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How do you effectively model inheritance in a database?

...etimes needed, when you want to load a list of all records (without doing select on each and every child table). One way to handle this, is to have one column representing the type of the child class (similar to the rowType field in the TPH), so mixing the TPT and TPH somehow. Say we want to des...
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Storyboard - refer to ViewController in AppDelegate

... If you use XCode 5 you should do it in a different way. Select your UIViewController in UIStoryboard Go to the Identity Inspector on the right top pane Check the Use Storyboard ID checkbox Write a unique id to the Storyboard ID field Then write your code. // Override point for ...
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What is the most ridiculous pessimization you've seen? [closed]

...nearly all their tables have an associated archive table, and most queries select from views that UNION the pairs of tables. Performance is as you would expect! – Tony Andrews Mar 26 '09 at 13:32 ...
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Running a cron every 30 seconds

... superb answer, should be the selected answer – GuidedHacking Feb 21 at 16:42 add a comment  |  ...
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Symbolicating iPhone App Crash Reports

...able if the script complains about it like so: export DEVELOPER_DIR=`xcode-select --print-path` . I added this line to my ~/.bash_profile. See stackoverflow.com/q/11682789/350761 – Eliot Sep 22 '13 at 6:54 ...
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CSS: bolding some text without changing its container's size

...e widths to be defined by the width of the menu item. I bold the currently-selected item. 11 Answers ...
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mongoDB/mongoose: unique if not null

... Just a quick update to those researching this topic. The selected answer will work, but you might want to consider using partial indexes instead. Changed in version 3.2: Starting in MongoDB 3.2, MongoDB provides the option to create partial indexes. Partial indexes offer a su...
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How to add an Access-Control-Allow-Origin header

...for the file scroll down to the file click the cog icon click Edit Headers select Access-Control-Allow-Origin add the single character '*' (without the quotes) hit enter repeat for the other files If you need to continue and do #2, then you'll need a command line with CURL curl -D - --header "X-A...
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Differences between Oracle JDK and OpenJDK

...mostly based on HotSpot source code donated by Sun. Moreover, OpenJDK was selected to be the reference implementation for Java 7 and is maintained by Oracle engineers. There's a more detailed answer from 2012 on difference between JVM, JDK, JRE & OpenJDK, which links to an Oracle blog post: ...
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Why do some functions have underscores “__” before and after the function name?

...ml", title = _("Title"), data = self.application.db.query("select ... where object_id=%s", self.object_id) ) ... share | improve this answer | follow ...