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Altering a column to be nullable

... If this was MySQL syntax, the type would have been missing, as some other responses point out. Correct MySQL syntax would have been: ALTER TABLE Merchant_Pending_Functions MODIFY NumberOfLocations INT NULL Posting here for clarity to ...
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Can I change a column from NOT NULL to NULL without dropping it?

... I tried with alter column and it didn't work with the latest mysql server. I tried with modify column and it worked. Strange... – Kostas Andrianos Aug 19 '17 at 15:29 ...
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常用Sql - 爬虫/数据库 - 清泛IT社区,为创新赋能!

本帖最后由 zqp2013 于 2015-3-17 22:06 编辑 mysql:drop table if exists tablename; 不能写成 drop table tablename if exists tablename; mysql:建立索引Sql CREATE TABLE tablename (   `ID`                 &nbs...
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How to get a one-dimensional scalar array as a doctrine dql query result?

...as callback, instead of writing a closure. $result = $em->createQuery("SELECT a.id FROM Auction a")->getScalarResult(); $ids = array_map('current', $result); See Petr Sobotka's answer below for additional info regarding memory usage. PHP >= 5.5 As jcbwlkr's answered below, the rec...
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What are the basic rules and idioms for operator overloading?

...t version. For the -> operator, if value_type is of class (or struct or union) type, another operator->() is called recursively, until an operator->() returns a value of non-class type. The unary address-of operator should never be overloaded. For operator->*() see this question. It's ...
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“No backupset selected to be restored” SQL Server 2012

...n I try with the UI approach ("Restore"), I get message @ top No backupset selected to be restored. – The Red Pea Apr 27 '17 at 16:50 ...
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你不得不知道的6个用好大数据的秘诀 - 资讯 - 清泛网 - 专注C/C++及内核技术

...也不能代表它就一定会获得商业上的成功。只有真正懂得如何利用大数据,了解到公司利用大数据可以达到什么目标,公司最终才有可能真正成功。在公司在发展过程中往往也会面临诸多选择,也只有目标设定明确了,才能够缩...
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How do you move a file?

...files, right-dragged, the regular windows explorer menu came up. It let me select "move" but it wasn't an SVN option so I'm not sure anything even happened. When I checked to see if there were modifications, it said 300 files were deleted and 300 were non-versioned. This doesn't seem like it worked ...
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Tools for Generating Mock Data? [closed]

... If you are looking or willing to use something MySQL-specific, you could take a look at Super Smack. It is currently maintained by Tony Bourke. Super Smack allows you to generate random data to insert into your database tables. It is customizable, allowing you to use...
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How To Get IPython Notebook To Run Python 3?

...led "root". In order to launch application using another environment, just select the desired environment from the list, to make it active. share | improve this answer | foll...