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DROP TABLE IF EXISTS t1;
SET NAMES cp932;
create table t1 (c1 VARCHAR(10) NOT NULL COMMENT ' ', c2 INTEGER,c3 INTEGER COMMENT '', c4 INTEGER, c5 INTEGER, c6 INTEGER, c7 INTEGER, INDEX i1 (c1) COMMENT 'i1 comment',INDEX i2(c2)
) COMMENT='';
SELECT table_comment,char_length(table_comment) FROM information_schema.tables WHERE table_name='t1';
table_comment char_length(table_comment)
1024
SELECT column_comment,char_length(column_comment) FROM information_schema.columns WHERE table_name='t1';
column_comment char_length(column_comment)
11
0
300
0
0
0
0
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c1` varchar(10) NOT NULL COMMENT ' ',
`c2` int(11) DEFAULT NULL,
`c3` int(11) DEFAULT NULL COMMENT '',
`c4` int(11) DEFAULT NULL,
`c5` int(11) DEFAULT NULL,
`c6` int(11) DEFAULT NULL,
`c7` int(11) DEFAULT NULL,
KEY `i1` (`c1`) COMMENT 'i1 comment',
KEY `i2` (`c2`)
) ENGINE=ENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci COMMENT=''
drop table t1;
create table t1 (c1 VARCHAR(10) NOT NULL COMMENT 'c1 comment', c2 INTEGER,c3 INTEGER COMMENT '', c4 INTEGER, c5 INTEGER, c6 INTEGER, c7 INTEGER, INDEX i1 (c1) COMMENT 'i1 comment',INDEX i2(c2)
) COMMENT='';
SELECT table_comment,char_length(table_comment) FROM information_schema.tables WHERE table_name='t1';
table_comment char_length(table_comment)
1025
SELECT column_comment,char_length(column_comment) FROM information_schema.columns WHERE table_name='t1';
column_comment char_length(column_comment)
c1 comment 10
0
300
0
0
0
0
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c1` varchar(10) NOT NULL COMMENT 'c1 comment',
`c2` int(11) DEFAULT NULL,
`c3` int(11) DEFAULT NULL COMMENT '',
`c4` int(11) DEFAULT NULL,
`c5` int(11) DEFAULT NULL,
`c6` int(11) DEFAULT NULL,
`c7` int(11) DEFAULT NULL,
KEY `i1` (`c1`) COMMENT 'i1 comment',
KEY `i2` (`c2`)
) ENGINE=ENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci COMMENT=''
drop table t1;
set sql_mode='';
create table t1 (c1 VARCHAR(10) NOT NULL COMMENT 'c1 comment', c2 INTEGER,c3 INTEGER COMMENT '', c4 INTEGER, c5 INTEGER, c6 INTEGER, c7 INTEGER, INDEX i1 (c1) COMMENT 'i1 comment',INDEX i2(c2)
) COMMENT='';
SELECT table_comment,char_length(table_comment) FROM information_schema.tables WHERE table_name='t1';
table_comment char_length(table_comment)
2048
SELECT column_comment,char_length(column_comment) FROM information_schema.columns WHERE table_name='t1';
column_comment char_length(column_comment)
c1 comment 10
0
300
0
0
0
0
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c1` varchar(10) NOT NULL COMMENT 'c1 comment',
`c2` int(11) DEFAULT NULL,
`c3` int(11) DEFAULT NULL COMMENT '',
`c4` int(11) DEFAULT NULL,
`c5` int(11) DEFAULT NULL,
`c6` int(11) DEFAULT NULL,
`c7` int(11) DEFAULT NULL,
KEY `i1` (`c1`) COMMENT 'i1 comment',
KEY `i2` (`c2`)
) ENGINE=ENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci COMMENT=''
drop table t1;
set sql_mode='';
create table t1 (c1 VARCHAR(10) NOT NULL COMMENT 'c1 comment', c2 INTEGER,c3 INTEGER COMMENT '', c4 INTEGER, c5 INTEGER, c6 INTEGER, c7 INTEGER, INDEX i1 (c1) COMMENT 'i1 comment',INDEX i2(c2)
) COMMENT='';
Warnings:
Warning 1628 Comment for table 't1' is too long (max = 2048)
SELECT table_comment,char_length(table_comment) FROM information_schema.tables WHERE table_name='t1';
table_comment char_length(table_comment)
2048
SELECT column_comment,char_length(column_comment) FROM information_schema.columns WHERE table_name='t1';
column_comment char_length(column_comment)
c1 comment 10
0
300
0
0
0
0
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c1` varchar(10) NOT NULL COMMENT 'c1 comment',
`c2` int(11) DEFAULT NULL,
`c3` int(11) DEFAULT NULL COMMENT '',
`c4` int(11) DEFAULT NULL,
`c5` int(11) DEFAULT NULL,
`c6` int(11) DEFAULT NULL,
`c7` int(11) DEFAULT NULL,
KEY `i1` (`c1`) COMMENT 'i1 comment',
KEY `i2` (`c2`)
) ENGINE=ENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci COMMENT=''
drop table t1;
set sql_mode='TRADITIONAL';
create table t1 (c1 VARCHAR(10) NOT NULL COMMENT 'c1 comment', c2 INTEGER,c3 INTEGER COMMENT '', c4 INTEGER, c5 INTEGER, c6 INTEGER, c7 INTEGER, INDEX i1 (c1) COMMENT 'i1 comment',INDEX i2(c2)
) COMMENT='';
ERROR HY000: Comment for table 't1' is too long (max = 2048)
SELECT table_comment,char_length(table_comment) FROM information_schema.tables WHERE table_name='t1';
table_comment char_length(table_comment)
SELECT column_comment,char_length(column_comment) FROM information_schema.columns WHERE table_name='t1';
column_comment char_length(column_comment)
|
