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Why there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT clause?
...TAMP and ON UPDATE
CURRENT_TIMESTAMP clauses. In addition, these clauses now can be used
with DATETIME column definitions. For more information, see Automatic
Initialization and Updating for TIMESTAMP and DATETIME.
http://dev.mysql.com/doc/relnotes/mysql/5.6/en/news-5-6-5.html
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How do you format the day of the month to say “11th”, “21st” or “23rd” (ordinal indicator)?
I know this will give me the day of the month as a number ( 11 , 21 , 23 ):
19 Answers
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How can I recover a removed file in Mercurial (if at all)?
...<revision number> <path to deleted file>
The deleted file will now be in your working copy, ready to be committed back into head.
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config.assets.compile=true in Rails production, why not?
...Also, someone would have to pay the price of slow asset delivery for an unknown period of time until all the assets are compiled and in place.
The default, where the price of compiling everything is paid off-line at one time, does not impact public visitors and ensures that everything works before ...
Why use getters and setters/accessors?
...erns. And what other objects (breaks) the method notifies I don't want to know either.
– sbi
Aug 24 '12 at 9:35
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How can I do time/hours arithmetic in Google Spreadsheet?
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Brilliant answer. Do you know if it is possible to do Format/Number/Normal within a formula (e.g., =Format.Number.Normal(A3))? Without that, I need to create a duplicate column of the hour column with the normal formatting.
– us...
How to store arrays in MySQL?
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Yes, which is how the example is setup now. Any information about the person should be in the person table, any information about the fruit in the fruits table, and any information specifically about the relationship between a particular person and a particular fr...
How do I pass a variable by reference?
...ight, but if you rebind the reference in the method, the outer scope will know nothing about it, and after you're done, the outer reference will still point at the original object.
If you pass an immutable object to a method, you still can't rebind the outer reference, and you can't even mutate the...
Android Studio - Ambiguous method call getClass()
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I think it is a bug in Android Studio. As we know, Android Studio is based on the IntelliJ Platform and the existing functionality of IntelliJ IDEA Community Edition.
Google has developed it in cooperation with JetBrains. And same bug is reported to happen in IntelliJ a...
Summarizing multiple columns with dplyr? [duplicate]
...x. I have a data frame with different variables and one grouping variable. Now I want to calculate the mean for each column within each group, using dplyr in R.
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