do not use left join

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do not use left join

no lef join

erdsah88

8:12 am on Jul 16, 2007 (gmt 0)

don't use left join especially on big tables.

using normal join requires more code.. but at the end of the day it is the best u can get.

aspdaddy

6:26 pm on Jul 16, 2007 (gmt 0)

you need left join only if you allow nulls on foreign key columns. So yeah, do not use left join :)

Demaestro

6:29 pm on Jul 16, 2007 (gmt 0)

what DB are you using?

I use them successfully in extremely large DBs. But I am using PostGres.

Lilliabeth

2:06 am on Jul 23, 2007 (gmt 0)

That is interesting, I must be missing something though. I guess MySQL is different than other database types? (I don't have any experience with MYSQL, but am pretty good with data modelling.)

In MySQL:

What if I want to see a list of all my customers and their addresses, but I don't have addresses for some customers?
I want to see products data and sales data for all products, including products that have never had a sale?
I want to see information on all 2000 employees, to include the 7 fields that are carried only for the 3 people who are vested?

Thanks. I am always into learning new things.