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MySQL: selecting rows where a column is null
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SQL NULL's special, and you have to do WHERE field IS NULL, as NULL cannot be equal to anything,
including itself (ie: NULL = NULL is always false).
See Rule 3 https://en.wikipedia.org/wiki/Codd%27s_12_rules
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Google Gson - deserialize list object? (generic type)
...n<...>() {}.getType() captures a compile-time type (between the < and >) into a runtime java.lang.reflect.Type object. Unlike a Class object, which can only represent a raw (erased) type, the Type object can represent any type in the Java language, including a parameterized instantiation...
How do I delete a fixed number of rows with sorting in PostgreSQL?
...'t change ctids, I don't think. Since that just compacts within each page, and the ctid is just the line number not a page offset. A VACUUM FULL or a CLUSTER operation would change the ctid, but those operations take an access exclusive lock on the table first.
– araqnid
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How to add to an existing hash in Ruby
...ash in Ruby, I'm in the process of working through Apress' Beginning Ruby and have just finished the hashes chapter.
7 Ans...
How to get a specific version of a file in Mercurial?
I am new to Mercurial. Just cannot find the right command. Tried update/checkout with no luck. I am using local repository. Thanks
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What could cause java.lang.reflect.InvocationTargetException?
Well, I've tried to understand and read what could cause it but I just can't get it:
13 Answers
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warning: Insecure world writable dir /usr/local/bin in PATH, mode 040777
Every time I run this command rails server :
12 Answers
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Add single element to array in numpy
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This command does not alter the a array. However, it returns a new modified array. So, if a modification is required then a = numpy.append(a,a[0]) must be used.
– Amjad
Oct 16 '17 at 15:24
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Packing NuGet projects compiled in release mode?
...modified in the project file directly (no VS GUI option). To avoid the command-line property tweak for all future nuget pack calls, edit the project file XML in your favorite text editor.
– patridge
Jun 30 '11 at 22:07
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How to get share counts using graph API
I can get the share count of an URL using PHP SDK and using the deprecated rest API, but didn't find a way to get the share counts of an URL using graph API.
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