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What's the difference between identifying and non-identifying relationships?
...t been able to fully grasp the differences. Can you describe both concepts and use real world examples?
15 Answers
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What is the benefit of using Fragments in Android, rather than Views?
When developing for Android , you can set your target (or minimum) sdk to 4 (API 1.6) and add the android compatibility package (v4) to add support for Fragments . Yesterday I did this and successfully implemented Fragments to visualize data from a custom class.
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Performance surprise with “as” and nullable types
...'m just revising chapter 4 of C# in Depth which deals with nullable types, and I'm adding a section about using the "as" operator, which allows you to write:
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How to center align the cells of a UICollectionView?
I am currently using UICollectionView for the user interface grid, and it works fine. However, I'd like to be enable horizontal scrolling. The grid supports 8 items per page and when the total number of items are, say 4, this is how the items should be arranged with horizontal scroll direction ena...
NULL values inside NOT IN clause
...t I thought were identical queries one using a not in where constraint and the other a left join . The table in the not in constraint had one null value (bad data) which caused that query to return a count of 0 records. I sort of understand why but I could use some help fully grasping the con...
Getting random numbers in Java [duplicate]
I would like to get a random value between 1 to 50 in Java.
2 Answers
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boost::flat_map and its performance compared to map and unordered_map
...haven't been able to find any performance comparisons. How does it compare and what are the best use cases for it?
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Should I use pt or px?
What is the difference between pt and px in CSS? Which one should I use and why?
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Linux command (like cat) to read a specified quantity of characters
Is there a command like cat in linux which can return a specified quantity of characters from a file?
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How do DATETIME values work in SQLite?
I’m creating Android apps and need to save date/time of the creation record. The SQLite docs say, however, "SQLite does not have a storage class set aside for storing dates and/or times" and it's "capable of storing dates and times as TEXT, REAL, or INTEGER values".
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