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MySQL - SELECT WHERE field IN (subquery) - Extremely slow why?
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Rewrite the query into this
SELECT st1.*, st2.relevant_field FROM sometable st1
INNER JOIN sometable st2 ON (st1.relevant_field = st2.relevant_field)
GROUP BY st1.id /* list a unique sometable field here*/
HAVING COUNT(*) > ...
What does (x ^ 0x1) != 0 mean?
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The XOR operation (x ^ 0x1) inverts bit 0. So the expression effectively means: if bit 0 of x is 0, or any other bit of x is 1, then the expression is true.
Conversely the expression is false if x == 1.
So the test is the same as:
if (x != 1)
and is therefo...
Add .gitignore to gitignore
Is it possible to add the .gitignore file to .gitignore itself?
6 Answers
6
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Google Play Services Library update and missing symbol @integer/google_play_services_version
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For everyone using Eclipse, this is how you should do it.
Eclipse -> import -> existing android code -> browse -> navigate to google-play-services_lib FOLDER (android-sdk/extras/google/google_play_services/libproject).
Then, on your project
control click -&...
Break a previous commit into multiple commits
Without creating a branch and doing a bunch of funky work on a new branch, is it possible to break a single commit into a few different commits after it's been committed to the local repository?
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Why is an int in OCaml only 31 bits?
Haven't seen this "feature" anywhere else. I know that the 32nd bit is used for garbage collection. But why is it that way only for ints and not for the other basic types?
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What is a race condition?
When writing multithreaded applications, one of the most common problems experienced is race conditions.
18 Answers
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Passing enum or object through an intent (the best solution)
I have an activity that when started needs access to two different ArrayLists. Both Lists are different Objects I have created myself.
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How can I access Google Sheet spreadsheets only with Javascript?
...oogle spreadsheet data (if they are published) via the JSON api:
https://github.com/mikeymckay/google-spreadsheet-javascript
You can see it in action here:
http://mikeymckay.github.com/google-spreadsheet-javascript/sample.html
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How to use permission_required decorators on django class-based views
I'm having a bit of trouble understanding how the new CBVs work. My question is this, I need to require login in all the views, and in some of them, specific permissions. In function-based views I do that with @permission_required() and the login_required attribute in the view, but I don't know how ...