mysql Column count doesn't match value count at row 1

今天执行批量插入的操作，发现报了错 mysql Column count doesn't match value count at row 1。

后来发现原因：是由于写的SQL语句里列的数目和后面的值的数目不一致， 比如insert into 表名 (field1,field2,field3) values('a','b')这样前面的是三列，后面却只有二个值，这就会出现这个错误的。 

查看mapper写法

<insert id="insertBatch" useGeneratedKeys="true" parameterType="java.util.List">
 INSERT INTO sys_basic_info(  3     <include refid="dbColumns" />
 ) VALUES  5     <foreach collection="list" item="item" index="index" open="(" separator="," close=")">
 #{item.groupId},  7  #{item.groupName},  8  #{item.groupCode}  9     </foreach>
</insert>

原因很容易发现，foreach标签属性open和close配置有误！这样大括号会把整体包起来，正确应为：

<insert id="insertBatch" useGeneratedKeys="true" parameterType="java.util.List">
 INSERT INTO sys_basic_info(  3     <include refid="dbColumns" />
 ) VALUES  5     <foreach collection="list" item="item" index="index" separator=",">
 (  7  #{item.groupId},  8  #{item.groupName},  9  #{item.groupCode} 10  ) 11     </foreach>
</insert>