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Difference between Select Unique and Select Distinct
...is synonymous with SELECT DISTINCT.
Use SELECT DISTINCT because this is standard SQL, and SELECT UNIQUE is non-standard, and in database brands other than Oracle, SELECT UNIQUE may not be recognized at all.
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Display milliseconds in Excel
...rs which are timestamps in milliseconds (e.g. 28095200 is 7:48:15.200 am), and I want to make a new column next to it which keeps a running average and displays the time in a hh:mm:ss.000 format.
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Cost of exception handlers in Python
...nt division or modulo by zero
So, as expected, not having any exception handler is slightly faster (but blows up in your face when the exception happens), and try/except is faster than an explicit if as long as the condition is not met.
But it's all within the same order of magnitude and unlikel...
How does setting baselineAligned to false improve performance in LinearLayout?
I was just building some UI in xml, and Lint gave me a warning and said to set android:baselineAligned to false to improve performance in ListView.
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Minimum and maximum date
I was wondering which is the minimum and the maximum date allowed for a Javascript Date object. I found that the minimum date is something like 200000 B.C., but I couldn't get any reference about it.
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How many threads can a Java VM support?
... OS, on what other processes are doing, on what Java release you're using, and other factors. I've seen a Windows server have > 6500 Threads before bringing the machine down. Most of the threads were not doing anything, of course. Once the machine hit around 6500 Threads (in Java), the whole m...
Best practice to return errors in ASP.NET Web API
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For me I usually send back an HttpResponseException and set the status code accordingly depending on the exception thrown and if the exception is fatal or not will determine whether I send back the HttpResponseException immediately.
At the end of the day it's an API sending b...
Copy values from one column to another in the same table
...uestion is:
UPDATE `table` SET test=number
Here table is the table name and it's surrounded by grave accent (aka back-ticks `) as this is MySQL convention to escape keywords (and TABLE is a keyword in that case).
BEWARE, that this is pretty dangerous query which will wipe everything in column te...
IIS7 Overrides customErrors when setting Response.StatusCode?
...Code to whatever is appropriate. For example, if I make a custom 404 page and name it 404.aspx, I could put <% Response.StatusCode = 404 %> in the contents in order to make it have a true 404 status header.
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How to read the value of a private field from a different class in Java?
I have a poorly designed class in a 3rd-party JAR and I need to access one of its private fields. For example,
why should I need to choose private field is it necessary?
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