Oracle OCP 19c 认证1Z0-082考试题库(第24题)-CUUG内部学员版082题库解析
24、Evaluate these commands which execute successfully:CREATE SEQUENCE ord_seqINCREMENT BY 1START WITH 1MAXVALUE 100000CYCLECACHE 5000;CREATE TABLE ord_items(ord_no NUMBER(4) DEFAULT ord_seq.NEXTVALUE NOT NULL,item_no NUMBER(3),qty NUMBER(3),expiry_date DATE,CONSTRAINT it_pk PRIMARY KEY(ord_no,item_no),CONSTRAINIT ord_fk FOREIGN KEY(ord_no) REFERENCES orders (ord_no));Which two statements are true about the ORD_ITEMS table and the ORD_SEQ sequence? (Choose two.)A. If sequence ORD_SEQ is dropped then the default value for column ORD_NO will be NULL for rows inserted into ORD_ITEMSB. Any user inserting rows into table ORD_ITEMS must have been granted access to sequence ORD_SEQC. Column ORD_NO gets the next number from sequence ORD_SEQ whenever a row is inserted into ORD_ITEMS and no explicit value is given for ORD_NOD. Sequence ORD_SEQ cycles back to 1 after every 5000 numbers and can cycle 20 timesE. Sequence ORD_SEQ is guaranteed not to generate duplicate numbers
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