Ðàçðàáîòêà áàç äàííûõ â Delphi. 11 Óðîêîâ
BETWEEN
Ïðåäèêàò BETWEEN çàäàåò äèàïàçîí çíà÷åíèé, äëÿ êîòîðîãî âûðàæåíèå ïðèíèìàåò çíà÷åíèå true. Ðàçðåøåíî òàêæå èñïîëüçîâàòü êîíñòðóêöèþ NOT BETWEEN.
SELECT first_name, last_name, salary
FROM employee
WHERE salary BETWEEN 20000 AND 30000
ïîëó÷èòü ñïèñîê ñîòðóäíèêîâ,
ãîäîâàÿ çàðïëàòà êîòîðûõ
áîëüøå 20000 è ìåíüøå 30000
FIRST_NAME LAST_NAME SALARY
=============== ========== ===============
Ann Bennet 22935.00
Kelly Brown 27000.00
Òîò æå çàïðîñ ñ èñïîëüçîâàíèåì îïåðàòîðîâ ñðàâíåíèÿ áóäåò âûãëÿäåòü ñëåäóþùèì îáðàçîì:
SELECT first_name, last_name, salary
FROM employee
WHERE salary >= 20000
AND salary <= 30000 ïîëó÷èòü ñïèñîê ñîòðóäíèêîâ,
ãîäîâàÿ çàðïëàòà êîòîðûõ
áîëüøå 20000 è ìåíüøå 30000
FIRST_NAME LAST_NAME SALARY
=============== ========== ===============
Ann Bennet 22935.00
Kelly Brown 27000.00
Çàïðîñ ñ ïðåäèêàòîì BETWEEN ìîæåò èìåòü ñëåäóþùèé âèä:
SELECT first_name, last_name, salary
FROM employee
WHERE last_name BETWEEN "Nelson" AND "Osborne"
ïîëó÷èòü ñïèñîê ñîòðóäíèêîâ,
ôàìèëèè êîòîðûõ íà÷èíàþòñÿ
ñ “Nelson”
è çàêàí÷èâàþòñÿ “Osborne”
FIRST_NAME LAST_NAME SALARY
=============== =============== ================
Robert Nelson 105900.00
Carol Nordstrom 42742.50
