SQL 列不同的表查询结果合并操作

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两个不同的表进行查询，需要把结果合并，

比如table1的列为 id, user_id, type_id,pro_id；

table2的列为 id,user_id,collect_id；分别如下图所示

table1：

table2：

将两个表的查询结果合并到一起的查询语句为

select *, null as collect_id from table1 where user_id = 527
union
select id,user_id,null as type_id,null as pro_id, collect_id from table2 where user_id = 527;

结果为：

其实就是把对应的列补充到没有该列的表中，在例子中就是把collect_id补充到table1中,

把type_id,pro_id补充到table2中。

补充知识：sql结果集合并用union all 不同表的列合并用join

结果集合并用union all 不同表的列合并用join

SELECT
"模块名",
"事件编码",
"点击数量",
"使用时长（单位：分）"
FROM

(SELECT 
T.fun_name as "模块名",
T.event_code as "事件编码",
SUM(click_records) as "点击数量"
FROM 
(SELECT m.* FROM default.daily_new_clientrpt_master m WHERE event_id in ( SELECT max(event_id) AS "事件" from default.daily_new_clientrpt_master group by user_name,fun_code ORDER BY "事件" DESC ) ) T where day = today() GROUP BY "模块名" ,"事件编码") T5
JOIN
(
SELECT 
T.fun_name as "模块名",
T.event_code as "事件编码",
round(sum(stay_time)/60000,0) as "使用时长（单位：分）"
FROM 
(SELECT m.* FROM default.daily_new_clientrpt_master m WHERE event_id in 
 ( 
 SELECT "事件" FROM (
 SELECT max(event_id) AS "事件", max(stay_time) AS "事件1" from default.daily_new_clientrpt_master group by user_name,fun_code ORDER BY "事件1" DESC) )
) 
 T where day = today() AND like(event_code,'%10000') GROUP BY "模块名" ,"事件编码"
) T6 ON T5."模块名"=T6."模块名" AND T5."事件编码"=T6."事件编码"

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