change primary key sql code example

Example 1: change primary key sql

ALTER TABLE 
DROP CONSTRAINT 

ALTER TABLE 
ADD CONSTRAINT  PRIMARY KEY (,)

Example 2: sql primary key

-- NOTE: this is for SQL-Oracle specifically

-- example:
SELECT cols.table_name, cols.column_name, cols.position, cons.status, cons.owner
FROM all_constraints cons, all_cons_columns cols
WHERE cols.table_name = 'CUSTOMERS' 
AND cons.constraint_type = 'P'
AND cons.constraint_name = cols.constraint_name
AND cons.owner = cols.owner;

-- syntax:
SELECT cols.table_name, cols.column_name, cols.position, cons.status, cons.owner
FROM all_constraints cons, all_cons_columns cols
WHERE cols.table_name = '' -- Replace  with your table-name
AND cons.constraint_type = 'P'
AND cons.constraint_name = cols.constraint_name
AND cons.owner = cols.owner;