【正文】
ISTINCT PNO FROM SPJ,S WHERE = AND CITY=39。 )(6) SELECT JNAME FROM SPJ, S, JWHERE = AND = AND =39。 WHERE COLOR=39。視圖本身不獨立存儲在數(shù)據(jù)庫中,是一個虛表。CREATE VIEW VSP AS SELECT SNO, PNO, QTY FROM SPJ,J WHERE = AND =39。第四章6 授權(quán):(1) Grant all privilegesOn 學(xué)生, 班級To U1With grant option(2) Grant select, update(家庭住址)On 學(xué)生To U2(3) Grant selectOn 班級 To public回收授權(quán):(4) revoke all privilegesOn 學(xué)生, 班級from U1cascade(5) revoke select, update(家庭住址)On 學(xué)生from U2(6) revoke selectOn 班級 from public授權(quán):(1) grant select On 職工, 部門 To 王明(2) grant insert, delete On 職工, 部門 To 李勇(4) grant select, update(工資) On 職工 To 劉星(6) grant all privileges On 職工, 部門 To 周平 With grant option回收授權(quán):(1) revoke select On 職工, 部門 from 王明(2) revoke insert, delete On 職工, 部門 from 李勇(4) revoke select, update(工資) On 職工 from 劉星(6) revoke all privileges On 職工, 部門 from 周平 cascade