依次为：======================================================================1、 select BAUTH from BOOK where BNAME = '操作系统' and PNO = (select PNO from PUBLISH where PNAME = '高等教育出版社'); ======================================================================2、 select PTEL from PUBLISH where PNO = (select distinct PNO from BOOK where BAUTH = '张欣' and BTYPE = '小说'); ======================================================================3、 select BPRICE, PNAME, BTYPE from BOOK, PUBLISH where BOOK。
  PNO = PUBLISH。
  PNO and PNAME = '电子工业出版社' and BTYPE = '计算机'; ======================================================================4、 select * from BOOK where BNAME = '高等数学' and BPRICE < (select BPRICE from BOOK where BNAME = '高等数学' and PNO = (select PNO from PUBLISH where PNAME = '人民邮电出出版社')); ======================================================================5、 select BNAME, BAUTH from BOOK where BNAME like '%计算机%'; ======================================================================6、 alter table BOOK add BDATA date ( NULL | NOT NULL ); //--括号里的null是指新增的该字段是否允许接受空值，可接受则写null，不可接受则写not null ======================================================================7、 create index 索引名称 on BOOK (BAUTH); //--因为该表里，同一个作者会出现多次，所以不应建立聚簇索引 ======================================================================。