Which of the following SQL queries would be faster? A join on two tables or successive queries?

Question

I have two tables here:

ITEMS
ID| DETAILS| .....| OWNER

USERS:
ID| NAME|....

Where ITEMS.OWNER = USERS.ID

I'm listing the items out with their respective owners names. For this I could use a join on both tables or I could select all the ITEMS and loop through them making a sql query to retrieve the tuple of that itmes owner. Thats like:

1 sql with a JOIN versus 1x20 single table sql queries

Which would be a better apporach to take in terms of speed? Thanks

Answer 1

Of course a JOIN will be faster.

Making 20 queries will imply:

• Parsing them 20 times
• Making 20 index seeks to find the start of the index range on items
• Returning 20 recordsets (each with its own metadata).