SQL Server supports 2 categories of user defined functions based on their return modes:

1. Scalar-valued Functions - A function that returns a single value. Scalar-valued functions can be used in scalar expressions. Below are some scalar-valued functions:

PRINT GETDATE();

GO

May 19 2007 1:26PM

PRINT 'URL reversed: '+REVERSE('rendc.org');

GO

URL reversed: moc.enilediuglabolg

2. Table-valued Functions - A function that returns data in rows and columns like a table. Table-valued functions can be used in table expressions like the FROM clause of SELECT statements Below are some scalar-valued functions:

SELECT * FROM fn_helpcollations() WHERE name LIKE 'French_CI%'

GO

name

-------------------

French_CI_AI

French_CI_AI_WS

French_CI_AI_KS

French_CI_AI_KS_WS

French_CI_AS

French_CI_AS_WS

French_CI_AS_KS

French_CI_AS_KS_WS

(8 row(s) affected)