外键foreign key:对关系字段进行约束,当为关系字段填写值时,会到关联的表中查询此值是否存在,如果存在则填写成功,如果不存在则填写失败并抛出异常 check(expr):用于定义检查性约束 [comment 'string']:设置字段的描述信息,此设置可省 {index|key}:定义索引 {fulltext|spatial}:全文索引和空间索引 例子: --创建cl...
create table repo_table( repo_id char(13) not null primary key, repo_name char(14) not null) type=innodb; 创建表2 mysql> create table busi_table( -> busi_id char(13) not null primary key, -> busi_name char(13) not null, -> repo_id char(13) not null, -> foreign key(repo_...
create table repo_table( repo_id char(13) not null primary key, repo_name char(14) not null) type=innodb; 创建表2 mysql> create table busi_table( -> busi_id char(13) not null primary key, -> busi_name char(13) not null, -> repo_id char(13) not null, -> foreign key(repo_...
repo_id char(13) not null primary key, repo_name char(14) not null) type=innodb; 创建表2 mysql> create table busi_table( -> busi_id char(13) not null primary key, -> busi_name char(13) not null, -> repo_id char(13) not null, -> foreign key(repo_id) references repo_table...
为表student添加外键约束,具体语句如下:mysql> alter table student add constraint FK_ID foreign key gid references grade id; ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'references gra...
http://www.cppblog.com/wolf/articles/69089.html 【4】mysql官网英文网站 http://dev.mysql.com/doc/refman/5.5/en/innodb-foreign-key-constraints.html 中文网站 http://dev.mysql.com/doc/refman/5.1/zh/sql-syntax.html 【5】 对外键讲解的比较全面,可以一读...
Name: ‘CREATE TABLE’Description:Syntax:CREATE [TEMPORARY] TABLE [IF NOT EXISTS] tbl_name(create_definition,…)[table_options]CREATE [TEMPORARY] TABLE [IF NOT EXISTS] tbl_name[(create_definition,…)][table_options][partition_options][IGNORE | REPLACE][AS] query_expressionCREATE [TEMPORARY] ...
9.1.4.2 The Relationship Editor 9.1.4.3 Connection Properties Foreign key constraints are supported for theInnoDBstorage engine only. For other storage engines, the foreign key syntax is correctly parsed but not implemented. For more information, seeFOREIGN KEY Constraint Differences. ...
MySQL FOREIGN KEY Constraints ALTER TABLE Syntax 通过以上步骤和示例代码,可以有效地修改MySQL中的外键约束和列。 相关搜索: mysql 修改外键关系 mysql 修改外键类型 mysql 修改外键为级联 mysql 修改外键的值 mysql修改外键引用表 mysql修改表取消外键 mysql 修改外键引用表 mysql修改表的外键 mysql修改表取消外键约束...
This syntax creates a column; it does not create any sort of index or key. You can use a column so created as a join column, as shown here: CREATE TABLE person ( id SMALLINT UNSIGNED NOT NULL AUTO_INCREMENT, name CHAR(60) NOT NULL, PRIMARY KEY (id) ); CREATE TABLE shirt ( ...