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ETag vs Header Expires
...d around but haven't been able to figure out if I should use both an ETag and an Expires Header or one or the other.
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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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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...
How to change the CHARACTER SET (and COLLATION) throughout a database?
... table (Mysql). He set it up with Latin collation, when it should be UTF8, and now I have issues. Every record with Chinese and Japan character turn to ??? character.
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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?
9 Answers
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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...
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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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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How to set HTTP headers (for cache-control)?
...ive CACHE-CONTROL:NO-CACHE indicates cached information should not be used
and instead requests should be forwarded to the origin server. This directive has the same semantics as the PRAGMA:NO-CACHE.
Clients SHOULD include both PRAGMA: NO-CACHE and CACHE-CONTROL: NO-CACHE when a no-cache request is...
How to get users to read error messages?
...ind yourself at a high risk that users will not read your carefully worded and enlightening error messages, but just click on the first button available with a shrug of frustration.
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