I'll try and break up my questions the other day about extdata that went unanswered into pieces in the hopes it will be more specific and clear.
In general, I am trying to figure out the syntax of the map statement and what is allowed in that statement. So, by map statement, I mean for example perhaps the dovecot-dict-expire.conf.ext file as shown in the doc. Is the syntax the same for the various types of files (quota vs expire)? Is there syntax to allow the specification of a different key? If so, where is this documented. I have an existing table I want to use, not the table shown in the doc.
The reason I am asking is I have seen web pages that reference all sorts of statements within the map statement, and I have no idea where they are documented. Specifically, I see an example here (which is LDAP), look in section 3:
http://dovecot.org/patches/1.2/ldap/HOWTO_dictldap+extdata.txt
You will see lots of statements, not sure which ones can be used for MySQL (instead of LDAP). So, would like to find a list of ALL valid syntax within the map.