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“Insert if not exists” statement in SQLite
I have an SQLite database. I am trying to insert values ( users_id , lessoninfo_id ) in table bookmarks , only if both do not exist before in a row.
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Why does Haskell's “do nothing” function, id, consume tons of memory?
Haskell has an identity function which returns the input unchanged. The definition is simple:
1 Answer
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How do I get a YouTube video thumbnail from the YouTube API?
...They are predictably formatted as follows:
https://img.youtube.com/vi/<insert-youtube-video-id-here>/0.jpg
https://img.youtube.com/vi/<insert-youtube-video-id-here>/1.jpg
https://img.youtube.com/vi/<insert-youtube-video-id-here>/2.jpg
https://img.youtube.com/vi/<insert-youtube-...
Migration: Cannot add foreign key constraint
I'm trying to create foreign keys in Laravel however when I migrate my table using artisan i am thrown the following error:
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Showing empty view when ListView is empty
For some reason the empty view, a TextView in this case, always appears even when the ListView is not empty. I thought the ListView would automatically detect when to show the empty view.
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Your content must have a ListView whose id attribute is 'android.R.id.list'
...layout_width="fill_parent"
android:layout_height="fill_parent"/>
Since you are using ListActivity your xml file must specify the keyword android while mentioning to a ID.
If you need a custom ListView then instead of Extending a ListActivity, you have to simply extend an Activity and shou...
For each row return the column name of the largest value
...have a roster of employees, and I need to know at what department they are in most often. It is trivial to tabulate employee ID against department name, but it is trickier to return the department name, rather than the number of roster counts, from the frequency table. A simple example below (column...
Rails :include vs. :joins
This is more of a "why do things work this way" question rather than a "I don't know how to do this" question...
8 Answers
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Single controller with multiple GET methods in ASP.NET Web API
In Web API I had a class of similar structure:
17 Answers
17
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Android: View.setID(int id) programmatically - how to avoid ID conflicts?
I'm adding TextViews programmatically in a for-loop and add them to an ArrayList.
14 Answers
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