Ðàçðàáîòêà áàç äàííûõ â Delphi. 11 Óðîêîâ


         

 äàííîì çàïðîñå âñå ñîòðóäíèêè


Phil            Forest         Quality Assurance

...

 äàííîì çàïðîñå âñå ñîòðóäíèêè îêàçàëèñü ðàñïðåäåëåíû ïî îòäåëàì, èíà÷å íàçâàíèÿ îòäåëîâ çàìåñòèëèñü áû çíà÷åíèåì null.

À âîò ïðèìåð ïðàâîãî ñîåäèíåíèÿ:

SELECT first_name, last_name, department

FROM employee e RIGHT JOIN department d

  ON e.dept_no = d.dept_no
                         ïîëó÷èòü ñïèñîê ñîòðóäíèêîâ
                                                                     è íàçâàíèå èõ îòäåëîâ,
                                                                     âêëþ÷àÿ îòäåëû, â êîòîðûå åùå
                                                                     íå íàçíà÷åíû ñîòðóäíèêè

FIRST_NAME      LAST_NAME     DEPARTMENT               

=============== ============= =========================

Terri           Lee           Corporate Headquarters   

Oliver H.       Bender        Corporate Headquarters   

Mary S.         MacDonald     Sales and Marketing      

Michael         Yanowski      Sales and Marketing      

Robert          Nelson        Engineering               

Kelly           Brown         Engineering              

Stewart         Hall          Finance                  

Walter          Steadman      Finance                  

Leslie          Johnson       Marketing                

Carol           Nordstrom     Marketing                

<null>          <null>        Software Products Div.   

Bruce           Young         Software Development

...

 ðåçóëüòèðóþùèé íàáîð âõîäèò è îòäåë “Software Products Div.” (à òàêæå îòäåë “Field Office: Singapore”, íå ïðåäñòàâëåííûé çäåñü), â êîòîðîì åùå íåò íè îäíîãî ñîòðóäíèêà. 


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