oracle ³£Óú¯Êý

1. select * from emp;
2. select empno, ename, job from emp;
3. select empno ±àºÅ, ename ÐÕÃû, job ¹¤×÷ from emp;
4. select job from emp;
5. select distinct job from emp;
6. select distinct empno, job from emp;
˵Ã÷:ÒòΪ¹ÍÔ±±àºÅ²»Öظ´, ËùÒÔ´Ëʱ֤Ã÷ËùÓеÄÁÐûÓÐÖظ´,ËùÒÔ²»ÄÜÏû³ýµôÖظ´µÄÁÐ.
7. ²éѯ³ö¹ÍÔ±µÄ±àºÅ, ÐÕÃû, ¹¤×÷, µ«ÊÇÏÔʾµÄ¸ñʽ:±àºÅÊÇ: 7369 µÄ¹ÍÔ±, ÐÕÃûÊÇ: smith, ¹¤×÷ÊÇ: clear
select '±àºÅÊÇ: ' || empno || 'µÄ¹ÍÔ±, ÐÕÃûÊÇ: ' || ename || ', ¹¤×÷ÊÇ: ' || job from emp;
8. Çó³öÿ¸ö¹ÍÔ±µÄÐÕÃû¼°Äêн
select ename, sal * 12 income from emp;
9. Çó³ö¹¤×Ê´óÓÚ 1500 µÄËùÓйÍÔ±ÐÅÏ¢
select * from emp where sal > 1500;
10. ²éѯÿÔ¿ÉÒԵõ½½±½ðµÄ¹ÍÔ±ÐÅÏ¢
select * from emp where comm is not null;
11. ²éѯûÓн±½ðµÄ¹ÍÔ±ÐÅÏ¢
select * from emp where comm is null;
12. ²éѯ³ö»ù±¾¹¤×Ê´óÓÚ 1500 ͬʱ¿ÉÒÔÁìÈ¡½±½ðµÄ¹ÍÔ±ÐÅÏ¢
select * from emp where sal > 1500 and comm is not null;
13. ²éѯ³ö»ù±¾¹¤×Ê´óÓÚ 1500 »òÕß¿ÉÒÔÁìÈ¡½±½ðµÄ¹ÍÔ±ÐÅÏ¢
select * from emp where sal > 1500 or comm is not null;
14. ²éѯ³ö»ù±¾¹¤×ʲ»´óÓÚ 1500 »òÕß²»¿ÉÒÔÁìÈ¡½±½ðµÄ¹ÍÔ±ÐÅÏ¢
select * from emp where not(sal > 1500 and comm is not null);
15. ²éѯ»ù±¾¹¤×Ê´óÓÚ 1500, µ«ÊÇСÓÚ 3000 µÄÈ«²¿¹ÍÔ±ÐÅÏ¢
select * from emp where sal > 1500 and sal < 3000;
16. ²éѯ»ù±¾¹¤×Ê´óÓÚµÈÓÚ 1500, µ«ÊÇСÓÚµÈÓÚ 3000 µÄÈ«²¿¹ÍÔ±ÐÅÏ¢
select * from emp where sal >= 1500 and sal <= 3000;
select * from emp where sal between 1500 and 3000;
17. ²éѯ³öÔÚ 1981 Äê¹ÍÓ¶µÄÈ«²¿¹ÍÔ±ÐÅÏ¢(1981 Äê 1 Ô 1 ÈÕ µ½ 1981 Äê 12 Ô 31 ÈÕÖ®¼äµÄ¹ÍÓ¶µÄ¹ÍÔ±)
select * from emp where hiredate between '1-1ÔÂ-81' and '31-12ÔÂ-81';
18. ÒªÇó²éѯ³öÐÕÃûÊÇ smith µÄ¹ÍÔ±ÐÅÏ¢
select * from emp where ename = 'SMITH';
19. ÒªÇó²éѯ³ö¹ÍÔ±ÊÇ 7369, 7499, 7521 µÄ¹ÍÔ±µÄ¾ßÌåÐÅÏ¢
select * from emp where empno = 7369 or empno = 7499 or empno = 7521;
select * from emp where empno in(7369, 7499, 7521);
20. ÒªÇó²éѯ³ö¹ÍÔ±²»ÊÇ 7369, 7499, 7521 µÄ¹ÍÔ±µÄ¾ßÌåÐÅÏ¢
select * from emp where empno not in(7369, 7499, 7521);