Counting occurrences of a substring within a string in TSQL

original post: Counting occurrences of a substring within a string

SELECT dbo.GetSubstringCount('We like the autos, the autos that go boom.', 'auto', '')
-- Returns 2

SELECT dbo.GetSubstringCount('Autos are fun.  I like to drive my auto.', 'auto', '')
-- Also returns 2

SELECT dbo.GetSubstringCount('Autos are fun.  I like to drive my auto.', 'auto', '%[a-z]%')
-- Only returns 1 -- The exact match must not have adjacent alphabetic characters