Example of SQL Server Date Difference Calculation - MINUTE

1. Find the number of MINUTE between two dates with format Date - yyyy-mm-dd
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DECLARE @d1 DATETIME, @d2 DATETIME
SELECT
    @d1 = '2011-01-01 00:00:01',
    @d2 = '2011-01-02 23:59:00'
   
SELECT
    DATEDIFF(minute, @d1, @d2) AS MinuteDiff
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-----code:end-----
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Result Messages:
MinuteDiff
-----------
2879

(1 row(s) affected)



2. Find the number of MINUTE between two dates with format Date - mm/dd/yyyy
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-----code:start-----
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DECLARE @d1 DATETIME, @d2 DATETIME
SELECT
    @d1 = '1/1/2011 00:00:01',
    @d2 = '1/2/2011 23:59:00'
   
SELECT
    DATEDIFF(minute, @d1, @d2) AS MinuteDiff
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-----code:end-----
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Result Messages:
MinuteDiff
-----------
2879

(1 row(s) affected)



3. Find the number of MINUTE between two dates with format Date - dd-mmm-yyyy
-----------------------------------------------------------------------
-----code:start-----
-----------------------------------------------------------------------
DECLARE @d1 DATETIME, @d2 DATETIME
SELECT
    @d1 = '01-Jan-2011 00:00:01',
    @d2 = '02-Jan-2011 23:59:00'
   
SELECT
    DATEDIFF(minute, @d1, @d2) AS MinuteDiff
-----------------------------------------------------------------------
-----code:end-----
-----------------------------------------------------------------------

Result Messages:
MinuteDiff
-----------
2879

(1 row(s) affected)


Source:
http://syntaxhelp.com/SQLServer/DATEDIFF