Mail-list implementation (database design) -

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i refactoring web-app. right there 'contact' table has one-to-one correspondence main 'client' table, bool indicating if clients want receive mail. mail-list accessed once per month, , clients' profile page accessed many times day. thinking if 'cleaner' make new table client ids of in mail-list, querying if key in table should take same time accessing information. should that, or should leave is?

thanks, joyce

an association table (clientid, emailid) normalized form. think better keep this. if want show contact emailid in ui screen, can avoid inner join overhead due new association table.

however in future if came across requirement have multiple emailids associated clientid, think creating association table then.


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