要查詢的sql:

select * from user where name = ? and (age=? or city=?)；

方法1：不使用Example查詢

直接在usermapper.xml中修改sql

方法2：使用Example查詢

sql可轉換成

select * from user where (name = ? and age=?) or (name=? and city=?)；

然後使用Example查詢

UserExample example=new UserExample();
example.or().orAgeLike("%"+searchParam+"%").andNameEqualTo(userName);
example.or().orCityLike("%"+searchParam+"%").andNameEqualTo(userName);

補充知識：MySQL/Mybatis多個AND和OR混用注意事項

mysql中AND的優先順序高於OR，所以在查詢時，會優先執行AND條件，除非使用（）來將一個AND和OR括起來，這樣才能使得OR得以按照語句的順序執行。

如下圖所示：

java測試程式碼

@Test
 public void TestMutil(){
  Species species = new Species();
  ArrayList<String> arrayList = new ArrayList<String>();
  arrayList.add("長喙蚤");
  arrayList.add("尤氏");
  List<Species> querySpeciesesListByMutilCondition = this.speciesMapper.querySpeciesesListByMutilCondition(arrayList,species.getEnglishName(),species.getHost(),species.getPosition(),species.getLocation(),species.getPhylum(),species.getClassName(),species.getOrder(),species.getFamily(),species.getJenus());
  
  for (Species s : querySpeciesesListByMutilCondition) {
   System.out.println(s);
  }
  System.out.println(querySpeciesesListByMutilCondition.size());
  
 }

Mapper檔案中沒有使用（）放在語句中執行情況

<select id="querySpeciesesListByMutilCondition" resultType="Species">
 SELECT * FROM t_json_species
 <where>
 <if test="englisName != null and englisName != ''">AND englishName like CONCAT('%',#{englishName},'%') OR sameName like CONCAT('%','%')</if>
 <if test="host != null and host != ''">AND host like CONCAT('%',#{host},'%')</if>
 <if test="position != null and position != ''">AND position like CONCAT('%',#{position},'%')</if>
 <if test="location != null and location != ''">AND location like CONCAT('%',#{location},'%')</if>
 <if test="phylumName != null and phylumName != ''">AND phylumName = #{phylumName}</if>
 <if test="className != null and className != ''">AND className = #{className}</if>
 <if test="orderName != null and orderName != ''">AND orderName = #{orderName}</if>
 <if test="familyName != null and familyName != ''">AND familyName = #{familyName}</if>
 <if test="jenusName != null and jenusName != ''">AND jenusName = #{jenusName}</if>
 <if test="nameList != null and nameList != ''">
 <foreach collection="nameList" item="name" >AND name like CONCAT('%',#{name},'%')</foreach>
 </if>
 </where>
 
 </select>

Mapper檔案中使用（）放在語句中執行情況

<select id="querySpeciesesListByMutilCondition" resultType="Species">
 SELECT * FROM t_json_species
 <where>
 <if test="englisName != null and englisName != ''">AND englishName like CONCAT('%','%')</if>
 <if test="phylumName != null and phylumName != ''">AND phylumName = #{phylumName}</if>
 <if test="className != null and className != ''">AND className = #{className}</if>
 <if test="orderName != null and orderName != ''">AND orderName = #{orderName}</if>
 <if test="familyName != null and familyName != ''">AND familyName = #{familyName}</if>
 <if test="jenusName != null and jenusName != ''">AND jenusName = #{jenusName}</if>
 <if test="nameList != null and nameList != ''">
 <foreach collection="nameList" item="name" >AND (name like CONCAT('%','%'))</foreach>
 </if>
 </where>
 
 </select>

補充：

如果這裡使用多個%來解決上述的含有多個OR和AND情況，那麼所實現功能會有問題，因為多個關鍵詞有%來連線，會有一個次序問題。具體效果見下圖

以上這篇mybatis and,or複合查詢操作就是小編分享給大家的全部內容了，希望能給大家一個參考，也希望大家多多支援我們。