取周的開始时间。以星期一为開始。
SQL>SELECT TRUNC(TO_DATE(‘2013-11-25 10:31:11‘,‘YYYY-MM-DD HH24:MI:SS‘),‘D‘) + 1 ASA FROM DUAL;
A
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2013/11/25
取周的结束时间。以星期日为结束
SQL>SELECT TRUNC(TO_DATE(‘2013-11-25 10:31:11‘,‘YYYY-MM-DD HH24:MI:SS‘),‘D‘) + 7 ASA FROM DUAL;
A
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2013/12/1
取月的開始时间
SQL>SELECT TRUNC(TO_DATE(‘2013-11-25 10:31:11‘,‘YYYY-MM-DD HH24:MI:SS‘),‘MM‘) AS AFROM DUAL;
A
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2013/11/1
取月的结束时间
SQL>SELECT LAST_DAY(TO_DATE(‘2013-11-25 10:31:11‘,‘YYYY-MM-DD HH24:MI:SS‘)) AS AFROM DUAL;
A
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2013/11/30
取季的開始时间
SQL>SELECT TRUNC(TO_DATE(‘2013-11-25 10:31:11‘,‘YYYY-MM-DD HH24:MI:SS‘),‘Q‘) AS AFROM DUAL;
A
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2013/10/1
取季的结束时间
SQL>SELECT ADD_MONTHS(TRUNC(TO_DATE(‘2013-11-25 10:31:11‘,‘YYYY-MM-DDHH24:MI:SS‘),‘Q‘),3)-1 AS A FROM DUAL;
A
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2013/12/31
取年的開始时间
SQL>SELECT TRUNC(TO_DATE(‘2013-11-25 10:31:11‘,‘YYYY-MM-DD HH24:MI:SS‘),‘YYYY‘) ASA FROM DUAL;
A
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2013/1/1
取年的结束时间
SQL>SELECT ADD_MONTHS(TRUNC(TO_DATE(‘2013-11-25 10:31:11‘,‘YYYY-MM-DDHH24:MI:SS‘),‘YYYY‘),12)-1 AS A FROM DUAL;
A
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2013/12/31
原文:http://www.cnblogs.com/yutingliuyl/p/7162630.html