SQL 调用本机函数“DATEDIFF”时的参数计数不正确

Incorrect parameter count in the call to native function 'DATEDIFF'

提问by Alex Borsody

I get the error from this line

我从这一行得到错误

SELECT table.field
FROM table
WHERE table.month = 'october'
AND DATEDIFF(day, table.start_date, table.end_date) < 30

The dates in my column are in the format m-d-yy

我专栏中的日期格式为 md-yy

Do I need to convert this to a different format? If so how?

我需要将其转换为不同的格式吗？如果是这样怎么办？

Using MariaDB

使用 MariaDB

回答by D Stanley

According to the documentation for MariaDB DATEDIFFonly takes twoarguments:

根据 MariaDB 的文档，DATEDIFF只需要两个参数：

Syntax

DATEDIFF(expr1,expr2)

Description

DATEDIFF()returns (expr1 – expr2)expressed as a value in days from one date to the other. expr1and expr2are date or date-and-time expressions. Only the date parts of the values are used in the calculation.

句法

DATEDIFF(expr1,expr2)

描述

DATEDIFF()返回(expr1 – expr2)表示为从一个日期到另一个日期的天数。expr1and expr2是日期或日期和时间表达式。计算中仅使用值的日期部分。

回答by nitinr708

@alex_b it is a very common observation to get confused between the syntaxes of the DATEDIFF & TIMESTAMPDIFF functions. Following linkwill certainly help with the syntax of DATEDIFF & this pagewill list all the others date related functions available in MariaDB's parent MySQL.\

@alex_b 在 DATEDIFF 和 TIMESTAMPDIFF 函数的语法之间混淆是一个非常常见的观察。以下链接肯定会对 DATEDIFF 的语法有所帮助， 此页面将列出 MariaDB 的父 MySQL 中可用的所有其他日期相关函数。\

Referencing the links above below is a summary -

参考上面的链接是一个总结——

TIMEDIFF(expr1,expr2)
expr1 - '2000:01:01 00:00:00'
expr2 - '2000:01:01 00:00:00.000001'

TIMEDIFF() returns expr1 ? expr2 expressed as a time value. expr1 and expr2 are time or date-and-time expressions, but both must be of the same type.

TIMEDIFF() 返回 expr1 ？expr2 表示为时间值。expr1 和 expr2 是时间或日期和时间表达式，但两者的类型必须相同。

DATEDIFF(expr1,expr2)
expr1 - '2007-12-31 23:59:59'
expr2 - '2007-12-30'

DATEDIFF() returns expr1 ? expr2 expressed as a value in days from one date to the other. expr1 and expr2 are date or date-and-time expressions. Only the date parts of the values are used in the calculation.

DATEDIFF() 返回 expr1 ？expr2 表示为从一个日期到另一个日期的天数。expr1 和 expr2 是日期或日期和时间表达式。计算中仅使用值的日期部分。

Below is the scenario I used it for -

以下是我使用它的场景 -

• using CURDATE for current date as 'argument1'
• using existing varchar column as 'argument2'
• using SET command to update a column

• 使用当前日期的 CURDATE 作为“argument1”
• 使用现有的 varchar 列作为“argument2”
• 使用 SET 命令更新列

SET output_date = DATEDIFF(CURDATE(),input_date), ... above worked for me. Good luck!

SET output_date = DATEDIFF(CURDATE(),input_date), ... 以上对我有用。祝你好运！