-------------------------动态查询---------------------------------------
<select id="findAll" parameterType="map" resultMap="studentMap"> select * from students <where> <if test="pid!=null"> and students_id = #{pid} </if> <if test="pname!=null"> and students_name = #{pname} </if> <if test="psal!=null"> and students_sal = #{psal} </if> </where> </select>
public List<Student> findAll(Integer id,String name,Double sal) throws Exception{
SqlSession sqlSession = null; try{ sqlSession = MybatisUtil.getSqlSession(); Map<String,Object> map = new LinkedHashMap<String,Object>(); map.put("pid",id); map.put("pname",name); map.put("psal",sal); return sqlSession.selectList("studentNamespace.findAll",map); }catch(Exception e){ e.printStackTrace(); throw e; }finally{ MybatisUtil.closeSqlSession(); } } -----------------------------------动态更新----------------------------------------- <update id="dynaUpdate" parameterType="map"> update students <set> <if test="pname!=null"> students_name = #{pname}, </if> <if test="psal!=null"> students_sal = #{psal}, </if> </set> where students_id = #{pid} </update>
public void dynaUpdate(Integer id,String name,Double sal) throws Exception{
SqlSession sqlSession = null; try{ sqlSession = MybatisUtil.getSqlSession(); Map<String,Object> map = new HashMap<String, Object>(); map.put("pid",id); map.put("pname",name); map.put("psal",sal); sqlSession.update("studentNamespace.dynaUpdate",map); sqlSession.commit(); }catch(Exception e){ e.printStackTrace(); sqlSession.rollback(); throw e; }finally{ MybatisUtil.closeSqlSession(); } } -----------------------------------动态删除---------------------------------------------- <delete id="dynaDeleteArray"> delete from students where students_id in <!-- foreach用于迭代数组元素 open表示开始符号 close表示结束符合 separator表示元素间的分隔符 item表示迭代的数组，属性值可以任意，但提倡与方法的数组名相同 #{ids}表示数组中的每个元素值 --> <foreach collection="array" open="(" close=")" separator="," item="ids"> #{ids} </foreach> </delete>/** * 根据ID批量删除学生(数组版本) */ public void dynaDeleteArray(int... ids) throws Exception{ SqlSession sqlSession = null; try{ sqlSession = MybatisUtil.getSqlSession(); sqlSession.delete("studentNamespace.dynaDeleteArray",ids); sqlSession.commit(); }catch(Exception e){ e.printStackTrace(); sqlSession.rollback(); throw e; }finally{ MybatisUtil.closeSqlSession(); } } /** * 根据ID批量删除学生(集合版本) */ public void dynaDeleteList(List<Integer> ids) throws Exception{ SqlSession sqlSession = null; try{ sqlSession = MybatisUtil.getSqlSession(); sqlSession.delete("studentNamespace.dynaDeleteList",ids); sqlSession.commit(); }catch(Exception e){ e.printStackTrace(); sqlSession.rollback(); throw e; }finally{ MybatisUtil.closeSqlSession(); } } ------------------------------------动态插入---------------------------------------------- <!-- sql片段对应字段名,id属性值任意 --> <sql id="key"> <!-- 去掉最后一个, --> <trim suffixOverrides=","> <if test="id!=null"> students_id, </if> <if test="name!=null"> students_name, </if> <if test="sal!=null"> students_sal, </if> </trim> </sql> <!-- sql片段对应?,id属性值任意 --> <sql id="value"> <!-- 去掉最后一个, --> <trim suffixOverrides=","> <if test="id!=null"> #{id}, </if> <if test="name!=null"> #{name}, </if> <if test="sal!=null"> #{sal}, </if> </trim> </sql> <!-- <include refid="key"/>和<include refid="value"/>表示引用上面定义的sql片段 --> <insert id="dynaInsert" parameterType="cn.itcast.javaee.mybatis.app14.Student"> insert into students(<include refid="key"/>) values(<include refid="value"/>) </insert>
public void dynaInsert(Student student) throws Exception{
SqlSession sqlSession = null; try{ sqlSession = MybatisUtil.getSqlSession(); sqlSession.insert("studentNamespace.dynaInsert",student); sqlSession.commit(); }catch(Exception e){ e.printStackTrace(); sqlSession.rollback(); throw e; }finally{ MybatisUtil.closeSqlSession(); } }