c# - 我有一个 varchar 字段日期，我想将其视为日期时间，因此我可以将其与 now()

Question

update borrowdetails 
set LM_Status = 'BORROWED' 
where LM_Status = 'D' and Borrow_DueDate <= now()

Borrow_DueDate是Duedate列，但它是一个varchar，我想把它当作日期时间..

Answer 1

update borrowdetails 
set LM_Status = 'BORROWED' 
where LM_Status = 'D' and str_to_date(Borrow_DueDate,'%Y-%m-%d') <= now()

这会将您的列转换为日期

UPDATE `borrowdetails `
SET `Borrow_DueDate` = str_to_date( `Borrow_DueDate`, '%Y-%m-%d' )