01-03 Oracle数据库开发技术之简单查询、限制和排序语句（BOBO）（完成）

-课程大纲【课程介绍】本课程全面介绍oracle的SQL语言。介绍查询语句DML语句DDL语句数据库对象等等。【课程目标】数据库SQL语句是JavaEE项目开发的基础。在关系型数据库当中，SQL语句是必备的基础性知识。【课程计划】全面掌握oracle数据库sql语言。EMFN0ENAJffiJOBMGRHIREDATEISALCOMMDEPTNO►17499ALLEHSALESMAN76981981/2/20▼1600.00300.003027521WARDSALESMAN76981981/2/22▼1250.00500.003037654MARTINSALESMAN76981981/9/28▼1250.001400.003047844TURNERSALESMAN76981981/9/8▼1500.000.0030实例4.13要求查询出10部门中的经理或者是30部门的业务员的信息select*fromempwhere(job='MANAGER'anddeptno=10)or(deptno=30andjob='SALESMAN');EMFNOENAMEJOBMGRHIREDATESALCOMMDEPTNO►17499ALLEHSALESMAN76981981/2/20▼1600.00300.003027521WARDSALESMAN_76981981/2/22▼1250.00500.003037654MARTINSALESMAN76981981/9/28▼1250.001400.003047782CLARKMANAGER二78391981/6/9▼2450.001057844TURNERSALESMAN76981981/9/8▼1500.000.0030实例4.14查询不是办事员的且基本工资大于2000的全部雇员信息select*fromempwherejob!二'CLERK'andsal>2000;EMF1T0ENAMEJOBMGRHIREDATESALCOMMDEPTHO►17566JONESMANAGER78391981/4/2 ▼2975.002027698BLAKEflAHAGER78391981/5/1 ▼2850.003037782CLARKMANAGER78391981/6/9 ▼2450.001047788SCOTTANALYST75661987/4/19▼3000.002057839KINGPRESIDEHT1981/11/17▼5000.001067902FORDANALYST75661981/12/3▼3000.0020范围运算符:BETWEEN…AND…实例4.15使用BETWEEN・・,AND…操作符查询出工资范围在1500-3000(包含1500和3000)的全部雇员信息select*fromempwheresal>=1500andsal<=3000;select*fromempwheresalbetween1500and3000;一闭区间EMFNOENAMEJOBMGRHIREDATE_(SALCOMMDEPTNO►17499ALLENSALESMAN_76981981/2/20▼1600.00300.003027566JONESMANAGER78391981/4/2▼2975.002037698BLAKEFitANAGER78391981/5/1▼2850.003047782CLARKMANAGER78391981/6/9▼2450.001057788SCOTTANALYST75661987/4/19▼3000.002067844TURMERSALESMAN76981981/9/8▼1500.000.003077902FORDANALYST75661981/12/3▼3000.0020实例4.16查询出在1981年雇员的全部雇员信息select*fromempwherehiredate>='01T月-1981'andhiredate<='31T2月-1981';select*fromempwherehiredatebetweenJ01-1月T981'andJ31-12月-1981';EMFNOENAME|JOBMGR|HIREDATE|SALCOMMDEPTNO►|17499ALLENSALESMAN76981981/2/20▼1600.00300.0030i27521WARDSALESMAN76981981/2/22▼1250.00500.0030137566JONESMANAGER78391981/4/2▼2975.002047654MARTINSALESMAN76981981/9/28▼1250.001400.003057698BLAKEMANAGER78391981/5/1▼2850.0030(67782CLARKMANAGER78391981/6/9▼2450.0010177839KINGPRESIDENT1981/11/17▼5000.0010187844TURNERSALESMAN76981981/9/8▼1500.000.0030|97900JAMESCLERK76981981/12/3▼950.0030107902FORDANALYST75661981/12/3▼3000.00204.1.6模糊查询：LIKE和NOTLIKE%:代表任意字符串_：代表任意一个字符实例4,17现在查询出雇员姓名是以S开头的全部雇员信息select*fromempwhereenamelike'S%';EMPN0ENAME(JOB|MGR|HIREDATE |SAL|C0MMDEPTNO」►17369SMITHHclerk79021980/12/17▼800.0020I27788SCOTT1ANALYST75661987/4/19—3000.00| 20实例4.18现在要求查询雇员姓名的第二个字母是M的全部雇员信息select*fromempwhereenamelike' ;EMPN0ENAMEJOBMGRKIREDATE一[sal1commDEPTNOJ►173691SMITHCLERK79021980/12/17▼800,0020实例4.19查询出姓名中任意位置包含字母F的雇员信息select*fromempwhereename1ike'%F%';EMPNO1ENAMEHjob]mgrKIREDATE|SAL