I have an insert statement before these updates: On db.sumbitchanges the error is shown.
Topic top = (from t in db.Topics
where t.id == id
select t).SingleOrDefault();
top.lastpost = username + maxdate;
Category ca = (from c in db.Categories
where c.categoryid == cat
select c).SingleOrDefault();
ca.totaltopics = ca.totaltopics + 1;
ca.posts = ca.posts + 1;
ca.lastpost = username + maxdate;
db.SubmitChanges();
It sounds like either top.lastpost or ca.lastpost (or both) doesn't have enough space on the db to hold username + maxdate.
Check how many characters the database fields allow and either change the field to allow more characters or reduce the length of the output - perhaps only storing username + maxdate.ToString("yyyy-MM-dd") or username + maxdate.ToString("yyyy-MM-dd HH:mm:ss")?
I assume both Topic.lastpost and Category.lastpost are strings, and username + maxdate concatenates two strings. The result might be a bit bigger than what would fit into lastpost column in respective table.
The string is longer than the size of the DB column so the resulting data doesn't fit inside.
