S.no SUBSTR (sub-string) INSTR (in-string)
1. It extracts the specific part of the string from the whole string It searches the entire string for finding the sub-string
2. The output data type is the number for the numeric input and the character for the date and the character input The output data type is always the number
3. The second argument is always the number The second argument should be a number or the character depending upon the data type of the input.
BY Best Interview Question ON 19 Feb 2019