Mybatis的foreach批量插入数据

案例一、

<if test="checkRepeat">
   <foreach collection="demoBodyList" item="demoBody" separator=";">
      INSERT INTO demo
      (a,b,c,d,e,f)
      SELECT
      #{demoBody.a,jdbcType=INTEGER},
      #{demoBody.b,jdbcType=INTEGER},
      #{demoBody.c,jdbcType=INTEGER},
      #{demoBody.d,jdbcType=INTEGER},
      #{demoBody.e,jdbcType=INTEGER},
      #{demoBody.f,jdbcType=INTEGER}
      FROM dual WHERE NOT EXISTS (
      SELECT a,b,c,d,e,f FROM demo
      WHERE
      a=#{demoBody.a,jdbcType=INTEGER}
      AND b=#{demoBody.b,jdbcType=INTEGER}
      AND c=#{demoBody.c,jdbcType=INTEGER}
      AND d=#{demoBody.d,jdbcType=INTEGER}
      AND e=#{demoBody.e,jdbcType=INTEGER}
      )
   </foreach>
</if>
<if test="!checkRepeat">
   INSERT INTO demo
   (a,b,c,d,e,f)
   VALUES
   <foreach collection="demoBodyList" item="demoBody" separator=",">
      (
      #{demoBody.a,jdbcType=INTEGER},
      #{demoBody.b,jdbcType=INTEGER},
      #{demoBody.c,jdbcType=INTEGER},
      #{demoBody.d,jdbcType=INTEGER},
      #{demoBody.e,jdbcType=INTEGER},
      #{demoBody.f,jdbcType=INTEGER}
      )
   </foreach>
</if>

若checkRepeat为true，那么会根据字段[a,b,c,d,e]批量插入或更新，反之直接批量插入

案例二、批量插入并更新

<foreach collection="demoBodyList" item="demoBody" separator=";">
   INSERT INTO demo
   (unique_a,b,c,d,e,f,g,h,i,j)
   VALUES
   (
   #{demoBody.a,jdbcType=INTEGER},
   #{demoBody.b,jdbcType=INTEGER},
   #{demoBody.c,jdbcType=INTEGER},
   #{demoBody.d,jdbcType=INTEGER},
   #{demoBody.e,jdbcType=INTEGER},
   #{demoBody.f,jdbcType=INTEGER},
   #{demoBody.g,jdbcType=INTEGER},
   #{demoBody.h,jdbcType=INTEGER},
   #{demoBody.i,jdbcType=INTEGER},
   #{demoBody.j,jdbcType=INTEGER}
   )
   ON DUPLICATE KEY UPDATE
   b=VALUES(b),
   c=VALUES(c),
   d=VALUES(d),
   e=VALUES(e),
   f=VALUES(f),
   g=VALUES(g),
   h=VALUES(h),
   i=VALUES(i),
   j=VALUES(j)
</foreach>

批量插入并更新，前提将a字段设置为唯一键，若插入的a字段已存在，那么更新ON DUPLICATE KEY UPDATE下的字段