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Return a value if no rows are found in Microsoft tSQL
Using a Microsoft version of SQL, here's my simple query. If I query a record that doesn't exist then I will get nothing returned. I'd prefer that false (0) is returned in that scenario. Looking for the simplest method to account for no records.
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Checking if a variable is an integer
Does Rails 3 or Ruby have a built-in way to check if a variable is an integer?
11 Answers
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How do I iterate through each element in an n-dimensional matrix in MATLAB?
...dx = 1:numel(array)
element = array(idx)
....
end
This is useful if you don't need to know what i,j,k, you are at. However, if you don't need to know what index you are at, you are probably better off using arrayfun()
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handlerbars.js check if list is empty
Is there a way in Handlebars.js templating to check if the collection or list is null or empty, before going and iterating through the list/collection?
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Javascript shorthand ternary operator
...ber || 1;
Something like that what you're looking for, where it defaults if undefined?
var foo = bar || 1; // 1
var bar = 2;
foo = bar || 1; // 2
By the way, this works for a lot of scenarios, including objects:
var foo = bar || {}; // secure an object is assigned when bar is absent
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Is “else if” a single keyword?
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They are not a single keyword if we go to the draft C++ standard section 2.12 Keywords table 4 lists both if and else separately and there is no else if keyword. We can find a more accessible list of C++ keywords by going to cppreferences section on keyw...
Truncate number to two decimal places without rounding
... happen with floating point values (and on the other side of the spectrum, if the number happens to be 15, sounds like the OP wants 15.00).
– T.J. Crowder
Nov 15 '10 at 17:38
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Java String - See if a string contains only numbers and not letters
...ication, and it changes from numbers to letters and such. I have a simple if statement to see if it contains letters or numbers but, something isn't quite working correctly. Here is a snippet.
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How do I daemonize an arbitrary script in unix?
...h this is standard out and standard error both get sent to ./nohup.out, so if you start several scripts in this manor their output will be intertwined. A better command would be:
nohup yourScript.sh script args >script.out 2>script.error&
This will send standard out to the file of your ...
Add a column to a table, if it does not already exist
...an use a similar construct by using the sys.columns table io sys.objects.
IF NOT EXISTS (
SELECT *
FROM sys.columns
WHERE object_id = OBJECT_ID(N'[dbo].[Person]')
AND name = 'ColumnName'
)
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