COMMDEPTNO►17902FORDANALYST75661981/12/3▼〕3000.00120实例4.20查询雇员姓名长度为6或是超过6个的雇员信息select*fromempwhereenamelike'%';EMPNO|ENAME|job-iMGRHIREDATE(SAL|COMMDEPTNO►17654.MARTIHSALESMAN76981981/9/28▼1250.001400.0030]27844TURNERSALESMAN76981981/9/8I1500.000.0030]37934MILLER_CLERK77821982/1/23二1300.0010实例4,21现在要求查询出雇员基本工资中包含1或是在81年雇佣的全部雇员select*fromempwheresal1ike'/1%'orhiredate1ike;EMPNOENAMEJOB 1MGR|HIREDATE|SAL|COMMDEPTNO►|17499ALLENSALESMAN76981981/2/20▼1600.00300.0030I(27521WARDSALESMAN76981981/2/22▼1250.00500.00301137566JONES由AGER7839[1981/4/2▼2975.00201147654MARTINSALESMAN76981981/9/28▼1250.001400.00301|57698BLAKEMANAGER7839[1981/5/1▼2850.00301i67782CLARKMANAGER78391981/6/9▼2450.00101177839KINGPRESIDENT1981/11/17▼5000.00101J87844TURMERSALESMAN76981981/9/8▼1500.000.0030197876ADAMSCLERK77881987/5/23▼1100.0020实例4.22找出部门10中所有经理(MANAGER),部门20中所有办事员(CLERK),既不是经理又不是办事员但其薪金大于2000的所有员工的详细资料，并且要求这些雇员的姓名之中包含有字母S或字母Koselect*fromempwhere((deptno=10andjob='MANAGER')or(deptno=10andjob='CLERK，)or(job!='MANAGER'andjob!='CLERK'andsal>2000))and(enamelike'96S%'orenamelike'%K%')EMPNO|ENAME|JOB 1MGR|HIREDATE 1SAL|C0MMDEPTNO►17782CLARKMANAGER78391981/6/9 ▼2450.00io]27788SCOTTANALYST75661987/4/19~^|3000.OO]20]37839KINGPRESIDENT1981/11/17▼5000.001 104.1.7判断是否为空:ISNULLsISNOTNULL空：未知的，不确定的。跟o是有区别的。实例4.23查询出所有领取佣金的雇员的信息select*fromempwherecommisnotnull;EMFNOENAMEJOBMGR|HIREDATE|SALCOMMDEPTNO|►17499ALLEN_SALESMAN_76981981/2/20▼1600.00300.003027521WARDSALESMAN76981981/2/22*1250.00500.0030137654MARTINSALESMAN76981981/9/28▼1250.001400.0030147844TURNERSALESMAN76981981/9/8▼1500.000.0030实例4.24查询所有不领取佣金的雇员的信息select*fromempwherecommisnul1;EMFNO|ENAMEJOBMGR|HIREDATESAL|COMMDEPTNO►17369SMITH_CLERK79021980/12/17▼800.0020I27566JOHESMANAGER78391981/4/2 ▼2975.0020137698BLAKEf^ANAGER二78391981/5/1 ▼2850.0030147782CLARKMANAGER78391981/6/9 ▼2450.0010157788SCOTTANALYST75661987/4/19▼3000.0020167839KINGPRESIDEHT1981/11/17▼5000.00101177876ADAMS_CLERK__77881987/5/23▼1100.0020187900JAMESCLERK76981981/12/3▼950.0030197902FORDANALYST二75661981/12/3▼3000700201107934MILLERCLERK_77821982/1/23▼1300.0010实例4.25列出所有的不领取奖金的雇员，而且同时要求这些雇员的基本工资大于2000的全部雇员信息select*fromempwherecommisnullandsal>2000;EMFNOENAMEJOBMGRHIREDATESAL|C0MMDEPTNO±17566JONESMANAGER78391981/4/2▼2975.002027698BLAKEMANAGER78391981/5/1▼2850.003037782CLARKMANAGER78391981/6/9▼2450.001047788SCOTTANALYST75661987/4/19▼3000.002057839KINGPRESIDENT1981/11/17▼5000.001067902FORDANALYST75661981/12/3▼3000.0020实例4.26找出不收取佣金的或收取佣金低于100的员工select*fromempwherecommisnullorcomm<100;EMFNOENAMEJOBMGRHIREDATESAL|COMMDEPTNO_|►117369SMITHCLERK_79021980/12/17▼800.0020]27566JOHESMANAGER_78391981/4/2▼2975.00201|37698BLAKE_MANAGER7839[1981/5/1▼2850.0030Ij47782CLARKMANAGER一78391981/6/9▼2450.0010Ij57788SCOTTAHALYST75661987/4/19▼3000.0020167839KINGPRESIDEHT1981/11/17▼5000.00101j77844TURMERSALESMAN—76981981/9/8▼1500.000.00301j87876ADAMSCLERK77881987/5/23▼1100.0020]J97900JAMESCLERK76981981/12/3▼950.0030]|107902FORDANALYST二—75661981/12/3▼3000.0020117934KILLERCLERK77821982/1/23▼1300.0010实例4.27查询收取佣金的员工从事的工作有哪些selectename,jobfromempwherecommisnotnull;ENAMEJOB |►j1ALLENSALESMAN12WARDSALESMAN13MARTINSALESMAN|4TURNER—SALESMAN太腐败了！列范围查找IN、NOTININ：表示间断，跳跃的实例4.28查询出雇员编号是7369、7788、7566的雇员信息select*fromempwhereempnoin(7369,7788,7566);EMPNO|ENAMETOBMGRHIREDATE〕SALCOMMDEPTHO►17369.SMITHCLERKL79021980/12/17▼800.002027566JOBS1MANAGER_78391981/4/2 ▼2975.0020I37788SCOTTANALYST75661987/4/19▼3000.0020实例4.29查询不领取佣金且工作为分析员和经理的员工信息select*fromempwherecommISNULLand(job二'MANAGER'orjob='ANALYST');select*fromempwherecommISNULLandjobin('MANAGER','ANALYST');EMPNOENAMETOBMGR|HIREDATESAL|COMMDEFTNO±17566JONESMANAGER78391981/4/2▼2975.0020I27698BLAKE_MANAGER78391981/5/1▼2850.0030137782CLARKMANAGER78391981/6/9▼2450.0010147788SCOTTANALYST75661987/4/19B3000.0020I57902FORDANALYST75661981/12/3J3000.0020实例4.30查询除了7369、7788、7566之外的雇员信息select*fromempwhereempnonotin(7369,7788,7566);EMPNOENAMEJOB 1MGR|HIREDATE|SALICCM^DEPTNO►17499ALLENSALESMAN76981981/2/20▼1600.00300.0030127521WARDSALESMAN76981981/2/22▼1250.00500.0030]37654MARTINSALESMAN76981981/9/28▼1250.001400.0030147698BLAKEMANAGER78391981/5/1▼2850.0030157782CLARKMANAGER78391981/6/9▼2450.001067839KINGPRESIDENT1981/11/17▼5000.0010177844TURNERSALESMAN_7698[1981/9/8▼1500.000.0030187876ADAMSCLERK77881987/5/23▼1100.0020197900JAMES_CLERK76981981/12/3▼950.00301107902FORDANALYST75661981/12/3▼3000.00201117934FILLERCLERK77821982/1/23▼1300.0010实例4.31在使用NOIIN操作符中设置NULL设定(什么都不会有)select*fromempwhereempnonotin(7369,7788,7566,null);使用ORDERBY子句进行排序语法SELECT*|{[DISTINCT]列名|表达式[列别名],……)FROM表名称[表别名][WHERE过滤条件⑸][ORDERBY排序的字段1ASC|DESC,排序的字段2ASQDESC,…];实例实例4.32查询雇员的完整信息并且按照基本工资由高到低进行排序select*fromemporderbysaldesc;EMPNOENAME|JOBMGRHIREDATE—|SALCOMMDEPTNO|►117839KING_PRESIDENT1981/11/17▼5000.00io]27902FORDANALYST75661981/12/3▼3000.0020Ij37788SCOTT_ANALYST75661987/4/19▼3000.00201147566JONESMANAGER78391981/4/2▼2975.0020]57698BLAKEMANAGER-78391981/5/1▼2850.00301167782CLARKMANAGER_78391981/6/9▼2450.00101|77499ALLEN_SALESMAN76981981/2/20▼1600.00300.00301|87844TURMERSALESMAN-76981981/9/8▼1500.000.0030]j97934MILLER_CLERK__77821982/1/23▼1300.00101107521WARDSALESMAN76981981/2/22▼