Results:
[root@mail mysql]# postmap -v -q "test.account@domain.com" mysql:./sender_login_maps.cf
postmap: name_mask: ipv4
postmap: inet_addr_local: configured 3 IPv4 addresses
postmap: cfg_get_str: ./sender_login_maps.cf: user = vmail
postmap: cfg_get_str: ./sender_login_maps.cf: password = *****notimportant*****
postmap: cfg_get_str: ./sender_login_maps.cf: dbname = vmail
postmap: cfg_get_str: ./sender_login_maps.cf: result_format = %s
postmap: cfg_get_int: ./sender_login_maps.cf: expansion_limit = 0
postmap: cfg_get_str: ./sender_login_maps.cf: query = SELECT mailbox.username FROM mailbox,domain WHERE mailbox.username='%s' AND mailbox.domain='%d' AND mailbox.domain=domain.domain AND mailbox.enablesmtp=1 AND mailbox.active=1 AND domain.backupmx=0 AND domain.active=1
postmap: cfg_get_str: ./sender_login_maps.cf: domain =
postmap: cfg_get_str: ./sender_login_maps.cf: hosts = 127.0.0.1
postmap: dict_open: mysql:./sender_login_maps.cf
postmap: dict_mysql_get_active: attempting to connect to host 127.0.0.1
postmap: dict_mysql: successful connection to host 127.0.0.1
postmap: dict_mysql: successful query from host 127.0.0.1
postmap: dict_mysql_lookup: retrieved 1 rows
test.account@domain.com
[root@mail mysql]# postmap -v -q "test.account@domain.com" mysql:./virtual_mailbox_maps.cf
postmap: name_mask: ipv4
postmap: inet_addr_local: configured 3 IPv4 addresses
postmap: cfg_get_str: ./virtual_mailbox_maps.cf: user = vmail
postmap: cfg_get_str: ./virtual_mailbox_maps.cf: password = *****notimportant*****
postmap: cfg_get_str: ./virtual_mailbox_maps.cf: dbname = vmail
postmap: cfg_get_str: ./virtual_mailbox_maps.cf: result_format = %s
postmap: cfg_get_int: ./virtual_mailbox_maps.cf: expansion_limit = 0
postmap: cfg_get_str: ./virtual_mailbox_maps.cf: query = SELECT CONCAT(mailbox.storagenode, '/', mailbox.maildir, '/Maildir/') FROM mailbox,domain WHERE mailbox.username='%s' AND mailbox.active=1 AND mailbox.enabledeliver=1 AND domain.domain = mailbox.domain AND domain.active=1
postmap: cfg_get_str: ./virtual_mailbox_maps.cf: domain =
postmap: cfg_get_str: ./virtual_mailbox_maps.cf: hosts = 127.0.0.1
postmap: dict_open: mysql:./virtual_mailbox_maps.cf
postmap: dict_mysql_get_active: attempting to connect to host 127.0.0.1
postmap: dict_mysql: successful connection to host 127.0.0.1
postmap: dict_mysql: successful query from host 127.0.0.1
postmap: dict_mysql_lookup: retrieved 1 rows
vmail1/yrless.nz/w/a/l/test.account-2016.5.4.8.38.5//Maildir/