Simple SQL Script in W3Schools not working-CodePudding

I am currently learning SQL and using the W3Schools Tryit Editor to play around. I am trying to update a table using a lookup from another table. I looked online and figured out the following code to run:

UPDATE OrderDetails
SET OrderDetails.ProductID = Orders.CustomerID
FROM Orders
INNER JOIN OrderDetails
ON OrderDetails.OrderID = Orders.OrderID

But it is coming up with the following error: "Error 1: could not prepare statement (1 near ".": syntax error)"

Is there a problem with my code or are there things that W3Schools doesn't want to run?

CodePudding user response：

The update with join syntax is specific for each db

The query you are using is valid for SQLSERVER

UPDATE OrderDetails
SET OrderDetails.ProductID = Orders.CustomerID
FROM Orders
INNER JOIN OrderDetails
ON OrderDetails.OrderID = Orders.OrderID

but not for my MySQL

UPDATE OrderDetails
INNER JOIN OrderDetails
ON OrderDetails.OrderID = Orders.OrderID
SET OrderDetails.ProductID = Orders.CustomerID

CodePudding user response：

This works:

UPDATE OrderDetails
SET ProductID = (SELECT CustomerID FROM Orders WHERE OrderDetails.OrderID = Orders.OrderID)
WHERE OrderID IN (SELECT OrderID FROM Orders);

Is this what you want?