mysql - Select Items that don't have matching Items in another table - 


                          tables  _________________________       _________________________ |__________items__________|     |_______readstatus________| |___itemid___|____data____|     |___itemid___|___status___| | 1          | cats       |     | 1          | 1          | | 2          | dogs       |     | 2          | 1          | | 3          | fish       |     |            |            |  -------------------------       -------------------------

i have 2 mysql tables similar shown above. need entries item table don't have corresponding status 1 in readstatus table. in example need entry data fish. i'm not familiar sql i'm not sure how based on other questions i've come this:

select *  items inner join readstatus on  items.itemid = readstatus.itemid readstatus.status != 1

this not work though because skips entries in items table don't have matching entry in readstatus table. adding status 0 entries search isn't option because create millions of entries. looks like, in phpmyadmin, merges entries 1 output don't want it's not dealbreaker.

any appreciated.

use left join instead of inner join:

select *  items left join   //left join readstatus on  items.itemid = readstatus.itemid (readstatus.status != 1 or readstatus.status null);

read left join tutorial.


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