SELECT语句 - 添加另一个派生字段

Question

我有一个有3列的表。 Name，DateOfBirth，DateDeceded。字段DateOfBirth和DateDeceded的数据类型为DATE。

现在当我做Select * from TableName时。我想显示姓名，出生日期，被除名的日期以及该人居住的年数（DateDeceded - DateOfBirth）。

如何编写SQL Select语句以包含NumberOfYearsLived字段？

Answer 1

尝试：

SELECT Name,
       DateOfBirth,
       DateDeceded,
       YEAR(DateDeceded) - YEAR(DateOfBirth) AS NumberOfYearsLived
  FROM TableName

编辑：你可能想尝试这个。它可能更准确。

SELECT Name,
       DateOfBirth,
       DateDeceded,
       TIMESTAMPDIFF(YEAR, DateDeceded, DateofBirth) AS NumberOfYearsLived
  FROM TableName

http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_timestampdiff