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MongoDB not equal to
...y"})
db.test.find({'post': {$ne : ""}})
{ "_id" : ObjectId("4f68b1a7768972d396fe2268"), "author" : "you", "post" : "how to query" }
And now $not, which takes in predicate ($ne) and negates it ($not):
db.test.find({'post': {$not: {$ne : ""}}})
{ "_id" : ObjectId("4f68b19c768972d396fe2267"), "autho...
Html.Textbox VS Html.TextboxFor
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edited Sep 3 '14 at 9:21
answered May 6 '11 at 8:15
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How do android screen coordinates work?
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Overlaying histograms with ggplot2 in R
I am new to R and am trying to plot 3 histograms onto the same graph.
Everything worked fine, but my problem is that you don't see where 2 histograms overlap - they look rather cut off.
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MySQL Fire Trigger for both Insert and Update
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ConnectionTimeout versus SocketTimeout
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edited Sep 21 '18 at 17:53
answered Sep 9 '11 at 11:24
Rob...
passing several arguments to FUN of lapply (and others *apply)
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answered Jan 20 '13 at 17:41
Jonathan ChristensenJonathan Christensen
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Swift - Convert to absolute value
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Tamás Sengel
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answered Jun 11 '14 at 9:48
B.S.B.S.
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Is there a better way to write this null check, and a non-empty check, in groovy?
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