As name suggests,it is use to extract some part of string or character from string/expression.
Here substring require three parameters
1. expression – Can be string, character, binary,text or column name from table.
2. starting-point – Its integer value that represents starting point of the expression.
3. end-point – It represents that how many character you want to extract from expression.
select ‘Output’ = substring(‘Hello World’,6,len(‘hello world’))