SQL语句修改字段默认值 mysql数据库,将temp表中,dept_id字段的默认值修改为0。alter table temp add constraint DEFAULT(0) for dept_id总是报有语法错误,谁能帮我看看呀 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 alter table table1modify column 类型 default 新的默认值; mysql> alter table users modify id int default 10;Database changedRecords: 0 Duplicates: 0 Warnings: 0mysql> describe users;+---------+-------------+------+-----+---------+-------+| Field | Type | Null | Key | Default | Extra |+---------+-------------+------+-----+---------+-------+| id | int(11) | NO | PRI | 10 | || name | varchar(20) | YES | | NULL | || age | int(11) | YES | | NULL | || tel | varchar(20) | YES | | NULL | || address | varchar(50) | YES | | NULL | |+---------+-------------+------+-----+---------+-------+5 rows in setmysql> mysql> desc t1;+-------+---------+------+-----+---------+-------+| Field | Type | Null | Key | Default | Extra |+-------+---------+------+-----+---------+-------+| id | int(11) | YES | | NULL | || f1 | int(11) | YES | | NULL | |+-------+---------+------+-----+---------+-------+2 rows in set (0.41 sec)mysql> alter table t1 modify f1 int default 10;Query OK, 0 rows affected (0.08 sec)Records: 0 Duplicates: 0 Warnings: 0mysql> desc t1;+-------+---------+------+-----+---------+-------+| Field | Type | Null | Key | Default | Extra |+-------+---------+------+-----+---------+-------+| id | int(11) | YES | | NULL | || f1 | int(11) | YES | | 10 | |+-------+---------+------+-----+---------+-------+2 rows in set (0.02 sec)mysql> mysql中的longtext问题 oracle语句转mysql 求一个sql,搜索比某条记录数少的第一条记录。 sql语句中的一个疑惑 mysql auto_increment 的问题 csv如何导入 mysql? ACMAIN_CHM 来帮帮忙。。 存储过程总提示错误... 请问如何在SQL表中设置触发器,使到字段自动加1!!多谢了!!!! eeeee 可以通过哪些方面优化 mysql中文查询得不到结果 postgresql能否把一个数组转换成表结构?
alter table table1modify column 类型 default 新的默认值;
mysql> alter table users modify id int default 10;
Database changed
Records: 0 Duplicates: 0 Warnings: 0
mysql> describe users;
+---------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------+-------------+------+-----+---------+-------+
| id | int(11) | NO | PRI | 10 | |
| name | varchar(20) | YES | | NULL | |
| age | int(11) | YES | | NULL | |
| tel | varchar(20) | YES | | NULL | |
| address | varchar(50) | YES | | NULL | |
+---------+-------------+------+-----+---------+-------+
5 rows in setmysql>
+-------+---------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+---------+------+-----+---------+-------+
| id | int(11) | YES | | NULL | |
| f1 | int(11) | YES | | NULL | |
+-------+---------+------+-----+---------+-------+
2 rows in set (0.41 sec)mysql> alter table t1 modify f1 int default 10;
Query OK, 0 rows affected (0.08 sec)
Records: 0 Duplicates: 0 Warnings: 0mysql> desc t1;
+-------+---------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+---------+------+-----+---------+-------+
| id | int(11) | YES | | NULL | |
| f1 | int(11) | YES | | 10 | |
+-------+---------+------+-----+---------+-------+
2 rows in set (0.02 sec)mysql>