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How do you query for “is not null” in Mongo?
...k 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":{$exists:true}});
This will return the first document only:
db.test.find({"check":{$ne:...
How do I get a Date without time in Java?
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answered Feb 19 '11 at 10:35
Jon SkeetJon Skeet
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Is it possible to make anonymous inner classes in Java static?
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138
No, you can't, and no, the compiler can't figure it out. This is why FindBugs always suggests c...
libpng warning: iCCP: known incorrect sRGB profile
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13 Answers
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Is there a way to detect if a browser window is not currently active?
...swer, a new specification has reached recommendation status thanks to the W3C. The Page Visibility API (on MDN) now allows us to more accurately detect when a page is hidden to the user.
document.addEventListener("visibilitychange", onchange);
Current browser support:
Chrome 13+
Internet Expl...
How to remove all MySQL tables from the command-line without DROP database permissions? [duplicate]
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309
You can generate statement like this: DROP TABLE t1, t2, t3, ... and then use prepared stateme...
How do I call the default deserializer from a custom deserializer in Jackson
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+200
As StaxM...
download file using an ajax request
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edited May 23 '17 at 11:47
Community♦
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answered Dec 29 '13 at 21:39
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How can I distribute python programs?
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37
The normal way of distributing Python applications is with distutils. It's made both for distri...