Be sure you know all the syntax, rules and DEFAULT values for defining and using sequences. It’s hard to know which functions the test will quiz you on, but be familiar with the basic ones including, but not limited to: TO_CHAR, NUMBER, SUBSTR, UPPER, LOWER, NVL, SUM, COUNT, DISTINCT. The more functions you know the better off you will be.
Understand the structures, use of different type of cursors, and error handling in PL/SQL. Also know how to use the GROUP BY and HAVING clauses.
Above all these chapter have been very tough to me. but now after passing exam 1Z0-147 somethings looks tough and confusionf to me................now is all clear.