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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...
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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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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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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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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Should I use pt or px?
What is the difference between pt and px in CSS? Which one should I use and why?
5 Answers
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How do I convert a column of text URLs into active hyperlinks in Excel?
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If you don't want to make a macro and as long as you don't mind an additional column, then just create a new column alongside your column of URLs.
In the new column type in the formula =HYPERLINK(A1) (replacing A1 with whatever cell you are interested in). T...
A simple scenario using wait() and notify() in java
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The wait() and notify() methods are designed to provide a mechanism to allow a thread to block until a specific condition is met. For this I assume you're wanting to write a blocking queue implementation, where you have some fixed size ...
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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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?
2 Answer...