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The check clause check(P),where Pis a predicate Example:Declare branch name as the primary key for branch and ensure that the values of assets are non- negative. create table branch (branch name char(15), branch city char(30), assets integer, primary key (branch_name), check(assets >=0)) Database System Concepts,5th Edition,Oct 5.2006 4.12 Silberschatz,Korth and SudarshanDatabase System Concepts, 5th Edition, Oct 5. 2006 4.12 ©Silberschatz, Korth and Sudarshan The check clause check (P ), where P is a predicate Example: Declare branch_name as the primary key for branch and ensure that the values of assets are non￾negative. create table branch (branch_name char(15), branch_city char(30), assets integer, primary key (branch_name), check (assets >= 0))
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