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Ruby on Rails - The Maths Functions
Consider a table object called Person. This table is having fields like age, first_name, last_name and salary.
Following will return the average age of all the employees.
Person.average :age
The following will return the maximum age of the employees.
Person.maximum :age
The following will return minimum age of the employees.
Person.minimum :age
The following will return the sum of salaries of all the employees.
Person.sum :salary, :group => :last_name
The following will count the number of records having age more than 26.
Person.count(:conditions => "age > 26")
The following will count the total number of records.
Person.count
Check the Calculation Functions link for more detail on Calculation Functions.
rails-references-guide.htm
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