What is more efficient(faster): to store the same tweet twice in Tweet
table, once for user1
and again for user2
or using join between Tweet
and Friend
to get the results ?
Tweet => Id
UserId
SenderId
JSONdata
User => Id
Friend => UserId
FriendId
with join :
SELECT TOP 20 a.* FROM Tweet a INNER JOIN Friend b ON a.SenderId = b.UserId WHERE b.UserId = {0}
or I can save the tweet twice for the sender and the receiver and use a simple query :
SELECT TOP 20 * FROM TWEET WHERE UserId = {0}
which one is more faster, if joins then what type of index should I use, I'll be happy to hear any advice.
thanx
Store your data only once (Tweet) and you will not have any consistency issues. Unless you are developing this as a heavy OLAP system (ie data warehouse), then you should be normalizing.
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