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How to update column with null value

...ed Oct 6 '10 at 8:11 Daniel VassalloDaniel Vassallo 301k6666 gold badges475475 silver badges424424 bronze badges ...
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How do you easily horizontally center a using CSS? [duplicate]

I'm trying to horizontally center a <div> block element on a page and have it set to a minimum width. What is the simplest way to do this? I want the <div> element to be inline with rest of my page. I'll try to draw an example: ...
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Why does Python pep-8 strongly recommend spaces over tabs for indentation?

...andard library in the main Python distribution. The intention is to make all code that goes in the official python distribution consistently formatted (I hope we can agree that this is universally a Good Thing™). Since the decision between spaces and tabs for an individual programmer is a) real...
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How to make a SIMPLE C++ Makefile

...o write a simple makefile What is Make? And Why Should I Care? The tool called Make is a build dependency manager. That is, it takes care of knowing what commands need to be executed in what order to take your software project from a collection of source files, object files, libraries, headers, et...
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Why are there two build.gradle files in an Android Studio project?

...a "Top-level build file" where you can add configuration options common to all sub-projects/modules. If you use another module in your project, as a local library you would have another build.gradle file: <PROJECT_ROOT>\module\build.gradle For example in your top level file you can specify t...
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MySQL: multiple tables or one table with many columns?

...elational database to minimize redundancy and dependency. Normalization usually involves dividing large tables into smaller (and less redundant) tables and defining relationships between them. The objective is to isolate data so that additions, deletions, and modifications of a field can be made in ...
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Best way to remove from NSMutableArray while iterating?

.... That may be true (although what about the memory and processing cost of allocating a new array, and discarding the old one?) but even if it's faster it may not be as big a deal as it would be for a naive implementation, because NSArrays do not behave like "normal" arrays. They talk the talk but ...
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I just discovered why all ASP.Net websites are slow, and I am trying to work out what to do about it

...ach other. However, a read-write-session page can't start processing until all read-only requests have completed, and while it is running it must have exclusive access to that user's session in order to maintain consistency. Locking on individual values wouldn't work, because what if one page change...
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How does one escape backslashes and forward slashes in VIM find/search?

...erent delimiter instead: :%s@<doc/>@<cat\\>@ This saves you all typing all those time-consuming, confusing backslashes in patterns with a ton of slashes. From the documentation: Instead of the / which surrounds the pattern and replacement string, you can use any other single-b...
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Convert timedelta to total seconds

...ime.datetime.fromtimestamp(time.mktime(time.gmtime())) expression. (1) If all you need is the difference between two instants in seconds, the very simple time.time() does the job. (2) If you are using those timestamps for other purposes, you need to consider what you are doing, because the result ...