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oracle当行函数日期

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Jun 07, 2016 pm 02:55 PM

oraclefunctiondate

Oracle内部使用数字存储日期: 世纪,年,月,日,小时,分钟,秒。默认的日期显示格式为DD-MON-RR。 --可以只指定年的后两位，允许存储21世纪日期在21世纪中。 --同样，允许存储20世纪的日期在21世纪中。 SELECT last_name, hire_date FROM employees WHERE hir

Oracle内部使用数字存储日期: 世纪,年,月,日,小时,分钟,秒。

默认的日期显示格式为DD-MON-RR。

--可以只指定年的后两位，允许存储21世纪日期在21世纪中。
--同样，允许存储20世纪的日期在21世纪中。

SELECT last_name, hire_date
FROM employees
WHERE hire_date

oracle当行函数日期三联

SELECT last_name, (SYSDATE-hire_date)/7 AS WEEKS
FROM employees
WHERE department_id = 90;

Statement

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