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Difference between dispatch_async and dispatch_sync on serial queue?
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3 Answers
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SQL: How to get the count of each distinct value in a column?
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318
SELECT
category,
COUNT(*) AS `num`
FROM
posts
GROUP BY
category
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How to tell if rails is in production?
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33
2 easy ways:
tail -f log/production.log
if there are entries populating that log after you h...
Sublime Text 2 and 3: open the same file multiple times
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30
Go into the pane you want to see the file in.
Type Ctrl-p (Mac: ⌘-p) to get the list of file...
How can I filter a Django query with a list of values?
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3 Answers
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Active
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How can I use if/else in a dictionary comprehension?
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31
Worth mentioning that you don't need to have an if-else condition for both the key and the value. For example, {(a if condition else b): v...
How can I loop through a List and grab each item?
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answered Sep 18 '13 at 3:08
Simon WhiteheadSimon Whitehead
54.9k66 gold badges8383 silver badges119119 bronze badges
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What is the _snowman param in Ruby on Rails 3 forms for?
In Ruby on Rails 3 (currently using Beta 4), I see that when using the form_tag or form_for helpers there is a hidden field named _snowman with the value of ☃ ( Unicode \x9731) showing up.
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