1250.00500.0030]117654MARTIN_SALESMAH_76981981/9/28▼1250.001400.00301127876ADAMSCLERK77881987/5/23▼1100.00201137900JAMESCLERK76981981/12/3▼950.00301147369SMITHCLERK79021980/12/17▼800.0020实例4.33查询出所有办事员(CLERK)的信息，并且按照基本工资由低到高排序select*fromempwherejob='CLERK'orderbysalasc;EMPNO|ENAME[JOBMGR|HIREDATESAL|COMMDEPTNO►17369SMITH_CLERKr79021980/12/17▼800.002027900JAMESCLERK76981981/12/3▼950.0030137876ADAMSCLERK-77881987/5/23▼1100.0020147934MILLERCLERK77821982/1/23二1300.0010实例4.34查询出所有雇员信息，要求按照基本工资由高到低排序，如果工资相等则按照雇佣日期进行排序，按照由早到晚的顺序select*fromemporderbysaldesc,hiredateasc;EMPNO|ENAME|JOBMGRHIREDATESAL|COMMDEPTNO►17839KINGPRESIDEHT1981/11/17▼5000.001027902FORDANALYST75661981/12/3▼3000.002037788SCOTT_ANALYSTT75661987/4/19▼3000.0020j47566JONESMANAGER78391981/4/2▼2975.002057698BLAKEMANAGER78391981/5/1▼2850.003067782CLARKMANAGER78391981/6/9▼2450.001077499ALLEN_SALESMAN76981981/2/20▼1600.00300.003087844TURNERSALESMAN76981981/9/8▼1500.000.003097934MILLERCLERK77821982/1/23▼1300.0010107521WARDSALESMAN76981981/2/22▼1250.00500.0030117654MARTINSALESMANT76981981/9/28▼1250.001400.0030127876ADAMSCLERK77881987/5/23▼1100.0020137900JAMESCLERK76981981/12/3▼950.0030147369SMITHCLERK79021980/12/17▼800.0020实例4.35查询雇员的编号、姓名、工资，并按工资升序排序selectempno,ename,salfromemporderby3;EMPNO|ENAMESAL|►j17369SMITH_800.00|27900JAMES950.0037876ADAMS1100.0047521WARD1250.0057654MARTIN1250.00167934KILLER1300.00j77844TURNER1500.0087499ALLEN1600.0097782CLARK2450.00107698BLAKE2850.00117566JONES_2975.00127788SCOTT3000.00137902FORD3000.00147839KING5000.00实例4.36查询雇员的编号、姓名、工资，并按工资别名降序排序selectempno,ename,salassfromemporderbysdesc;EMFNOENAME|s1►j17839KING_5000.0027902FORD3000.0037788SCOTT_3000.00147566JONES2975.00|57698BLAKE2850.0067782CLARK2450.0077499ALLEN_1600.00187844TURNER1500.00|97934HILLER1300.00107521WARD1250.00117654MARTIN1250.00127876ADAMS1100.00137900JAMES950.00147369SMITH800.00第二章：SQL语言简介什么是SQL结构化查询语言（StructuredQueryLanguage）是高级的非过程化编程语言，它不要求用户指定对数据的存取方法，屏蔽了底层的数据的存取过程。好像领导交给任务给下属，下属自主去完成任务，而不是由领导指定下属该怎么做；领导告诉下属自己需要什么，而不是领导告诉下属怎么样去执行。发展历史1986年10月，美国国家标准协会发布SQL规范，作为关系式数据库管理系统的标准语言。1987年得到国际标准化组织的支持下成为国际标准。各种数据库生产对现有的SQL规范进行扩充，以满足自己数据库产品的需要。FoxBase（Dos下运行）、FoxPro（Windows3.1/3.2/98）SQLServer、MySQL、Oracle等。数据查询语言数据操纵语言数据定义语言事务控制语言数据控制语言2.3SQL分类数据查询语言数据操纵语言数据定义语言事务控制语言数据控制语言（查询）（增删改）（定义、修改删除数据库对象）（组合增删改操作形成事务，事务有提交、回滚、保存点和状态）（授权和回收）第三章：简单查询语句3.1语法SELECT［DISTINCT］*|列名称［AS］［列别名］,列名称［AS］［列别名］,FROM表名称［表别名］;3.2实例实例3.1查询scott用户的表select*fromtab;THAMETABTYPECLUSTERID►11BONUS…TABLE_12DEPT …TABLE|3EMPTABLE4SALGRADE…TABLE实例3.2查询emp表中的全部数据select*fromemp;select*fromdept;select*fromsalgrade;员工编号员工名字工作上级领导员工编号入职时间工资奖金部门编号EMPNOENAMEJOBMGRHIREDATESALCOMMDEPTNO►17369SMITHCLERK79021980/12/17▼800.002027499ALLENSALESMAN76981981/2/20▼1600.00300.003037521WARDSALESMAN76981981/2/22▼1250.00500.003047566JONESMANAGER78391981/4/2▼2975.002057654fitARTINSALESMAN76981981/9/28▼1250.001400.0030167698BLAKEMANAGER78391981/5/1▼2850.003077782CLARKMANAGER78391981/6/9▼2450.001087788SCOTTANALYST75661987/4/19▼3000.002097839KINGPRESIDENT1981/11/17▼5000.0010107844TURNERSALESMAN76981981/9/8▼1500.000.0030117876ADAMSCLERK77881987/5/23▼1100.0020127900JAMESCLERK76981981/12/3▼950.0030137902FORDANALYST75661981/12/3▼3000.00201147934MILLERCLERK77821982/1/23▼1300.0010部门编号部门名称位置DEPTNODNAMELOC |►|110ACCOUNTINGNEWYORK|220RESEARCHDALLAS一330SALESCMICAGOj440OPERATIONSBOSTON等级下限上限GRADED3SALHISAL►1170012002212011400331401200044200130005530019999实例3.3查询公司每个雇员的编号、姓名、工资三个信息进行selectempno,ename,salfromemp;EMPN0ENAMESAL►17369SJidTH800.00J27499ALLEN1600.0037521WARD1250.0047566JONES2975.0057654MARTIN1250.0067698BLAKE2850.0077782CLARK2450.0087788SCOTT3000.0097839KING5000.00107844TURNER1500.00117876ADAMS1100.00127900JAMES950.00137902FORD3000.00147934MILLER1300.00实例3.4查询公司中所有雇员的职位信息select*fromemp;selectjobfromemp;实例3.5显示公司所有职位名称（去掉重复）selectdistinctjobfromemp;□IJDB |回ERKJ2SALESMANJ3PRESIDEHldJ4MANAGER|15ANALYST实例3.6查询出所有雇员的编号、雇员姓名和年基本工资、日基本工资selectempno,ename,sal*12,sal/30Promemp;EMPNOENAMESAL*12 1SAL/30►17369SMITH960026.666666666666727499ALLEN1920053.333333333333337521WARD1500041.666666666666747566JONES3570057654MARTIN1500041.666666666666767698BLAKE342009577782CLARK2940081.666666666666787788SCOTT3600010097839KING60000166.666666666667107844TURNER1800050117876ADAMS1320036.6666666666667127900JAMES1140031.6666666666667137902FORD36000100147934MILLER1560043.3333333333333实例3.7年底增加5000元奖金，计算年工资selectempno,ename,saH12+5000fromemp;EMPNOENAME1SAL*12-♦5000►17369SMITH1460027499ALLEN2420037521WARD2000047566JUNES4070057654MARTIN2000067698BLAKE3920077782CLARK3440087788SCOTT4100097839KING65000107844TURNER23000117876ADAMAMES16400137902FORD41000147934MILLER20600实例3.8每月工资增加200元，计算年工资selectempno,ename,(sal+200)*12fromemp;EMPNO|ENAME(SAL+200)*12►117369SMITH12000|27499ALLEN216001I37521WARD174001j47566JONES381001f57654MARTIH174001I67698BLAKE366001177782CLARK318001j87788SCOTT384001197839KING6240011107844TURNER204001117876ADAMS156001127900JAMES138001137902FORD384001147934HILLER18000年工资fromemp;as年工资fromemp;as“年工资〃fromemp;实例3.9年工资fromemp;as年工资fromemp;as“年工资〃fromemp;EMPNOENAME1年工资►j17369SMITH1200027499一ALLEN2160037521WARD_1740047566JONES3810057654KARTILAKE36600177782CLARK_3180087788SCOTT3840097839KING_| 62400107844TURNER20400117876ADAMSAMEORD38400147934HILLER18000实例3.10使用“II”进行连接selectename'的年工资是：'||sal*12as员工年工资fromemp;selectenamel|'''ssalaryis:'||sal*12as员工年工资fromemp;员工年工^►1SMITH的年工资是：96002M10庄）年工资是：192003WARD的舁工资是：150004JONES的年工资是：357005MART工N的年工资是：15000…6BLAKE的舁工资是：342007CLARK的本工资是：294008SCOTT的舁工资是：36000…9KI崎舁工资是：60000TURNER的年工资是：18000…101112ADAMS的舁工资是：1320。