The error message "permission denied for relation table" in PostgreSQL indicates that the user attempting to access the specified table does not have the required permissions to perform the operation.

To resolve this issue, you can try the following steps:

1. Check the user's permissions: Make sure the user has the necessary privileges to perform the desired operation on the table. You can do this by connecting to the PostgreSQL server as a superuser or a user with sufficient privileges and running the following query:

SELECT table_name, privilege_type
FROM information_schema.table_privileges
WHERE table_name = '<table>';

This will show you the current privileges granted to various users on the specified table. If the user in question does not have the required privileges, you will need to grant them.

2. Grant necessary permissions: To grant the required permissions to the user, you can use the GRANT statement. For example, if the user needs SELECT permission on the table:
GRANT SELECT ON TABLE <table> TO <user>;

Replace table with the name of the table and user with the name of the user or role that needs access.

3. Check schema permissions: In PostgreSQL, permissions can also be set at the schema level. Ensure that the user has the necessary privileges on the schema that contains the table.
To check the schema-level permissions:
SELECT schema_name, privilege_type
FROM information_schema.schema_privileges
WHERE schema_name = '<schema_name>';

To grant permissions on the schema:
GRANT USAGE ON SCHEMA <schema_name> TO <user>;
GRANT SELECT ON ALL TABLES IN SCHEMA <schema_name> TO <user>;

Replace schema _ name with the name of the schema containing the table and user with the appropriate user or role.

4. Check database permissions: If the table is located in a specific database, make sure the user has the necessary privileges on that database.
To check database-level permissions:
\ l
\ c <database_name>
\ dp

To grant permissions on the database:
GRANT CONNECT ON DATABASE <database_name> TO <user>;

Replace database name with the name of the database and user with the appropriate user or role.

5. Refresh permissions: After making changes to the permissions, it's a good practice to refresh them to ensure they take effect immediately:
\c <database_name>
\dp <table>

Alternatively, you can disconnect and reconnect from the PostgreSQL server.

Remember that only users with sufficient privileges, like the database superuser, can grant permissions to other users. Be cautious when granting permissions and only give the minimum required privileges for security reasons.