Chapter 14 - Join Indexes
“Every sunrise is a second chance”
Creating a Multi-Table Join Index
CREATE JOIN INDEX EMP_DEPT_IDX AS SELECT Employee_No ,E.Dept_No ,First_Name ,Last_Name ,Salary ,Department_Name FROM Employee_Table as E INNER JOIN Department_Table as D ON E.Dept_No = D.Dept_No PRIMARY INDEX (Employee_No) ;
The Syntax above will create a Multi-Table Join Index with a NUPI on Employee_No. The next slide will illustrate a visual so you can see the data in the Join Index. Join Indexes are created so data doesn't have to move to satisfy the join. The Join Index essentially pre-joins the table and keeps it hidden for the Parsing Engine to utilize.
Visual of a Join Index
The Join Index looks like an Answer Set, but each ...