Oracle常遇问题解析26

会计考友

116. 两个结果集互加的函数?  
sql>select * from bsempms_old intersect select * from bsempms_new;  
! o7 E! R1 O1 w7 @: c! |0 A. zsql>select * from bsempms_old union select * from bsempms_new;  
sql>select * from bsempms_old union all select * from bsempms_new;  
  
117. 两个结果集互减的函数?  
sql>select * from bsempms_old minus select * from bsempms_new;  
  
, a- A7 D  [5 ^4 J118. 如何配置sequence?  
建sequence seq_custid  
create sequence seq_custid start 1 incrememt by 1;  
" j, _6 H0 r/ _# P建表时:  
7 k0 n! L2 b0 r5 L: {create table cust  
/ @, T! o! A! ~3 I{ cust_id smallint not null,  
/ B; G/ I% s5 Z, E9 m$ F$ H% c1 w1 l/ n...}  
insert 时:  
) T- c1 g. C% m( W2 ^4 ~$ Qinsert into table cust  
* W4 i9 U+ }+ j3 t0 |1 e( b4 vvalues( seq_cust.nextval, ...)  
  
1 |, O- M2 Z' ~( v日期的各部分的常用的的写法  
/ H) w: A% T" U119>.取时间点的年份的写法:  
select to_char(sys2003-10-17,’yyyy’) from dual;  
  
120>.取时间点的月份的写法:  
) c) ?. N# j5 zselect to_char(sys2003-10-17,’mm’) from dual;