Given a QDEL table from QSALE DB provide as many alternative ways (queries with different execution/explain plan) to perform the following task (problem pattern): select every 5th record.
Make sure to test your code and demonstrate validity of each solution.
a) Given a QITEM table from QSALE DB copy its content into NEWITEM table.
b) Make three unrelated and elementary changes (one record update, one new record insert, and one old record delete) making sure you do not leave any duplicates.
c) Provide as many different ways using SQL to accomplish following task: compare the tables QITEM and NEWITEM to assess if they are exactly the same. Make sure to test each of your solutions.
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