condition in sql query c
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I have `tbl_ticket_categories(id , category_name , description , site_referers_id)`

`tbl_ticket_repliers(id , user_id , category_id , site_referers_id)`

`tbl_users(id , role_id , username , password )`

I have to select all category_name,description from tbl_ticket_categories where site_referers_id = 1

and those username whose user_id is in tbl_ticket_repliers.