如果存在，则插入到 MySQL 表或更新中

I want to add a row to a database table, but if a row exists with the same unique key I want to update the row.

For example,

insert into table (id, name, age) values(1, "A", 19)

Let’s say the unique key is id, and in my database there is a row with id = 1. In that case I want to update that row with these values. Normally this gives an error. If I use insert IGNORE it will ignore the error, but it still won’t update.

Use INSERT ... ON DUPLICATE KEY UPDATE

QUERY:

INSERT INTO table (id, name, age) VALUES(1, "A", 19) ON DUPLICATE KEY UPDATE    
name="A", age=19

Check out REPLACE

http://dev.mysql.com/doc/refman/5.0/en/replace.html

REPLACE into table (id, name, age) values(1, "A", 19)

Try this out:

INSERT INTO table (id, name, age) VALUES (1, 'A', 19) ON DUPLICATE KEY UPDATE id = id + 1;

Hope this helps.

Try this:

INSERT INTO table (id,name,age) VALUES('1','Mohammad','21') ON DUPLICATE KEY UPDATE name='Mohammad',age='21'

Note:
Here if id is the primary key then after first insertion with id='1' every time attempt to insert id='1' will update name and age and previous name age will change.

INSERT INTO table (id, name, age) VALUES (1, 'A', 19) ON DUPLICATE KEY UPDATE id = id + 1;

Also do not forget to concern about the unique key constraint.

ALTER TABLE `table` ADD UNIQUE `unique_key` ( `id` ) 

When using SQLite:

REPLACE into table (id, name, age) values(1, "A", 19)

Provided that id is the primary key. Or else it just inserts another row. See INSERT (SQLite).

Just because I was here looking for this solution but for updating from another identically-structured table (in my case website test DB to live DB):

INSERT  live-db.table1
SELECT  *
FROM    test-db.table1 t
ON DUPLICATE KEY UPDATE
        ColToUpdate1 = t.ColToUpdate1,
        ColToUpdate2 = t.ColToUpdate2,
        ...

As mentioned elsewhere, only the columns you want to update need to be included after ON DUPLICATE KEY UPDATE.

No need to list the columns in the INSERT or SELECT, though I agree it's probably better practice.

INSERT IGNORE INTO table (id, name, age) VALUES (1, "A", 19);

INTO TABLE (id, name, age) VALUES(1, "A", 19) ON DUPLICATE UPDATE SET NAME = "A", AGE = 19;

REPLACE INTO table (id, name, age) VALUES(1, "A", 19);

All these solution will work regarding your question.

If you want to know in details regarding these statement visit this link