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返回两日期天数

  • 2020-04-23 04:02
  • 数据库知识
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sql 日期相减DATEDIFF(State of Qatar重临两天期天数

概念和用法DATEDIFF(卡塔尔国 函数重返五个日子之间的气数。

语法DATEDIFF(date1,date2卡塔尔(قطر‎date1 和 date2 参数是官方的日子或日期/时间表达式。

讲明:只有值的日子部分出席总结。

DATEDIFF(expr1,expr2): returns expr1 - expr2 as a value in days

实例一

SELECT DATEDIFF('2008-12-30','2008-12-29') AS DiffDate

mysql教程mysql SELECT DATEDIFF('1997-12-31 23:59:59','1997-12-30');+----------------------------------------------+| DATEDIFF('1997-12-31 23:59:59','1997-12-30') |+----------------------------------------------+| 1 |+----------------------------------------------+1 row in set (0.00 sec)

mysqlmysql SELECT DATEDIFF('1997-11-30 23:59:59','1997-12-31');+----------------------------------------------+| DATEDIFF('1997-11-30 23:59:59','1997-12-31') |+----------------------------------------------+| -31 |+----------------------------------------------+1 row in set (0.00 sec)

研究两字段时期的日期

mysql CREATE TABLE Employee( - id int, - first_name VARCHAR(15), - last_name VARCHAR(15), - start_date DATE, - end_date DATE, - salary FLOAT(8,2), - city VARCHAR(10), - description VARCHAR(15) - );Query OK, 0 rows affected (0.03 sec)

mysqlmysqlmysql insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) - values (1,'Jason', 'Martin', '19960725', '20060725', 1234.56, 'Toronto', 'Programmer');Query OK, 1 row affected (0.00 sec)

mysqlmysql insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) - values(2,'Alison', 'Mathews', '19760321', '19860221', 6661.78, 'Vancouver','Tester');Query OK, 1 row affected (0.00 sec)

mysqlmysql insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) - values(3,'James', 'Smith', '19781212', '19900315', 6544.78, 'Vancouver','Tester');Query OK, 1 row affected (0.00 sec)

mysqlmysql insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) - values(4,'Celia', 'Rice', '19821024', '19990421', 2344.78, 'Vancouver','Manager');Query OK, 1 row affected (0.00 sec)

mysqlmysql insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) - values(5,'Robert', 'Black', '19840115', '19980808', 2334.78, 'Vancouver','Tester');Query OK, 1 row affected (0.00 sec)

mysqlmysql insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) - values(6,'Linda', 'Green', '19870730', '19960104', 4322.78,'New York', 'Tester');Query OK, 1 row affected (0.00 sec)

mysqlmysql insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) - values(7,'David', 'Larry', '19901231', '19980212', 7897.78,'New York', 'Manager');Query OK, 1 row affected (0.00 sec)

mysqlmysql insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) - values(8,'James', 'Cat', '19960917', '20020415', 1232.78,'Vancouver', 'Tester');Query OK, 1 row affected (0.00 sec)

mysqlmysql select * from Employee;+------+------------+-----------+------------+------------+---------+-----------+-------------+| id | first_name | last_name | start_date | end_date | salary | city | description |+------+------------+-----------+------------+------------+---------+-----------+-------------+| 1 | Jason | Martin | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto | Programmer || 2 | Alison | Mathews | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester || 3 | James | Smith | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester || 4 | Celia | Rice | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager || 5 | Robert | Black | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester || 6 | Linda | Green | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester || 7 | David | Larry | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager || 8 | James | Cat | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester |+------+------------+-----------+------------+------------+---------+-----------+-------------+8 rows in set (0.00 sec)

mysqlmysqlmysqlmysql SELECT * - FROM employee - WHERE (DATEDIFF(curdate(),start_date)/365.25) 55;Empty set (0.00 sec)