SQL

add primary key to existing table sql

alter table Persion add primary key (persionId,Pname,PMID)

add primary key to existing table sql

ALTER TABLE `tblauto`
  ADD PRIMARY KEY (`id`);

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how add a PRIMARY KEY column TO SQL table

ALTER TABLE old_table ADD pk_column INT AUTO_INCREMENT PRIMARY KEY;

add primary key to database sql

CREATE TABLE Persons (
    ID int NOT NULL,
    LastName varchar(255) NOT NULL,
    FirstName varchar(255),
    Age int,
    PRIMARY KEY (ID)
);