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Functions
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Data Types
date
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string
Compatibility
SUM(f)
Engine OK Alternative
mysql yes
oracle yes
postgres yes
sqlserver yes

SUM

SUM adds a whole column of values.

SUM is an aggregate function it is normally used with GROUP BY. 

  SELECT region, SUM(population)
    FROM bbc
   GROUP BY region
With a GROUP BY region statement each region shows up just once. The SUM column gives the total for each region.

Results
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