Please help me how to write a Query to change the primary
key constraint from 1 attribute to another attribute in a
table
Answers were Sorted based on User's Feedback
Answer / dinesh a.
You can assing only one primary key on a table , so you
can't modify directoly one column to another , you need to
drop first one then create on another attribute.
SQL>ct constraint_name,constraint_type from user_constraints
where table_name='EMP' and constraint_type='P';
CONSTRAINT_NAME C
------------------------------ -
SYS_C00125220 P
SQL> alter table emp drop constraint SYS_C00125220;
sql> alter table any_table add constraint my_cons_nm
primary key(column_of_tab)
Is This Answer Correct ? | 6 Yes | 1 No |
Answer / chandana
YOU CANNOT CHANGE THE CONSTRAINTS DIRECTLY ON A COLUMN.
FIRST DROP THE CONSTARINT U HAVE CREATED AND THEN USE ALTER
COMMAND TO ADD CONSTARINT TO THE CORRECT COLUMN.
Is This Answer Correct ? | 3 Yes | 0 No |
Answer / manvendra
ALTER TABLE TABLE_NAME
MODIFY COLUMN (COLUMN2 PRIMARY KEY);
Is This Answer Correct ? | 1 Yes | 5 No |
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