Write a postgre SQL statement to drop the existing primary from the table locations on a combination of columns location_id and country_id.
Here is the structure of the table locations.
postgres=# \d locations
Column | Type | Modifiers
----------------+-----------------------+-----------
location_id | numeric(4,0) | not null
street_address | character varying(40) |
postal_code | character varying(12) |
city | character varying(30) |
state_province | character varying(25) |
country_id | character varying(2) | not null
Indexes:
"locations_pkey" PRIMARY KEY, btree (location_id, country_id)
Output:
Now see the structure of the table locations after alteration.
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