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What's the $unwind operator in MongoDB?
... the following:
db.article.aggregate(
{ $project : {
author : 1 ,
title : 1 ,
tags : 1
}},
{ $unwind : "$tags" }
);
would return the following documents:
{
"result" : [
{
"_id" : ObjectId("4e6e4ef557b77501a49233f6"),
...
How to delete from select in MySQL?
...
210
SELECT (sub)queries return result sets. So you need to use IN, not = in your WHERE clause.
Add...
Drawing a dot on HTML5 canvas [duplicate]
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143
For performance reasons, don't draw a circle if you can avoid it. Just draw a rectangle with a...
Best way to parseDouble with comma as decimal separator?
...
10 Answers
10
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Select mySQL based only on month and year
...n my mySQL DB that has some rows. One of this row is a DATE, like this: 2012-02-01
12 Answers
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Only read selected columns
...
157
Say the data are in file data.txt, you can use the colClasses argument of read.table() to skip...
VBoxManage: error: Failed to create the host-only adapter
I am running vagrant 1.4 and virtual box 4.3 on fedora 17 machine. When I do "vagrant up", I get this error:
32 Answers...
How can I get file extensions with JavaScript?
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How to select multiple rows filled with constants?
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15 Answers
15
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