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How to delete a record in Django models?
...at is the case after DJango 1.4, but this is actually fetching all the PKs and then delete by those PKs. So eg if you delete by an arbitrary field, this can be way slower then the SQL counterpart... :(
– Vajk Hermecz
Mar 25 '14 at 16:22
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What's the difference between a catalog and a schema in a relational database?
... other things--all of the various schemas (external, conceptual, internal) and all of the corresponding mappings (external/conceptual, conceptual/internal) are kept.
In other words, the catalog contains detailed information (sometimes called descriptor information or metadata) regarding the va...
How to specify the order of CSS classes?
I'm a little confused about CSS and the class attribute. I always thought, the order in which I specify multiple classes in the attribute value has a meaning. The later class could/should overwrite definitions of the previous, but this doesn't seem to work. Here's an example:
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offsetting an html anchor to adjust for fixed header [duplicate]
...r than where it actually appears on the page, by making it a block element and relatively positioning it. -250px will position the anchor up 250px
a.anchor {
display: block;
position: relative;
top: -250px;
visibility: hidden;
}
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class name and method name dropdown list is missing (visual studio setting)
Does anyone know how to get my class name and method name dropdown lists again? It's the dropdown lists that are usually above the code. It's just a setting but i can't seem to find it. I don't want to reset my setting btw. I shouldn't have to.
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Getting pids from ps -ef |grep keyword
...u include the -f options. That makes pgrep match keywords in the whole command (including arguments) instead of just the process name.
pgrep -f keyword
From the man page:
-f The pattern is normally only matched against the process name. When -f is set, the full command line is used....
PHP prepend associative array with literal keys?
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See also array_merge() and its difference from using the + operator: br.php.net/manual/en/function.array-merge.php#92602
– Havenard
Sep 3 '09 at 1:33
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驯服Linux OOM Killer（优质英文资料翻译） - 操作系统(内核) - 清泛网移动...
驯服Linux OOM Killer（优质英文资料翻译）Taming-the-OOM-killer全面介绍Linux OOM Killer的内部原理，原文为英文，Google翻译+校对，若翻译不佳请参考原文，谢谢。在极低的内存条件下， OOM（out-of-memory） Killer会启动并使用一组随时间演变...
In Unix, can I run 'make' in a directory without cd'ing to that directory first?
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Grump - that isn't in standard make; it must be a GNU extension. Since you say Linux and Unix, it isn't clear which you want, but the -C option won't work on Solaris 10 (/usr/ccs/bin/make), AIX (/usr/bin/make), or HP-UX 11.23 (/usr/bin/make). Stil...
How to Deal with Temporary NSManagedObject instances?
I need to create NSManagedObject instances, do some stuff with them and then trash them or store to sqlite db. The problem is, I cannot create instances of NSManagedObject unconnected to NSManagedObjectContext and this means I have to clear up somehow after I decide that I don't need some of ...