Navicat for SQL使用注意(设置默认字符集,外键保存不了)
最近用mysqlNavicat for sql开发项目时遇到了以下问题: 1.默认创建的数据库,字符集编码为:latin1 -- cp1252 West European 在数据库中存储中文时会出现乱码错误 2.用Navicat给数据库添加外键约束时,保存不了,保存后消失 解决方案: 1对于字符集问题有3
最近用mysql+Navicat for sql开发项目时遇到了以下问题:
1.默认创建的数据库,字符集编码为:latin1 -- cp1252 West European
在数据库中存储中文时会出现乱码错误
2.用Navicat给数据库添加外键约束时,保存不了,保存后消失
解决方案:
1对于字符集问题有3种解决方式,设置字段字符集,表的字符集,数据字符集
其中设置字段字符集,表的字符集方法较笨,需要一个一个的设置,这里就简要说明下:
在navicat中选择要操作的表,选择“设计”,将光标放置在要修改的字段上,即可在下方修改该字段的字符集
同上,选择”设计“后,在选项中可以看到字符集一栏,修改后就完成了表的字符集修改
最后说下修改数据库的默认字符集,修改数据库的默认字符集必须在创建数据库的时候完成,如果数据库中已存在其他字符集的表,字段,则修改不会生效
如下图,在新建数据库时设置字符集
2.对于外键约束保存不了或者保存后消失的,有两个原因
1)数据库的FOREIGN_KEY_CHECKS=0;所有外键约束被禁用了
查看当前FOREIGN_KEY_CHECKS的值可用如下命令
SELECT @@FOREIGN_KEY_CHECKS;
之后再用SET FOREIGN_KEY_CHECKS=1;
来启动外键约束.
2)在 MySQL 中只有 InnoDB 类型的表才支持外键与存储过程
所有要建立外键的字段必须建立索引
创建数据库时设置表类型为InnoDB
CREATE TABLE `roottb` (
`id` INT(11) UNSIGNED AUTO_INCREMENT NOT NULL,
`data` VARCHAR(100) NOT NULL DEFAULT '',
PRIMARY KEY (`id`)
) TYPE=InnoDB;
在Navicat中,新建表时,在选项中设置引擎为InnoDB

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