update meta data

Task/SQL-based-authentication/00DESCRIPTION

@@ -0,0 +1,15 @@
+This task has three parts:
+* Connect to a [[MySQL]] database (<tt>connect_db</tt>)
+* Create user/password records in the following table (<tt>create_user</tt>)
+* Authenticate login requests against the table (<tt>authenticate_user</tt>)
+
+This is the table definition:
+<lang sql>create table users (
+    userid int primary key auto_increment,
+    username varchar(32) unique key not null,
+    pass_salt tinyblob not null,
+            -- a string of 16 random bytes
+    pass_md5 tinyblob not null
+            -- binary MD5 hash of pass_salt concatenated with the password
+);</lang>
+(<tt>pass_salt</tt> and <tt>pass_md5</tt> would be <tt>binary(16)</tt> values, but MySQL versions before 5.0.15 strip trailing spaces when selecting them.)