Usage of SQL CHARINDEX

CHARINDEX returns a starting position of a string which helps developer to split a data based on the requirement. Below is an example of CHARINDEX usage:

DECLARE @AMT Varchar(50) = '$50K - $70K'
SELECT REPLACE(SUBSTRING('$50K - $70K',charindex('$', '$50K - $70K')+1, charindex('K', @AMT)),'K','') AS MinRange
,REPLACE(SUBSTRING('$50K - $70K',charindex('-', '$50K - $70K')+3, charindex('K', @AMT)),'K','') As MaxRange
The output is:
----------------------------------
MinRange      MaxRange
-----------------------------------
50        &n bsp;          70
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