,tt,m,l) VALUES
('','','','','','','','','',''),
('a','b','c','d','e','f','g','h','i','j'),
('test1','test2','test3','test4','test5','test6','test7','test8','test9','test10'),
( REPEAT('a',65535), REPEAT('b',65535), REPEAT('c',255), REPEAT('d',65535), REPEAT('e',65535), REPEAT('f',1048576), REPEAT('g',1048576), REPEAT('h',255), REPEAT('i',1048576), REPEAT('j',1048576) );
SELECT LENGTH(t), LENGTH(t0), LENGTH(t1), LENGTH(t300), LENGTH(tm), LENGTH(t70k), LENGTH(t17m), LENGTH(tt), LENGTH(m), LENGTH(l) FROM t1;
LENGTH(t)	LENGTH(t0)	LENGTH(t1)	LENGTH(t300)	LENGTH(tm)	LENGTH(t70k)	LENGTH(t17m)	LENGTH(tt)	LENGTH(m)	LENGTH(l)
0	0	0	0	0	0	0	0	0	0
1	1	1	1	1	1	1	1	1	1
5	5	5	5	5	5	5	5	5	6
65535	65535	255	65535	65535	1048576	1048576	255	1048576	1048576
INSERT INTO t1 (t,t0,t1,t300,tm,t70k,t17m,tt,m,l) VALUES
( REPEAT('a',65536), REPEAT('b',65536), REPEAT('c',256), REPEAT('d',65536), REPEAT('e',65536), REPEAT('f',1048576), REPEAT('g',1048576), REPEAT('h',256), REPEAT('i',1048576), REPEAT('j',1048576) );
Warnings:
Warning	1265	Data truncated for column 't' at row 1
Warning	1265	Data truncated for column 't0' at row 1
Warning	1265	Data truncated for column 't1' at row 1
Warning	1265	Data truncated for column 't300' at row 1
Warning	1265	Data truncated for column 'tm' at row 1
Warning	1265	Data truncated for column 'tt' at row 1
SELECT LENGTH(t), LENGTH(t0), LENGTH(t1), LENGTH(t300), LENGTH(tm), LENGTH(t70k), LENGTH(t17m), LENGTH(tt), LENGTH(m), LENGTH(l) FROM t1;
LENGTH(t)	LENGTH(t0)	LENGTH(t1)	LENGTH(t300)	LENGTH(tm)	LENGTH(t70k)	LENGTH(t17m)	LENGTH(tt)	LENGTH(m)	LENGTH(l)
0	0	0	0	0	0	0	0	0	0
1	1	1	1	1	1	1	1	1	1
5	5	5	5	5	5	5	5	5	6
65535	65535	255	65535	65535	1048576	1048576	255	1048576	1048576
65535	65535	255	65535	65535	1048576	1048576	255	1048576	1048576
ALTER TABLE t1 ADD COLUMN ttt TEXT(4294967296);
ERROR 42000: Display width out of range for 'ttt' (max = 4294967295)
DROP TABLE t1;