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Add unique constraint to combination of two columns
I have a table and, somehow, the same person got into my Person table twice. Right now, the primary key is just an autonumber but there are two other fields that exist that I want to force to be unique.
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Remove rows with all or some NAs (missing values) in data.frame
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but using complete.cases is quite a lot more clear, and faster.
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Rails migration: t.references with alternative name?
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This works on Rails 5.1 and none of the other suggestions do. It's much cleaner, and feels right.
– stephenmurdoch
May 6 '17 at 2:03
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Remove Trailing Spaces and Update in Columns in SQL Server
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I am using SQL Management Studio v17.8.1 and while I get Intellisense for the TRIM function, when I execute it, it says it is not valid. I had to use the code above. Weird.
– DesertFoxAZ
Nov 2 '18 at 17:05
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How can I tell jackson to ignore a property for which I don't have control over the source code?
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Edit:
Thanks to the comments, with Jackson 2.5+, the API has changed and should be called with objectMapper.addMixIn(Class<?> target, Class<?> mixinSource)
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Declaration/definition of variables locations in ObjectiveC?
Ever since starting to work on iOS apps and objective C I've been really puzzled by the different locations where one could be declaring and defining variables. On one hand we have the traditional C approach, on the other we have the new ObjectiveC directives that add OO on top of that. Could you fo...
How to properly URL encode a string in PHP?
I'm making a search page, where you type a search query and the form is submitted to search.php?query=your query . What PHP function is the best and that I should use for encoding/decoding the search query?
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What is the right way to check for a null string in Objective-C?
...wing warning: comparison of distinct Objective-C types 'struct NSNull *' and 'struct NSString *' lacks a cast Is there any way of removing this (I dunno if things have changed since this question was asked)?
– thebossman
Dec 2 '10 at 1:40
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I lose my data when the container exits
Despite Docker's Interactive tutorial and faq I lose my data when the container exits.
11 Answers
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Intercepting links from the browser to open my Android app
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Use an android.intent.action.VIEW of category android.intent.category.BROWSABLE.
From Romain Guy's Photostream app's AndroidManifest.xml,
<activity
android:name=".PhotostreamActivity"
android:label="@string...