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How to get multiple counts with one SQL query?
... entire nested query with a simple count(*) as @Mihai shows - with further MySQL only syntax simplifications.
– YoYo
Apr 1 '17 at 19:29
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T-SQL: Opposite to string concatenation - how to split string into multiple records [duplicate]
... Pieces(pn, start, stop) AS (
SELECT 1, 1, CHARINDEX(@sep, @s)
UNION ALL
SELECT pn + 1, stop + 1, CHARINDEX(@sep, @s, stop + 1)
FROM Pieces
WHERE stop > 0
)
SELECT pn,
SUBSTRING(@s, start, CASE WHEN stop > 0 THEN stop-start ELSE 512 END) AS s
FRO...
手把手教你如何加入主流DSP广告联盟 - 更多技术 - 清泛网 - 专注C/C++及内核技术
手把手教你如何加入主流DSP广告联盟打造好自己的网站后，考虑后续的持续运营，可能需要引入互联网广告。前期由于网站知名度不高，最好挂一些联盟广告，它会根据用户的浏览记录自动推荐相应广告内容，对于站长来说也比...
Windows重置网络命令 - 更多技术 - 清泛网 - 专注C/C++及内核技术
Windows重置网络命令启动cmd.exe命令提示窗口，输入以下命令：命令：netsh winsock reset回车，重启电脑，即可重置网络连接配置。在一般的网络连接问题中，这...启动cmd.exe命令提示窗口，输入以下命令：
命令：netsh winsock reset
...
1052: Column 'id' in field list is ambiguous
...ection
FROM tbl_names
NATURAL JOIN tbl_section
See also: https://dev.mysql.com/doc/refman/5.7/en/join.html
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How do I get SUM function in MySQL to return '0' if no values are found?
Say I have a simple function in MySQL:
4 Answers
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'IF' in 'SELECT' statement - choose output value based on column values
...IF(type = 'P', amount, amount * -1) as amount
FROM report
See http://dev.mysql.com/doc/refman/5.0/en/control-flow-functions.html.
Additionally, you could handle when the condition is null. In the case of a null amount:
SELECT id,
IF(type = 'P', IFNULL(amount,0), IFNULL(amount,0) * -1) as...
How can you represent inheritance in a database?
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Does other DBs support INHERITS besides PostgreSQL ? MySQL for example ?
– giannis christofakis
Mar 11 '16 at 9:00
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Get top n records for each group of grouped results
...g this: The version is the variables is close to being correct. However, MySQL does not guarantee the order of evaluation of expressions in the SELECT (and, in fact, sometimes evaluates them out-of-order). The key to the solution is to put all the variable assignments in a single expression; here...
App Inventor 2 开发多用户注册登录签到系统 - AppInventor连接网络微数据...
...程
“网络微数据库”如何保存值到网络，如何读取网络值
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如何存储用户的每日签到列表数据（用户的子对象存储）
aia源码
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