1 Here's a quick (incomplete!) overview of what winds up in your tables.
6 +----------------------------+
8 +------------------+---------+
10 +------------------+---------+
11 | adam@example.net | herp |
12 +------------------+---------+
15 +------------------------------------------------------+
17 +-----+------------------+----------+------------------+
18 | sid | user_from | calendar | user_which |
19 +-----+------------------+----------+------------------+
20 | 1 | adam@example.net | derp | beth@example.net |
21 +-----+------------------+----------+------------------+
26 +-------------------------------------------------------+
28 +---------+--------+----------------+-------------------+
29 | user_no | active | joined | username |
30 +---------+--------+----------------+-------------------+
31 | 17 | t | 2014-01-04 ... | alice@example.com |
32 +---------+--------+----------------+-------------------+
34 +-----------------------------------------+
36 +---------+--------------+----------------+
37 | user_no | setting_name | setting_value |
38 +---------+--------------+----------------+
39 | 17 | dumb setting | its dumb value |
40 +---------+--------------+----------------+
58 +----------------------------------------------+
60 +-------------------+-------------+------------+
61 | username | domain | local_part |
62 +-------------------+-------------+------------+
63 | alice@example.com | example.com | alice |
64 +-------------------+-------------+------------+
65 | bob@example.com | example.com | bob |
66 +-------------------+-------------+------------+
67 | adam@example.net | example.net | adam |
68 +-------------------+-------------+------------+
69 | beth@example.net | example.net | beth |
70 +-------------------+-------------+------------+
71 | carol@example.net | example.net | carol |
72 +-------------------+-------------+------------+
75 +------------------------------------------------------+
77 +-------------------+-------------------+--------------+
78 | address | goto | domain |
79 +-------------------+-------------------+--------------+
80 | alice@example.com | alice@example.com | example.com |
81 +-------------------+-------------------+--------------+
82 | bob@example.com | bob@example.com | example.com |
83 +-------------------+-------------------+--------------+
84 | adam@example.net | adam@example.net | example.net |
85 +-------------------+-------------------+--------------+
86 | beth@example.net | beth@example.net | example.net |
87 +-------------------+-------------------+--------------+
88 | carol@example.net | carol@example.net | example.net |
89 +-------------------+-------------------+--------------+
92 +---------------------------------+
94 +-------------------+-------------+
96 +-------------------+-------------+
97 | admin@example.com | example.com |
98 +-------------------+-------------+
99 | admin@example.com | example.net |
100 +-------------------+-------------+
107 +---------+-------------------+
108 | user_id | username |
109 +---------+-------------------+
110 | 1 | alice@example.com |
111 +---------+-------------------+
112 | 2 | adam@example.net |
113 +---------+-------------------+