INSTR « Character String Functions « Oracle PL/SQL Tutorial

11.6.1.INSTR(x, find_string [, start] [, occurrence]) searchs for find_string in x
11.6.2.INSTR ('in-string') is a function used to find patterns in strings
11.6.3.Display the position where the second occurrence of e occurs in employee's first name
11.6.4.INSTR returns a location within the string where search pattern begins.
11.6.5.Look for the second occurrence of 'is'
11.6.6.If search pattern is not in the string, the INSTR function returns 0
11.6.7.Using SUBSTR and INSTR together
11.6.8.If the INSTR pattern is not found, then the entire string would be returned
11.6.9.Use dates in INSTR functions

11.6.10.instr and substr