Add a joint primary key in oracle and an oracle joint primary key

Add a joint primary key in oracle and an oracle joint primary key

Alter table tablename add constraint unionkeyname primary key (column1, column2 );

In the preceding statement:

Tablename is the table for which the Union constraint is to be added.

Unionkeyname is the name of the added Union constraint.

Column1 and column2 are the names of the two columns used by the Union primary key.

Oracle joint primary key Creation

Alter table xxx add constraints xxx_pk primary key (c1, c2, c3, c4, c5 ....);

In Oracle, how does one set the Union primary key? (Example)

Set during table Creation
Create table tab (
ID1 NUMBER (10 ),
ID2 NUMBER (4 ),
Credit number (2 ),
CONSTRAINT PK_TAB primary key (ID1, ID2) -- PRIMARY KEY
);
Or append after creating the table
Alter table tab add constraint pk_tab2 primary key (id1, id2 );