Mybatis支援多個條件的查詢，使用if標籤拼接。

下面是三個條件的查詢得例子，使用的資料庫是mysql，用到了模糊查詢及in做條件查詢。

xml檔案：

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
  PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
  "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="">
	<select id="selectTeacher" parameterType="map" resultType="map">
		select t.tid,t.tname,t.taddr
		from test_teacher t
		where 1=1
		<if test="tid != '' and tid != null">
			and tid=#{tid}
		</if>
		<if test="tname != '' and tname != null">
			and tname like #{tname}
		</if>
		<if test="addrs != '' and addrs != null">
			and taddr in
			<foreach item="item" index="index" collection="addrs" open="("
				separator="," close=")">
				#{item}
			</foreach>
		</if>

	</select>


</mapper>
 

dao層：

package mybatis.dao;

import java.util.List;

public interface TestTeacherDao {
	public List selectTeacher(String tid,String tname,List addrs);
}

package mybatis.dao;

import java.io.InputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

public class TestTeacherDaoImpl implements TestTeacherDao {
	private int res=-1;
	private SqlSession sqlSession=null;
	public  SqlSession getSqlSession(){
		
		try{
			String resource="mybatis-config.xml";
			InputStream is=org.apache.ibatis.io.Resources.getResourceAsStream(resource);
			SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(is);
			sqlSession=sqlSessionFactory.openSession(true);
			
			
		}catch(Exception e){
			System.out.println("出錯");
			e.printStackTrace();
		}
		return sqlSession;
	}
	@Override
	public List selectTeacher(String tid,String tname,List addrs) {
		Map map=new HashMap();
		map.put("tid", tid);
		map.put("tname", "%"+tname+"%");
		map.put("addrs",addrs);

		sqlSession=getSqlSession();
		List list=sqlSession.selectList("selectTeacher", map);
		return list;
	}

}
 

package mybatis.test;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import mybatis.dao.TestTeacherDao;
import mybatis.dao.TestTeacherDaoImpl;

public class Test {

	public static void main(String[] args) {
		TestTeacherDao td=new TestTeacherDaoImpl();
		List addrs=new ArrayList();
		addrs.add("shandong");
		addrs.add("beijing");
		List list=td.selectTeacher("", "",addrs);
		for(int i=0;i<list.size();i++){
			Map map=(Map)(list.get(i));					
			System.out.println(map.get("tname"));
		}
	}

}