JAMES的辛工资是：1140013FORD的年工资是：36000MILLER的年工资是：15600…14实例3.11SQL不区分大小写select*fromemp;SELECT*FROMEMP;第四章：限制和排序语句限制查询如果要查询所有成千上万的记录的话，有可能耗尽内存。语法SELECT*|｛［DISTINCT］列名|表达式［列别名］,……)FROM表名称［表别名］类别关系运算符判断是否为空逻辑运算符范围查询列表范围查询模糊查询［WHERE过滤条件⑸］类别关系运算符判断是否为空逻辑运算符范围查询列表范围查询模糊查询符号＞、＜、〉二、＜二、二、！二、＜＞ISNULL.ISNOTNULLAND、OR、NOTBETWEEN-AND-INLIKE关系运算符：=实例4.1查询10部门的员工select*fromempwheredeptno=10;一字段名运算符值EMPN0|ENAME|IJOB 1MGR|HIREDATE 1SAL|COMMDEPTNO117782CLARKMANAGER78391981/6/9 ▼2450.0010|27839KINGPRESIDENT1981/11/17▼5000.00I1037934MILLERCLERK77821982/1/23,1300.0010实例4.2查询姓名为KING的信息select*fromempwhereename='KING';--字符串常量是大小写区分的EMPNO-jENAMEJOB |MGRHIREDATESALjCOMMDEPTNO►17839KINGPRESIDENT1981/11/17▼5000JO10实例4.3查询工资为3000的员工信息select*fromempwheresal=3000;EMPNOENAMEIJOB|mgrHIREDATE|SAL|COMM|DEPTNO|►17788SCOTTANALYSTI75661987/4/19▼3000.002027902FORD_|ANALYST75661981/12/3▼3000.00 20实例4.4查询1981年12月3日进入公司员工信息select*fromempwherehiredate='03T2月-1981';一日上补0月上不补0EMPNOENAME|JDB|mgrHIREDATE|SALICOMMDEPTNO►17900JAMES二（clerk176981981/12/3950.003027902FORD1ANALYST75661981/12/3▼3000.0020品毋淘口.新t对话框编辑器ConnectedtoOracleDatabase11gEnterpriseEditionReieasConnectedasscottSBEDUSQL〉descemp;Name Type NullableDefaultCommentsEMPNO NUMBER（4）ENAME VARCMAR2（10） YJOB VARCHAR2（9） YMGR HUMBER（4） YHIREDATEDATE YSAL NIIMBERE2） YCOMM NUMBER（7.2） YDEPTNO NUMBER（2） YSQL>4.L3关系运算符：＞、V、＞=、＜=、！=、＜＞实例4.5查询工资高于1300的员工信息select*fromempwheresal>1300;EMPNOENAME|JOB MGRHIREDATE |SALCOMMDEPTNO117499ALLENSALESMAN76981981/2/20▼1600.00300.0030I|27566JONESMANAGER78391981/4/2 ▼2975.00201137698BLAKE_MANAGER78391981/5/1 ▼2850.0030147782CLARKMANAGER78391981/6/9 ▼2450.0010]57788SCOTTANALYST_一75661987/4/19▼3000.0020167839KINGPRESIDENT1981/11/17▼5000.00101|77844TURNERSALESMAN76981981/9/8 ▼1500.000.0030j87902FORDANALYST75661981/12/3▼3000.0020实例4.6查询工资低于或等于1500的全部雇员信息select*fromempwheresal<=1500;EMPNOENAMEJOBMGRHIREDATEIsALCOMMDEPTNO►17369SMITHCLERK79021980/12/17▼800.0020127521WARDSALESMAN_76981981/2/22▼1250.00500.003037654MARTINSALESMAN76981981/9/28▼1250.001400.003047844TURNERSALESMAN76981981/9/8▼1500.000.003057876ADAMS_CLERK_77881987/5/23▼1100.002067900JAMES一CLERK-76981981/12/3▼950.003077934MILLERCLERK77821982/1/23▼1300.0010实例4.7查询出所有基本工资大于等于2000的全部雇员信息select*fromempwheresal＞=2000;EMFN0ENAMEJOBMGRHIREDATESALCOMMDEPTNO►117566JONESMANAGER78391981/4/2 ▼2975.0020276