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How do I update if exists, insert if not (AKA “upsert” or “merge”) in MySQL?
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INSERT INTO `usage`
(`thing_id`, `times_used`, `first_time_used`)
VALUES
(4815162342, 1, NOW())
ON DUPLICATE KEY UPDATE
`times_used` = `times_used` + 1
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Media Queries - In between two widths
...a queries to make a class that only appears when the width is greater than 400px and less than 900px. I know this is probably extremely simple and I am missing something obvious, but I can't figure it out. What I have come up with is the below code, appreciate any help.
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Why isn't there a Guid.IsNullOrEmpty() method
...eople.
– Jon Skeet
Mar 23 '12 at 10:42
2
@goths You can make a general extension method for all v...
How can I replace a regex substring match in Javascript?
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4 Answers
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val-mutable versus var-immutable in Scala
...aniel C. SobralDaniel C. Sobral
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What does the caret (‘^’) mean in C++/CLI?
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answered Oct 14 '08 at 19:20
Rob WalkerRob Walker
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Insert a row to pandas dataframe
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149
Just assign row to a particular index, using loc:
df.loc[-1] = [2, 3, 4] # adding a row
df.i...
How do I convert a Ruby class name to a underscore-delimited symbol?
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Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
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143
Yes, it's subassignment in R using <- (or = or ->) that makes a copy of the whole object....
virtualenvwrapper and Python 3
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unutbuunutbu
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