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Insert auto increment primary key to existing table
...ering if it's possible to insert data into the primary key column automatically (I already have 500 rows in DB and want to give them id but I don't want to do it manually). Any thoughts? Thanks a lot.
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select and update database record with a single queryset
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@learning well dude, it all depends on your scenario. The update method is great for mass updates, but it should set off a warning in your head when you use it that you need to review any signals attached to that object that might also need to be m...
Python circular importing?
... of it) for the first time, the code inside the module is executed sequentially like any other code; e.g., it is not treated any differently that the body of a function. An import is just a command like any other (assignment, a function call, def, class). Assuming your imports occur at the top of th...
CDN（内容分发网络）技术原理 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...功能，所以大部分网页对象（Web page object），如html, htm, php等页面文件，gif,tif, png, bmp等图片文件，以及其他格式的文件，在有效期（TTL）内，对于重复的访问，不必从原始网站重新传送文件实体，只需通过简单的认证（Freshness V...
What does the “__block” keyword mean?
What exactly does the __block keyword in Objective-C mean? I know it allows you to modify variables within blocks, but I'd like to know...
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How to determine SSL cert expiration date from a PEM encoded certificate?
...an I query the cert file for when it will expire? Not a web site, but actually the certificate file itself, assuming I have the csr, key, pem and chain files.
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PostgreSQL Crosstab Query
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Install the additional module tablefunc once per database, which provides the function crosstab(). Since Postgres 9.1 you can use CREATE EXTENSION for that:
CREATE EXTENSION IF NOT EXISTS tablefunc;
Improved test case
CREATE ...
How do I list loaded plugins in Vim?
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Not a VIM user myself, so forgive me if this is totally offbase. But according to what I gather from the following VIM Tips site:
" where was an option set
:scriptnames : list all plugins, _vimrcs loaded (super)
:verbose set history? : reveals value of hist...
How do I reference an existing branch from an issue in GitHub?
...ant to do this, I manually make the link like this:
[a link to a branch](/_user_/_project_/tree/_branch_)
Where _user_, _project_, and _branch_ should be replaced with the parts of the branch's URL. For example, a branch in GitHub's "linguist" project:
[api-changes branch in github/linguist](/g...
What is the printf format specifier for bool?
...sing a single char * to printf() is considered bad practice because it's really supposed to be a format string, and an unescaped percent sign might cause your program to blow up (see here for more). Thus, printf("%s", ...) is safer. If you're not doing any actual formatting to begin with, the printf...