大约有 47,000 项符合查询结果(耗时:0.0223秒) [XML]

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Find rows that have the same value on a column in MySQL

...sses and how many times they're used, with the most used addresses first. SELECT email, count(*) AS c FROM TABLE GROUP BY email HAVING c > 1 ORDER BY c DESC If you want the full rows: select * from table where email in ( select email from table group by email having count(*) &g...
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How to export query result to csv in Oracle SQL Developer?

...worksheet toolbar) That's it. Method 2 Run a query Right click and select unload. Update. In Sql Developer Version 3.0.04 unload has been changed to export Thanks to Janis Peisenieks for pointing this out Revised screen shot for SQL Developer Version 3.0.04 From the format drop down...
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Selecting only numeric columns from a data frame

...traightforward, and robust to use on database-back-ended tibbles: dplyr::select_if(x, is.numeric) share | improve this answer | follow | ...
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How do I convert an interval into a number of hours with postgres?

... Probably the easiest way is: SELECT EXTRACT(epoch FROM my_interval)/3600 share | improve this answer | follow | ...
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MySQL IF NOT NULL, then display 1, else display 0

... SELECT c.name, IF(a.addressid IS NULL,0,1) AS addressexists FROM customers c LEFT JOIN addresses a ON c.customerid = a.customerid WHERE customerid = 123 ...
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Max or Default?

...d, you can get around this limitation by casting to a nullable within your select. My VB is a little rusty, but I think it'd go something like this: Dim x = (From y In context.MyTable _ Where y.MyField = value _ Select CType(y.MyCounter, Integer?)).Max Or in C#: var x = (from y...
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MySQL: How to copy rows, but change a few fields?

...able ( Event_ID , col2 ... ) SELECT "155" , col2 ... FROM Table WHERE Event_ID = "120" Here, the col2, ... represent the remaining columns (the ones other than Event_ID) in your table. ...
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Convert timestamp to date in MySQL query

... SELECT * FROM users WHERE DATE_FORMAT(FROM_UNIXTIME(users.user_created_at),'%Y-%b-%e') = '2015-03-06' is this correct format or should i modify this? – Dheeraj Thedijje Mar 7 '18 at 11:4...
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XPath - Selecting elements that equal a value

In Xpath, I am wanting to select elements that equal a specific value. 2 Answers 2 ...
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How to get the number of days of difference between two dates on mysql?

...lues are used in the calculation In your case, you'd use : mysql> select datediff('2010-04-15', '2010-04-12'); +--------------------------------------+ | datediff('2010-04-15', '2010-04-12') | +--------------------------------------+ | 3 | +--------------...