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How do I update if exists, insert if not (AKA “upsert” or “merge”) in MySQL?
Is there an easy way to INSERT a row when it does not exist, or to UPDATE if it exists, using one MySQL query?
2 Answer...
Append TimeStamp to a File Name
...e:
string result = "myFile_" + DateTime.Now.ToFileTime() + ".txt";
What does ToFileTime() do?
Converts the value of the current DateTime object to a Windows file time.
public long ToFileTime()
A Windows file time is a 64-bit value that represents the number of 100-nanosecond interv...
'Specified condition “$(PackageAsSingleFile)” evaluates to “” instead of a boolean?
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Restarting VS usually helps, but when it doesn't - try deleting .user and .suo files, as per this suggestion: https://stackoverflow.com/a/16223645/913845
This does not always work, however if you skip "Preview Deployment" it is less likely to fail.
Probably it's t...
Two versions of python on linux. how to make 2.7 the default
...already created a new symb link as per @rohit's answer. Now my yum command doesn't work! I tried creating the sym link back but it doesn't work sudo ln -sf /usr/bin/python2.6 /usr/bin/python any workaround?
– Anthony
Oct 8 '13 at 22:39
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Debug a java application without starting the JVM with debug arguments
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link does not work.... maybe you outa remove the http:// before the https://... I would've but dont have the enough reputation yet
– Newtopian
Dec 17 '08 at 23:05
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Make page to tell browser not to cache/preserve input values
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I talk about checkboxes so I can't set value to "". And, does autocomplete off means not to store form input values "when user presses F5", not only "for dropdown autocompletion list"?
– queen3
Apr 23 '10 at 17:20
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Time complexity of Euclid's Algorithm
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What does n represent?
– IVlad
Oct 20 '10 at 17:11
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How do I find the number of arguments passed to a Bash script?
... @kaanyılmaz: The only problem with that is that Bash only does integer arithmetic. If you want decimals, you will need to use AWK, bc, or something else (ksh93 and zsh can also do decimal math). Your code includes dollar signs for some variables, but not others. You should be consis...
Why isn't there a Guid.IsNullOrEmpty() method
This keeps me wondering why Guid in .NET does not have IsNullOrEmpty() method (where empty means all zeros)
6 Answers
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Numpy: Divide each row by a vector element
... 3
vector reshaped: 3 x 1
Note that data/vector is ok, but it doesn't get you the answer that you want. It divides each column of array (instead of each row) by each corresponding element of vector. It's what you would get if you explicitly reshaped vector to be 1x3 instead of 3x1.
dat...