sql - SQLite select statement pulls all values although it is not supposed to -

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i have these 3 tables:

create table "item" (     "itemid" integer primary key ,     "itemname" varchar(25),      buyerid integer references buyer(buyerid),      sellerid integer references seller(sellerid) );  create table buyer(     buyerid integer primary key unique not null,     fname varchar(25),     lname varchar(25),     itemid integer,     foreign key (itemid) references item(itemid) );  create table seller(     sellerid integer primary key unique not null,     fname varchar(25),     lname varchar(25),     itemid integer,     foreign key (itemid) references item(itemid) );  item table has: 1|poly|1|1 2|jute|2|2 3|salt|3|3  buyer table has: 1|buyer1|polybuyer|1 2|buyer2|jutebuyer|2 3|buyer3|saltbuyer|3  sellertable has: 1|seller1|polyseller|1 2|seller2|juteseller|2 3|seller3|saltseller|3

now want select query want itemname , first , last names of relevant buyers , sellers. suppose want list of buyers , sellers salt. query:

select buyer.fname, buyer.lname, itemname, seller.fname, seller.lname  buyer, seller, item  item.itemid = 3;

i expect return:

buyer3|saltbuyer|salt|seller3|saltseller

but instead get:

buyer1|polybuyer|salt|seller1|polyseller buyer1|polybuyer|salt|seller2|juteseller buyer1|polybuyer|salt|seller3|saltseller buyer2|jutebuyer|salt|seller1|polyseller buyer2|jutebuyer|salt|seller2|juteseller buyer2|jutebuyer|salt|seller3|saltseller buyer3|saltbuyer|salt|seller1|polyseller buyer3|saltbuyer|salt|seller2|juteseller buyer3|saltbuyer|salt|seller3|saltseller

so messing up? bad database design or bad query or both? thank in advance.

you need use join combine 3 tables based on primary key-foreign key relation, example :

select buyer.fname, buyer.lname, itemname, seller.fname, seller.lname  item     inner join seller on item.itemid = seller.itemid     inner join buyer  on item.itemid = buyer.itemid item.itemid = 3;

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