[英]How to add a where clause in a MySQL Insert statement?
This doesn't work: 这不起作用:
INSERT INTO users (username, password) VALUES ("Jack","123") WHERE id='1';
Any ideas how to narrow insertion to a particular row by id? 任何想法如何通过id将插入范围缩小到特定行?
In an insert statement you wouldn't have an existing row to do a where claues on? 在插入语句中,您将没有现有行来执行操作? You are inserting a new row, did you mean to do an update statment?
您要插入新行,是否意味着要执行更新语句?
update users set username='JACK' and password='123' WHERE id='1';
A conditional insert for use typically in a MySQL script would be: 通常在MySQL脚本中使用的条件插入为:
insert into t1(col1,col2,col3,...)
select val1,val2,val3,...
from dual
where [conditional predicate];
You need to use dummy table dual. 您需要使用双重虚拟表。
In this example, only the second insert-statement will actually insert data into the table: 在此示例中,仅第二个插入语句将实际将数据插入表中:
create table t1(col1 int);
insert into t1(col1) select 1 from dual where 1=0;
insert into t1(col1) select 2 from dual where 1=1;
select * from t1;
+------+
| col1 |
+------+
| 2 |
+------+
1 row in set (0.00 sec)
To add a WHERE clause inside an INSERT statement simply; 只需在INSERT语句内添加WHERE子句;
INSERT INTO table_name (column1,column2,column3)
SELECT column1, column2, column3 FROM table_name
WHERE column1 = 'some_value'
Try this: 尝试这个:
Update users
Set username = 'Jack', password='123'
Where ID = '1'
Or if you're actually trying to insert: 或者,如果您实际上是在尝试插入:
Insert Into users (id, username, password) VALUES ('1', 'Jack','123');
INSERT INTO users (id,username, password)
VALUES ('1','Jack','123')
ON DUPLICATE KEY UPDATE username='Jack',password='123'
This will work only if the id
field is unique/pk (not composite PK though) Also, this will insert if no id
of value 1 is found and update otherwise the record with id
1 if it does exists. 仅当
id
字段为唯一/ pk(尽管不是复合PK)时,此方法才有效。此外,如果未找到值为1的id
,则将插入该字段;如果存在,则更新id
1的记录。
UPDATE users SET username='&username', password='&password' where id='&id'
该查询将要求您动态输入用户名,密码和ID
For Empty row how we can insert values on where clause 对于空行,我们如何在where子句中插入值
Try this 尝试这个
UPDATE table_name SET username="",password="" WHERE id =""
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