1
vote
1answer
50 views

How to UPDATE a column by COUNT of FK from another table?

How to extend this query for the entire table, to update all ids? UPDATE table1 SET number=( SELECT COUNT(*) FROM table2 where id=1 ) WHERE id=1 id is the PRIMARY KEY in table1 and FK in table2. ...
3
votes
2answers
385 views

Should I use select count(*) for counting records or having a field like comments_no for tables like post, comments?

In my recent project which is about social networking for an Asian country, I'm in doubt whether I use the below SQL statement for counting records: SELECT COUNT(id) shareLikeNo FROM ...