[英]MySql query in same column for different date
Please consider: I am talking about MySQL Database 请考虑:我在谈论MySQL数据库
I have two tables like this: 我有两个这样的表:
tbl_stock_info
+-----+--------+
| sId | sName |
+-----+--------+
| 1 | Apple |
| 2 | Google |
| 3 | Yahoo |
+-----+--------+
tbl_stock_data
+------------+----------+-------------+
| date | stock_id | stock_price |
+------------+----------+-------------+
| 2017-01-25 | 1 | 44.7 |
| 2017-01-25 | 3 | 51 |
| 2017-01-25 | 2 | 71.5 |
| 2017-01-24 | 1 | 44.9 |
| 2017-01-24 | 3 | 51.2 |
| 2017-01-24 | 2 | 71.3 |
+------------+----------+-------------+
The Output I am looking for is like this: 我正在寻找的输出是这样的:
+-----+--------+----------+----------+
| sId | sName | Price_25 | Price_24 |
+-----+--------+----------+----------+
| 1 | Apple | 44.7 | 44.9 |
| 2 | Google | 71.5 | 71.3 |
| 3 | Yahoo | 51 | 51.2 |
+-----+--------+----------+----------+
Any assistance would be greatly appreciated. 任何帮助将不胜感激。
You can do it with a query like this. 您可以使用这样的查询来做到这一点。 it search the newest 2 dates in the table and generate your query, but the column name are fix. 它会在表格中搜索最新的2个日期并生成您的查询,但列名是固定的。 if you want also to change them you must use a prepared statement. 如果您还想更改它们,则必须使用准备好的语句。
SELECT
si.*
,SUM(if(sd1.`date` = ( SELECT DISTINCT `date` FROM tbl_stock_data ORDER BY `date` DESC LIMIT 0,1), sd1.stock_price ,0) ) as lastday
,SUM(if(sd1.`date` = ( SELECT DISTINCT `date` FROM tbl_stock_data ORDER BY `date` DESC LIMIT 1,1), sd1.stock_price ,0) ) as daybefore
FROM tbl_stock_info si
LEFT JOIN tbl_stock_data sd1 ON sd1.stockid = si.sId
GROUP BY si.sId;
sample 样品
MariaDB [l]> SELECT * FROM tbl_stock_info;
+-----+--------+
| sId | sNAme |
+-----+--------+
| 1 | Apple |
| 2 | Google |
| 3 | Yahoo |
+-----+--------+
3 rows in set (0.00 sec)
MariaDB [l]> SELECT * FROM tbl_stock_data;
+----+------------+---------+-------------+
| id | date | stockid | stock_price |
+----+------------+---------+-------------+
| 1 | 2017-01-25 | 1 | 44.70 |
| 2 | 2017-01-25 | 3 | 51.00 |
| 3 | 2017-01-25 | 2 | 71.50 |
| 4 | 2017-01-24 | 1 | 44.90 |
| 5 | 2017-01-24 | 3 | 51.20 |
| 6 | 2017-01-24 | 2 | 71.30 |
| 7 | 2017-01-23 | 1 | 99.00 |
| 8 | 2017-01-22 | 2 | 22.00 |
| 9 | 2017-01-20 | 3 | 33.13 |
+----+------------+---------+-------------+
9 rows in set (0.01 sec)
test 测试
MariaDB [l]> SELECT
-> si.*
-> ,SUM(if(sd1.`date` = ( SELECT DISTINCT `date` FROM tbl_stock_data ORDER BY `date` DESC LIMIT 0,1), sd1.stock_price ,0) ) as lastday
-> ,SUM(if(sd1.`date` = ( SELECT DISTINCT `date` FROM tbl_stock_data ORDER BY `date` DESC LIMIT 1,1), sd1.stock_price ,0) ) as daybefore
-> FROM tbl_stock_info si
-> LEFT JOIN tbl_stock_data sd1 ON sd1.stockid = si.sId
-> GROUP BY si.sId;
+-----+--------+---------+-----------+
| sId | sNAme | lastday | daybefore |
+-----+--------+---------+-----------+
| 1 | Apple | 44.70 | 44.90 |
| 2 | Google | 71.50 | 71.30 |
| 3 | Yahoo | 51.00 | 51.20 |
+-----+--------+---------+-----------+
3 rows in set (0.00 sec)
MariaDB [l]>
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.