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Một khoản đâu được thêm vào bản Tuyên Bố Chú ý rằng NƠI đã loại trừ các hàng trước khi đặt hàng cuối cùng: SELECT empno, ename, orig_salary TỪ nhân viên NƠI orig_salary Một khoản đâu được thêm vào bản Tuyên Bố Chú ý rằng NƠI đã loại trừ các hàng trước khi đặt hàng cuối cùng:SELECT empno, ename, orig_salary TỪ nhân viên NƠI orig_salary | The Analytical Functions in Oracle Analytical Functions I A SELECT with Just a FROM Clause SELECT empno ename orig_salary FROM employee Gives EMPNO ENAME ORIG_SALARY 101 John 3 102 Stephanie 35000 104 Christina 43000 108 David 37000 111 Katie 45000 106 Chloe 33000 122 Lindsey 40000 A SELECT with Ordering Note that the ordering is applied to the result set after the result is established SELECT empno ename orig_salary FROM employee ORDER BY orig_salary Gives EMPNO ENAME ORIG_SALARY 106 Chloe 33. 101 John 35000 102 Stephanie 35000 108 David 37000 122 Lindsey 40000 104 Christina 43000 111 Katie 45000 66 Chapter I A WHERE Clause Is Added to the Statement Notice that the WHERE has excluded rows before the final ordering SELECT empno ename orig_salary FROM employee WHERE orig_salary 43000 ORDER BY orig_salary Gives EMPNO ENAME ORIG_SALARY -06 c--oo 101 John 102 Stephanie 108 David 122 Lindsey 36000 35000 35000 37000 40000 Notice that ORDER BY is applied last after the SELECT . FROM . WHeRE. An Analytical Function Is Added to the Statement Note here that the WHERE is applied before the RANKO. SELECT empno ename orig_salary RANK OVER ORDER BY orig_salary rankorder FROM employee WHERE orig_salary 43000 ORDER BY orig_salary 67 The Analytical Functions in Oracle Analytical Functions I Gives EMPNO ENAME ORIG_SALARY RANKORDER C--o- 0 1 101 John 35000 2 102 Stephanie 35000 2 108 David 37000 4 122 Lindsey 40000 5 A Join Is Added to the Statement What will happen to the order of execution if a join is included in the statement We will add another table to the statement then perform a join and see what happens. Suppose we have a table called Job with this description Name Null Type EMPNO NUMBER 3 JOBTITLE VARCHAR2 20 and this data EMPNO JOBTITLE 101 Chemist 102 Accountant 102 Mediator 111 Musician 122 Director Personnel 122 Mediator 108 Mediator 106 Computer Programmer 104 Head Mediator .
