PATINDEX: The PATINDEX functions return the starting position of a pattern you specify.
You must include percent signs before and after the pattern,
Unless you are looking for the pattern as the first (omit the first %) or last (omit the last %) characters in a column or text.
PATINDEX ( '%pattern%' , expression )
Pattern: Pattern is a character expression that contains sequence of the characters. Wildcard characters can be used.
Expression: The expression that is searched for the specified pattern.
SELECT PATINDEX('%e____le%', 'This example of the Patindex');
Note: PATINDEX works just like LIKE, so you can use any of the wildcards. You do not have to enclose the pattern between percents. PATINDEX('a%', 'abc') returns 1 and PATINDEX('%a', 'cba') returns 3.
Unlike LIKE, PATINDEX returns a position, similar to what CHARINDEX does.