when learning the database, I tapped at the code in the book, but it couldn"t be implemented. I checked the source code and found no errors.
as shown in the picture, this is the content of the book:
:
:
:
:
this is the result even if you enter it in the terminal, which means it"s not the software, it"s the code itself, but the code itself is automatically generated by the software, so I can"t understand it. What"s wrong with
?
gender field length
may be a character set encoding problem. Take a look at this
sex field to varchar
show variables like'% character%'; take a look at the default encoding. For the lower version of MySQL , the default encoding is latin1 , which is not supported in Chinese. Just change it to utf8 .
latin1:
db83-3306>>CREATE TABLE `test_c` (
-> `studentNo` int(4) NOT NULL COMMENT '',
-> `loginPwd` varchar(20) NOT NULL COMMENT '',
-> `studentName` varchar(50) NOT NULL COMMENT '',
-> `sex` char(2) NOT NULL DEFAULT '' COMMENT '',
-> `gradeId` int(4) NULL COMMENT '',
-> `phone` varchar(50) NULL COMMENT '',
-> `address` varchar(255) NULL DEFAULT '' COMMENT '',
-> `bornDate` datetime(0) NULL COMMENT '',
-> `email` varchar(50) NULL COMMENT '',
-> `identityCard` varchar(18) NULL COMMENT '',
-> PRIMARY KEY (`studentNo`),
-> UNIQUE INDEX `n_identityCard`(`identityCard`(18))
-> ) CHARSET=latin1 COMMENT = '';
ERROR 1067 (42000): Invalid default value for 'sex'utf8:
db83-3306>>CREATE TABLE `test_c` (
-> `studentNo` int(4) NOT NULL COMMENT '',
-> `loginPwd` varchar(20) NOT NULL COMMENT '',
-> `studentName` varchar(50) NOT NULL COMMENT '',
-> `sex` char(2) NOT NULL DEFAULT '' COMMENT '',
-> `gradeId` int(4) NULL COMMENT '',
-> `phone` varchar(50) NULL COMMENT '',
-> `address` varchar(255) NULL DEFAULT '' COMMENT '',
-> `bornDate` datetime(0) NULL COMMENT '',
-> `email` varchar(50) NULL COMMENT '',
-> `identityCard` varchar(18) NULL COMMENT '',
-> PRIMARY KEY (`studentNo`),
-> UNIQUE INDEX `n_identityCard`(`identityCard`(18))
-> ) CHARSET=utf8 COMMENT = '';
Query OK, 0 rows affected (0.02 sec)Previous: Phpword template cannot modify picture
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