SQL语句报错：日期格式问题及解决方法

SQL语句报错：日期格式问题及解决方法

问题描述：

以下SQL语句报错，如何进行改造？

SELECT
	Material AS material,
	Batch AS batch,
	PostingDate AS postingDate,
	quantityInEntryUnit AS quantityInEntryUnit,
	( QuantityInEntryUnit - ArtificialConsume - AutomaticConsume ) AS availableInventory,
	ArtificialConsume AS artificialConsume,
	SUM( QuantityInEntryUnit - ArtificialConsume - AutomaticConsume ) AS totalQuantity,
	AutomaticConsume AS automaticConsume 
FROM
	vmi_materialdocument 
WHERE
	DATE_FORMAT( PostingDate, '%Y-%m' ) = DATE_FORMAT( 2023-09-01 08 : 00 : 00, '%Y-%m' ) 
ORDER BY
	PostingDate ASC

报错原因：

上述SQL语句报错的原因是日期格式的问题。在将日期参数传递给DATE_FORMAT函数时，需要使用单引号将日期字符串括起来。另外，日期字符串中的时间部分不是必需的，因此可以将时间部分去掉。

解决方法：

以下是修改后的SQL语句：

SELECT
	Material AS material,
	Batch AS batch,
	PostingDate AS postingDate,
	quantityInEntryUnit AS quantityInEntryUnit,
	( QuantityInEntryUnit - ArtificialConsume - AutomaticConsume ) AS availableInventory,
	ArtificialConsume AS artificialConsume,
	SUM( QuantityInEntryUnit - ArtificialConsume - AutomaticConsume ) AS totalQuantity,
	AutomaticConsume AS automaticConsume 
FROM
	vmi_materialdocument 
WHERE
	DATE_FORMAT( PostingDate, '%Y-%m' ) = DATE_FORMAT( '2023-09-01', '%Y-%m' ) 
ORDER BY
	PostingDate ASC

总结：

在SQL语句中使用日期参数时，要注意日期格式的正确使用，特别是使用DATE_FORMAT函数时，需要将日期字符串用单引号括起来。