Example.QueryMonad

some queries implemented using the list monad

A special Table type instead of plain lists could provide an efficient implementation.

Documentation

employees :: [Emp]

all employees

clerks :: [Emp]

all clerks

richClerks :: [Emp]

all clerks with salary at least 1000

researchers :: [Emp]

all employees in research department

researchers0 :: [Emp]

managers :: [(String, String)]

names of all employees and their managers if the employee has a manager so far

managers0 :: [(String, String)]

names of all employees and their managers; if the employee has no manager, return an empty string

realManagers :: [String]

names of managers that have at least one employee

realManagersFull :: [Emp]

managers that have at least one employee

realManagersSortedFull :: [Emp]

managers that have at least one employee, sorted by their names.

maximumSalary :: Int

maximum salary amongst all employees

richestEmployee :: Emp

employee with maximum salary without a back-join

teams :: [(String, [String])]

employees grouped by their managers implemented with a sub-query

teams0 :: [(String, [String])]

employees grouped by their managers implemented with a GROUP BY

averageSalariesInDepartments :: [(String, Int)]

average salary in each department

managerOfLargestTeam :: (String, Int)

manager with most employees

teamSalaries0 :: [(String, Int)]

A recursive query: Compute the total salary for each manager and the total set of employees he conducts.

teamSalaries :: [(String, Int)]