Question

I have a table called Employees:

BeginYear  |   EndYear   |    Name
1974           1983           Robert

For each record in Employees I need to insert each year into a new table called EmployeeYears

So:

For Each Record in Employees
    For i as int = Begin Year to End year
        INSERT i, Name into EmployeeYears

Any Way to do this in SQL…possibly with cursors?

Answer 1

The gist of it is using a WITH statement to create all the records and use them to insert into your final table.

;WITH q AS (
  SELECT Year = BeginYear
         , Name
  FROM   Employees
  UNION ALL
  SELECT q.Year + 1
         , q.Name
  FROM   q
         INNER JOIN Employees e ON e.Name = q.Name
                                   AND e.EndYear > q.Year
)
INSERT INTO EmployeeYears
SELECT * FROM q
OPTION(MAXRECURSION 0)

Testdata

CREATE TABLE Employees (BeginYear INTEGER, EndYear INTEGER, Name VARCHAR(32))
CREATE TABLE EmployeeYears (Year INTEGER, Name VARCHAR(32))

INSERT INTO Employees
  SELECT 1974, 1976, 'Robert'
  UNION ALL SELECT 1972, 1975, 'Lieven'

Results

SELECT  *
FROM    EmployeeYears
ORDER BY Name, Year

1972    Lieven
1973    Lieven
1974    Lieven
1975    Lieven
1974    Robert
1975    Robert
1976    Robert