方法一、使用add constraint 方法添加主键约束 alter table 表名 add constraint 主键名 primary key (列名1,列名2,...) 方法二、使用索引创建主键 (和方法一没有区别,可以将方法一理解为省略了using index) alter table 表名 add constraint 主键名 primary key (列名1,列名2,...) using index [index_name...
1.语法:ALTER TABLE 表名 ADD CONSTRAINT 主键名 PRIMARY KEY 表名(主键字段); 3.添加外键 1.语法:ALTER TABLE 表名 ADD CONNSTRAINT 外键名 FOREIGN KEY(外键字段) REFERENCES 关联表名(关联字段); 4.插入单(多)条数据记录(和SQL Server相同,但是不能用select多列添加数据) 1.INSERT INTO 表名[(字段名...
http://stackoverflow.com/questions/4668146/how-to-add-a-primary-key-on-a-oracle-view It allows them, but only in a disabled state. They provide information to the optimiser but cannot be enforced. –Tony AndrewsJan 12 '11 at 12:55 Exactly what Tony said. And some tools that do object...
1.主键约束:列被约束为(非空、不重复) 格式:alter table 表格名称 add constraint 约束名称 primary key (列名) 例子:alter table emp add constraint ppp primary key (id); 2.外键约束:列被约束为引用其他表的主键 格式:alter table 表名 add constraint 约束名称 foreign key (列名) references 被引用的表...
ADD CONSTRAINT pk_employee PRIMARY KEY (emp_id), ADD CONSTRAINT uk_employee UNIQUE (emp_name); 其中,pk_employee表示主键约束的名称,emp_id表示主键列名;uk_employee表示唯一约束的名称,emp_name表示唯一约束列名。 2. 修改约束 在Oracle数据库中,我们也可以使用ALTER TABLE语句来修改已有的约束。具体语法如下...
Bug #101677 Add primary key error: error 1265 (01000): Data truncated for column Submitted: 19 Nov 2020 10:34Modified: 20 Nov 2020 7:09 Reporter: yang li Email Updates: Status: Not a Bug Impact on me: None Category: MySQL Server: DDLSeverity: S3 (Non-critical) Version: 8.0OS: ...
Description Adding primary key column in older versions of Oracle and in 12c Area SQL General / DDL Contributor Andrew Clarke Created Tuesday December 26, 2017 Statement 1 create table t23 (EMP_NAME varchar2(20), EMP_POS varchar2(20), SALARY number, GENDER varchar2(1)) Table created...
Oracle中使用ADD CONSTRAINT语句来添加约束。具体用法如下: 1.添加主键约束: ALTER TABLE table_name ADD CONSTRAINT pk_constraint PRIMARY KEY (column1, column2, ...); 2.添加唯一约束: ALTER TABLE table_name ADD CONSTRAINT unique_constraint UNIQUE (column1, column2, ...); 3.添加外键约束: ALTER ...
//lists.mysql.com/commits/1309663313 Jimmy Yang 2011-02-10 Merge a fix forBug #53756ALTER TABLE ADD PRIMARY KEY affects crash recovery This was already pushed to mysql-5.1-innodb some time ago (revision id jimmy.yang@oracle.com-20100907054137-tpuior7hez4f5ghl) but it was not merged to ...
Modify, drop, and add constraints,ApsaraDB for OceanBase:This topic describes the conversion scope of constraint modification, dropping, and addition in ALTER TABLE DDL operations during data migration from an Oracle database to an Oracle tenant of Ocean