Mybatis中insert和insertSelective区别

两者的区别在于如果选择insert 那么所有的字段都会添加一遍即使没有值
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    <insert id="insert" parameterType="com.ego.pojo.TbContentCategory" >insert into tb_content_category (id, parent_id, name,status, sort_order, is_parent,created, updated)values (#{id,jdbcType=BIGINT}, #{parentId,jdbcType=BIGINT}, #{name,jdbcType=VARCHAR},#{status,jdbcType=INTEGER}, #{sortOrder,jdbcType=INTEGER}, #{isParent,jdbcType=BIT},#{created,jdbcType=TIMESTAMP}, #{updated,jdbcType=TIMESTAMP})</insert>

     

inserSelective就会只给有值的字段赋值
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    <insert id="insertSelective" parameterType="com.ego.pojo.TbContentCategory" >insert into tb_content_category<trim prefix="(" suffix=")" suffixOverrides="," ><if test="id != null" >id,</if><if test="parentId != null" >parent_id,</if><if test="name != null" >name,</if><if test="status != null" >status,</if><if test="sortOrder != null" >sort_order,</if><if test="isParent != null" >is_parent,</if><if test="created != null" >created,</if><if test="updated != null" >updated,</if></trim><trim prefix="values (" suffix=")" suffixOverrides="," ><if test="id != null" >#{id,jdbcType=BIGINT},</if><if test="parentId != null" >#{parentId,jdbcType=BIGINT},</if><if test="name != null" >#{name,jdbcType=VARCHAR},</if><if test="status != null" >#{status,jdbcType=INTEGER},</if><if test="sortOrder != null" >#{sortOrder,jdbcType=INTEGER},</if><if test="isParent != null" >#{isParent,jdbcType=BIT},</if><if test="created != null" >#{created,jdbcType=TIMESTAMP},</if><if test="updated != null" >#{updated,jdbcType=TIMESTAMP},</if></trim></insert>

     

用一个例子说明一下
  1. 前提Goods商品表里面有三个字段:id,name,price

  2. 1.此时我只设置了一个字段名字:

  3. Goods g = new Goods();

  4. g.setName("手机");

  5. insertSelective(g);

  6. insertSelective执行对应的sql语句的时候,只插入对应的name字段;

  7. (主键是自动添加的,默认插入为空)insert into tb_goods (id,name) value (null,"手机");

  8. 注意:此时是没有price什么事的

  9. 2、如果使用insert则是不论你设置多少个字段,统一都要添加一遍,不论你设置几个字段,即使是一个。

  10. Goods g=new Goods();

  11. g.setName("冰箱");

  12. insert(g)

  13. insert执行对应的sql语句的时候,统一都要添加一遍;

  14. insert into tb_goods (id,name,price) value (null,"冰箱",null);

  15. 注意:price也在哦!!

转自:https://blog.csdn.net/hello_word2/article/details/80560725