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Xcode stops working after set “xcode-select -switch”

...eloper directory, not the Xcode application bundle. Run this: sudo xcode-select --switch /Applications/Xcode.app/Contents/Developer With recent versions of Xcode, you can go to Xcode ➙ Preferences… ➙ Locations and pick one of the options for Command Line Tools to set the location. ...
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What is the PostgreSQL equivalent for ISNULL()

... SELECT CASE WHEN field IS NULL THEN 'Empty' ELSE field END AS field_alias Or more idiomatic: SELECT coalesce(field, 'Empty') AS field_alias share...
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Join/Where with LINQ and Lambda

...tabase.Post_Metas on post.ID equals meta.Post_ID where post.ID == id select new { Post = post, Meta = meta }; If you're really stuck on using lambdas though, your syntax is quite a bit off. Here's the same query, using the LINQ extension methods: var id = 1; var query = database.Posts //...
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Xcode + remove all breakpoints

...l breakpoints. In Xcode4 press CMD(⌘)+6, in Xcode3 press CMD(⌘)+ALT+B. Select all breakpoints with CMD(⌘)+A and delete them, like deleting text, with backspace. There's no step 3 :) share | i...
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How to fix .pch file missing on build?

...the bottom of the drop-down menu. At the top left of the Properties Pages, select All Configurations from the drop-down menu. Open the C/C++ tree and select Precompiled Headers Precompiled Header: Select Use (/Yu) Fill in the Precompiled Header File field. Standard is stdafx.h Click Okay If you do n...
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How do you list the primary key of a SQL Server table?

... SELECT Col.Column_Name from INFORMATION_SCHEMA.TABLE_CONSTRAINTS Tab, INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE Col WHERE Col.Constraint_Name = Tab.Constraint_Name AND Col.Table_Name = Tab.Table_Name ...
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How do I check if an index exists on a table field in MySQL?

... Try: SELECT * FROM information_schema.statistics WHERE table_schema = [DATABASE NAME] AND table_name = [TABLE NAME] AND column_name = [COLUMN NAME] It will tell you if there is an index of any kind on a certain column wi...
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Convert Unix timestamp into human readable date using MySQL

... Use FROM_UNIXTIME(): SELECT FROM_UNIXTIME(timestamp) FROM your_table; See also: MySQL documentation on FROM_UNIXTIME(). share | improve...
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Debugging App When Launched by Push Notification

...opdown. (⌘+<) Than choose your product - 'Run MyApp.app' on the left. Select 'Info' tab on the right. And finally choose "Wait for MyApp.app to launch" option. More here in "Customize Executables in the Scheme Editor" section. EDIT: In case you miss logs in GDB, see Louis Gerbarg's comment t...
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How to get last N records with activerecord?

...e-wise - at least not up to Rails 3.1. SomeModel.last(5) will execute the select statement without a limit, returning all records of SomeModel to Ruby as an array, after which Ruby will pick out the last (5) elements. Efficiency-wise, currently, you want to use limit - particularly if you have pote...