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How to check if an array field contains a unique value or another array in MongoDB?
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db.blogpost.find({ 'tags' : 'tag1'}); //1
db.blogpost.find({ 'tags' : { $all : [ 'tag1', 'tag2' ] }}); //2
db.blogpost.find({ 'tags' : { $in : [ 'tag3', 'tag4' ] }}); //3
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How to loop through all but the last item of a list?
... would indicate I answered the question he asked, if not the question he really wanted to ask. Asker is welcome to demote this answer.
– freespace
May 27 '09 at 11:35
7
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How do multiple clients connect simultaneously to one port, say 80, on a server? [duplicate]
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First off, a "port" is just a number. All a "connection to a port" really represents is a packet which has that number specified in its "destination port" header field.
Now, there are two answers to your question, one for stateful protocols and one for stateless...
How to get number of rows using SqlDataReader in C#
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There are only two options:
Find out by reading all rows (and then you might as well store them)
run a specialized SELECT COUNT(*) query beforehand.
Going twice through the DataReader loop is really expensive, you would have to re-execute the query.
And (thanks to Pete ...
How to handle exceptions in a list comprehensions?
...n alternate values &c in case of exceptions), so it's impossible, literally speaking, to "handle exceptions in a list comprehension" because a list comprehension is an expression containing other expression, nothing more (i.e., no statements, and only statements can catch/ignore/handle exception...
How to use Python's pip to download and keep the zipped files for a package?
...the pip command to download a package (and its dependencies), but keep all of the zipped files that get downloaded (say, django-socialregistration.tar.gz) - is there a way to do that?
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Why shouldn't all functions be async by default?
...kind words. It is indeed an awesome feature and I am glad to have been a small part of it.
If all my code is slowly turning async, why not just make it all async by default?
Well, you're exaggerating; all your code isn't turning async. When you add two "plain" integers together, you're not awa...
Are default enum values in C the same for all compilers?
When declaring an enum as shown below, do all C compilers set the default values as x=0 , y=1 , and z=2 on both Linux and Windows systems?
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How to quit android application programmatically
I Found some codes for quit an Android application programatically. By calling any one of the following code in onDestroy() will it quit application entirely?
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Edit the root commit in Git?
...kout <sha1-of-root>
# amend the commit
git commit --amend
# rebase all the other commits in master onto the amended root
git rebase --onto HEAD HEAD master
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