MYSQL UPDATE SET 在同一列上，但有多个 WHERE 子句

Question

With MYSQL I'm using this query:

UPDATE CustomerDetails_COPY
SET Category_ID = 10
WHERE Category_ID = 2

Thats fine but I'd like to ad 15+ more SET/WHERE to it like:

UPDATE CustomerDetails_COPY
SET Category_ID = 9  WHERE Category_ID = 3
SET Category_ID = 12 WHERE Category_ID = 4
SET Category_ID = 11 WHERE Category_ID = 5
.....

How would I add to this?

EDIT:

As Per Hunters Suggestion:

UPDATE CustomerDetails_COPY
    SET Category_ID = CASE Category_ID
        WHEN 2 THEN 10 
        WHEN 3 THEN 9
        WHEN 4 THEN 12
        WHEN 5 THEN 11
    END
WHERE Category_ID IN (2,3,4,5)

This works Great! Thanks

Answer 1

Something like this should work for you:

UPDATE CustomerDetails_COPY
    SET Category_ID = CASE Category_ID
        WHEN 2 THEN 10 
        WHEN 3 THEN 9
        WHEN 4 THEN 12
        WHEN 5 THEN 11
    END
WHERE Category_ID IN (2,3,4,5)

Alternatively, as Simon suggested, you could do this to save from entering the values twice:

UPDATE CustomerDetails_COPY
    SET Category_ID = CASE Category_ID
        WHEN 2 THEN 10 
        WHEN 3 THEN 9
        WHEN 4 THEN 12
        WHEN 5 THEN 11
        ELSE Category_ID
    END

Source: http://www.karlrixon.co.uk/writing/update-multiple-rows-with-different-values-and-a-single-sql-query/

Answer 2

The typical way to do this would be

UPDATE CustomerDetails_COPY SET Category_ID = 10 WHERE Category_ID = 2
UPDATE CustomerDetails_COPY SET Category_ID = 9  WHERE Category_ID = 3
UPDATE CustomerDetails_COPY SET Category_ID = 12 WHERE Category_ID = 4
UPDATE CustomerDetails_COPY SET Category_ID = 11 WHERE Category_ID = 5

Is there any reason you are avoiding this approach?

Is there any correlation between the new and old values of category_ID?

Answer 3

you could create another table where the mapping is made.. like:

map_table
-----------
mani_id
new_id

then fill it in...

then

UPDATE CustomerDetails_Copy set category_id = (select new_id from map_table where mani_id = category_id )