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MySQL Fire Trigger for both Insert and Update
Is it possible to fire a mysql trigger for both the insert and update events of a table?
3 Answers
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R object identification
... often ending up with a function producing output for which I don't understand the output data type. I'm expecting a list and it ends up being a list of lists or a data frame or something else. What's a good method or workflow for figuring out the output data type when first using a function?
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Why can tuples contain mutable items?
...ghts to help complete your mental model of what tuples are, how they work, and their intended use:
Tuples are characterized less by their immutability and more by their intended purpose.
Tuples are Python's way of collecting heterogeneous pieces of information under one roof. For example,
s = ('...
leading zeros in rails
I have fields hr and min , both integers in my application. For hr field, if the user enters "1" I would like Rails to automatically pad it to "01" before saving it to the database. Also for the min field if the user enter "0" it should put in as "00".
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data.frame rows to a list
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Like this:
xy.list <- split(xy.df, seq(nrow(xy.df)))
And if you want the rownames of xy.df to be the names of the output list, you can do:
xy.list <- setNames(split(xy.df, seq(nrow(xy.df))), rownames(xy.df))
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How to convert Linux cron jobs to “the Amazon way”?
...s their response:
Tom
I did a quick poll of some of my colleagues and came up empty on the
cron, but after sleeping on it I realised the important step may be
limited to locking. So I looked for "distributed cron job locking"
and found a reference to Zookeeper, an Apache project.
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Best way to parse command line arguments in C#? [closed]
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I would strongly suggest using NDesk.Options (Documentation) and/or Mono.Options (same API, different namespace). An example from the documentation:
bool show_help = false;
List<string> names = new List<string> ();
int repeat = 1;
var p = new OptionSet () {
{ "n|name...
uint8_t vs unsigned char
... It wasn't clear in the original question if we were talking about a standard type or not. I'm sure there have been many variations of this naming convention over the years.
– Mark Ransom
Nov 12 '09 at 22:50
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What is the difference between JVM, JDK, JRE & OpenJDK?
...s the virtual machine that runs the Java bytecodes. The JVM doesn't understand Java source code; that's why you need compile your *.java files to obtain *.class files that contain the bytecodes understood by the JVM. It's also the entity that allows Java to be a "portable language" (write once, run ...
How Can I Set the Default Value of a Timestamp Column to the Current Timestamp with Laravel Migratio
...r/Migrations. I have gone through the Laravel documentation several times, and I don't see how I can make that the default for a timestamp column.
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