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SQLite table constraint - unique on multiple columns
I can find syntax "charts" on this on the SQLite website, but no examples and my code is crashing. I have other tables with unique constraints on a single column, but I want to add a constraint to the table on two columns. This is what I have that is causing an SQLiteException with the message "syn...
How to programmatically set the layout_align_parent_right attribute of a Button in Relative Layout?
I have a relative layout which I am creating programmatically:
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Rails auto-assigning id that already exists
I create a new record like so:
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val-mutable versus var-immutable in Scala
Are there any guidelines in Scala on when to use val with a mutable collection versus using var with an immutable collection? Or should you really aim for val with an immutable collection?
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Copy multiple files in Python
How to copy all the files present in one directory to another directory using Python.
I have the source path and the destination path as string.
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Order data frame rows according to vector with specific order
Is there an easier way to ensure that a data frame's rows are ordered according to a "target" vector as the one I implemented in the short example below?
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image.onload event and browser cache
I want to create an alert box after an image is loaded, but if the image is saved in the browser cache, the .onload event will not be fired.
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Postgres: Distinct but only for one column
I have a table on pgsql with names (having more than 1 mio. rows), but I have also many duplicates. I select 3 fields: id , name , metadata .
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Using Core Data, iCloud and CloudKit for syncing and backup and how it works together
I am in the early stages of creating an app where I would like to save, sync and backup data. The app will not store any files just data in a database. It is going to be iOS 8 and up so I am able to use CloudKit. I did some research and still not clear on how Core Data, iCloud and CloudKit work to...
When to use os.name, sys.platform, or platform.system?
As far as I know, Python has 3 ways of finding out what operating system is running on:
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