INSTR FUNCTION

INSTR('Tech on the net', 'e')	would return 2; the first occurrence of 'e'
INSTR('Tech on the net', 'e', 1, 1)	would return 2; the first occurrence of 'e'
INSTR('Tech on the net', 'e', 1, 2)	would return 11; the second occurrence of 'e'
INSTR('Tech on the net', 'e', 1, 3)	would return 14; the third occurrence of 'e'
INSTR('Tech on the net', 'e', -3, 2)	would return 2