Which is faster: "SELECT * FROM table" or "SELECT x,y,q FROM table" (from a table with 4 fields)

Question

I'm wondering, what is fastest (or lightest for the database to handle)

Let's say, the db table has 4 fields: x,y,z,q

I only need 3: x,y,q

What way is fastest/easiest for the database to perform (using PHP).. "SELECT * FROM table" or "SELECT x,y,q FROM table"?

Would the same apply if the table had 5 or more fields while I still only needed to select 3?

Answer 1

SELECT x,y,z FROM table is faster because MySQL won't have to look up what columns are in your table before executing the query.

Answer 2

In most databases the * is slower than specifying the fields.

It's also a good programming practice to put all the columns, even though they are many.