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Showing posts with the label SQL query Optimization or Query Evalution

SQL query Optimization or Query Evalution

Note: I have performed on oracle 10g wonder whether it will work on oracle 9i. SQL> set autotrace on; SQL> create table sailors (sid number(5) primary key, sname varchar2(10), rating number(5), age number(5)); Table created. SQL> create table reserves (sid number(5) , did number(5), day number(5), rname varchar2(5), CONSTRAINT col3_fk FOREIGN KEY(sid) REFERENCES sailors(sid) ON DELETE CASCADE); Table created. SQL> select * from sailors;        SID SNAME          RATING        AGE ---------- ---------- ---------- ----------          1 asss                1         22          2 adfss             ...