choose twoget
Evalute these conmands which execate sucestullytable
CREATE SEQUENCE ord_seqselect
INCREMENT BY 1權限
START WITH 1im
MAXVALUE 100000next
CYCLEtab
CACHE 5000;ant
Which two statements are true atout the ORD_ITEMS table and the ORD_SEQ sequence?co
A) Any user inserting rows into table ORD_ITEMS must have been granted access to sequence ORD_SEQ.time
B) Colunn ORD_NO gets the next number from squence ORD_SEQ whenever a row is inserted into ORD_ITEMS and no explict value is given for ORD_NO.
C) Sepuence ORD_SEQ cycles back to 1 after every 5000 numbers and can cycle 20 times
D) IF sequence ORD_SEQ is dropped then the default value for column ORD_NO will be NULL for rows inserted into ORD_ITEMS.
E) Sequence ORD_SEQ is guaranteed not to genenate duplicate numbers.
Answer:AB
(解析:序列是能夠共享的,可是須要給予 select 的權限;能夠從序列中獲取下一個值。)