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Difference between float and decimal data type
...If you divide 100 by 3 you don't get a rational number without a repeating set of trailing digits, so you can't multiply it by 3 and get 100. Get out a calculator and try it. Logically we know 1/3 + 1/3 + 1/3 should equal 3/3rds IE: 1, but this class of rational numbers doesn't allow us to do this.T...
In the shell, what does “ 2>&1 ” mean?
...about noclobber option and >| syntax###
That's about overwriting:
While set -o noclobber instruct bash to not overwrite any existing file, the >| syntax let you pass through this limitation:
$ testfile=$(mktemp /tmp/testNoClobberDate-XXXXXX)
$ date > $testfile ; cat $testfile
Mon Jan 7 13...
How to change Git log date formats
...dable format,
such as when using "--pretty". log.date config variable
sets a default value for log command’s --date option.
--date=relative shows dates relative to the current time, e.g. "2 hours ago".
--date=local shows timestamps in user’s local timezone.
--date=iso (or --date=iso8601)...
Fast check for NaN in NumPy
I'm looking for the fastest way to check for the occurrence of NaN ( np.nan ) in a NumPy array X . np.isnan(X) is out of the question, since it builds a boolean array of shape X.shape , which is potentially gigantic.
...
Difference between Math.Floor() and Math.Truncate()
What is the difference between Math.Floor() and Math.Truncate() in .NET?
12 Answers
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How do you check what version of SQL Server for a database using TSQL?
...mentioned in the answer posted by Matt Rogish:
DECLARE @ver nvarchar(128)
SET @ver = CAST(serverproperty('ProductVersion') AS nvarchar)
SET @ver = SUBSTRING(@ver, 1, CHARINDEX('.', @ver) - 1)
IF ( @ver = '7' )
SELECT 'SQL Server 7'
ELSE IF ( @ver = '8' )
SELECT 'SQL Server 2000'
ELSE IF ( @v...
Node.js - getting current filename
How to get current file name, function name and line number?
8 Answers
8
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How to find third or nth maximum salary from salary table?
How to find third or nth maximum salary from salary table(EmpID,EmpName,EmpSalary) in Optimized way?
54 Answers
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How to convert a char array to a string?
Converting a C++ string to a char array is pretty straightorward using the c_str function of string and then doing strcpy . However, how to do the opposite?
...
MySQL remove all whitespaces from the entire column
...
To replace all spaces :
UPDATE `table` SET `col_name` = REPLACE(`col_name`, ' ', '')
To remove all tabs characters :
UPDATE `table` SET `col_name` = REPLACE(`col_name`, '\t', '' )
To remove all new line characters :
UPDATE `table` SET `col_name` = REPLACE(`c...