[Dovecot] tables between dovecot and postfix and a paradoxical question

Dear all,

I read we create the following table in wiki2 : CREATE TABLE users ( userid VARCHAR(128) NOT NULL, domain VARCHAR(128) NOT NULL, password VARCHAR(64) NOT NULL, home VARCHAR(255) NOT NULL, uid INTEGER NOT NULL, gid INTEGER NOT NULL );

But i read the following text in the official postfix documentation : "DO create tables with each matching item as a key and with an arbitrary value. With SQL databases it is not uncommon to return the key itself or a constant value." ref: http://www.postfix.org/mysql_table.5.html

How can i combine together?

--mohsen