111. 返回大於等於N的最小整數值? SELECT CEIL(N) FROM DUAL; 112. 返回小於等於N的最小整數值? SELECT FLOOR(N) FROM DUAL; 113. 返回當前月的最後一天? SELECT LAST_DAY(SYSDATE) FROM DUAL; 114. 如何不同用戶間數據導入? IMP SYSTEM/MANAGER FILE=AA.DMP FROMUSER=USER_OLD TOUSER=USER_NEW ROWS=Y INDEXES=Y ;
115. 如何找數據庫表的主鍵字段的名稱? SQL>SELECT * FROM user_constraints WHERE CONSTRAINT_TYPE='P' and table_name='TABLE_NAME'; 116. 兩個結果集互加的函數? SQL>SELECT * FROM BSEMPMS_OLD INTERSECT SELECT * FROM BSEMPMS_NEW; SQL>SELECT * FROM BSEMPMS_OLD UNION SELECT * FROM BSEMPMS_NEW; SQL>SELECT * FROM BSEMPMS_OLD UNION ALL SELECT * FROM BSEMPMS_NEW; 117. 兩個結果集互減的函數? SQL>SELECT * FROM BSEMPMS_OLD MINUS SELECT * FROM BSEMPMS_NEW; 118. 如何配置Sequence? 建sequence seq_custid create sequence seq_custid start 1 incrememt by 1; 建表時: create table cust { cust_id smallint not null, ...} insert 時: insert into table cust values( seq_cust.nextval, ...) 119>.日期的各部分的常用的的寫法 取時間點的年份的寫法:SELECT TO_CHAR(SYSDATE,'YYYY') FROM DUAL; 120>.取時間點的月份的寫法:SELECT TO_CHAR(SYSDATE,'MM') FROM DUAL;
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