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2021
09-29

mybatis返回类型map时如何将key大写转为小写

亲测:

SELECT DEPTNO as "deptno",DEPTNAME,DEPTGRADE,PARENTDEPT 
      FROM VMGR_DEPT
      ORDER BY DEPTGRADE,DEPTNO

别人案例:

  <select id="selectBlogRetHashMap" parameterType="int" resultType="map">  
        SELECT id AS "id", title AS "title", content AS "content" FROM Blog WHERE id = #{id}  
    </select> 

纯java实现方法(推荐):

public class Snippet {
	public static Map<String, Object> transformUpperCase(Map<String, Object> orgMap) {
		Map<String, Object> resultMap = new HashMap<>();
 
		if (orgMap == null || orgMap.isEmpty()) {
			return resultMap;
		}
 
		Set<String> keySet = orgMap.keySet();
		for (String key : keySet) {
			String newKey = key.toLowerCase();
			newKey = newKey.replace("_", "");
 
			resultMap.put(newKey, orgMap.get(key));
		}
 
		return resultMap;
	}
}

mybatis映射map返回的全是大写

解决方法

在查询的字段后加别名

user_id as “userId”

注意:别名必须加双引号

<select id="queryMaxPriceAAndUser" parameterType="java.lang.String" resultType="java.util.HashMap">
    SELECT A.SELL_PRICE as "price", B.USER_ID as "userId"
      FROM QLYY_SELL_AUCTION_RECORD A, QLYY_SELL_APPLY B
     WHERE A.SELL_PRICE = (SELECT MAX(SELL_PRICE)
                             FROM QLYY_SELL_AUCTION_RECORD
                            WHERE SELL_PROGRAM_ID = #{programId})
       AND A.SELL_PROGRAM_ID = #{programId}
       AND B.APPLY_CODE = A.SELL_USER
  </select>

以上为个人经验,希望能给大家一个参考,也希望大家多多支持自学编程网。

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