Question

I am creating a MySQL View table, so my code looks something like this so far:

CREATE VIEW `myview`
AS SELECT
    (do some stuff here) AS `Revenue1`,
    (do some more here)  AS `Revenue2`
FROM ...

Now I want to add a column that is the sum of both of those fields, so I tried this:

CREATE VIEW `myview`
AS SELECT
    (do some stuff here) AS `Revenue1`,
    (do some more here)  AS `Revenue2`,
    (`Revenue1` + `Revenue2`) AS `TotalRevenue`
FROM ...

but this resulted in an error saying that the Revenue1 field was unknown. How can I add the two fields and get the result as a new column?

Answer 1

you must repeat the stuff as:

CREATE VIEW `myview`
AS SELECT
    (do some stuff here) AS `Revenue1`,
    (do some more here)  AS `Revenue2`,
    ((do some stuff here) + (do some more here)) AS `TotalRevenue`
FROM ...

or create a second view as:

CREATE VIEW `myview_Two`
AS SELECT
    `Revenue1`,
    `Revenue2`,
    `Revenue1` + `Revenue2` AS `TotalRevenue`
FROM myview