mysql 插入前查重_插入新数据是直接查重，如果有重复则不插入数据

mabatis的XML文件写法

INSERT INTO t_cluster_server (id,cluster_id,server_id)

SELECT

#{id},

#{clusterId},

#{serverId}

FROM

DUAL

WHERE NOT EXISTS (

SELECT

*

FROM

t_cluster_server

WHERE

t_cluster_server.cluster_id = #{clusterId} and

t_cluster_server.server_id = #{serverId}

);

sql语句：

INSERT INTO t_cluster_server (

id,

cluster_id,

server_id

) SELECT

10345,

'IBM',

'advertising'

FROM

DUAL

WHERE

NOT EXISTS (

SELECT

*

FROM

t_cluster_server

WHERE

t_cluster_server.cluster_id = 'IBM' and

t_cluster_server.server_id = 'advertising'

);