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How do you query for “is not null” in Mongo?
...s:
db.test.insert({"num":1, "check":"check value"});
db.test.insert({"num":2, "check":null});
db.test.insert({"num":3});
This will return all three documents:
db.test.find();
This will return the first and second documents only:
db.test.find({"check":{$exists:true}});
This will return the first d...
Simpler way to create dictionary of separate variables?
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27 Answers
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Convert char to int in C#
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answered Apr 28 '09 at 2:20
Chad GrantChad Grant
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Display name of the current file in vim?
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201
:f (:file) will do same as <C-G>. :f! will give a untruncated version, if applicable.
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How do I get the number of elements in a list?
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2690
The len() function can be used with several different types in Python - both built-in types a...
Co-variant array conversion from x to y may cause run-time exception
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edited Feb 4 '15 at 16:27
answered Jan 2 '12 at 19:02
An...
How do I remove/delete a virtualenv?
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ivan_pozdeev
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answered Jun 12 '12 at 21:58
Thomas Antho...
Would you, at present date, use JBoss or Glassfish (or another) as Java EE server for a new project?
... including my favorite, Jetty.
Do you have to use any of the other major J2EE technologies like JMS, ESB, etc? If so, and you really can't do without, then you are again constrained to a full-blown J2EE container. Carefully think and investigate before you commit to BPM, for example, and avoid Aq...
Reading a List from properties file and load with spring annotation @Value
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Ahmed Ashour
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answered Sep 25 '12 at 9:41
Wilhelm KleuWilhelm Kleu
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