Performance across Database Links

When pulling a lot of data through a database link you can speed up the process enormously by hinting at which table is on a remote site. This table will be processed at that site (or something similar):

SELECT /*+DRIVING_SITE(C)*/
A.FIELD
, B.FIELD
, C.FIELD
FROM
PS_TABLE_A A
, PS_TABLE_B B
, PS_TABLE_C@RA C
WHERE A.KEY_FIELD = x
AND A.KEY_FIELD = B.KEY_FIELD
AND C.KEY_FIELD2 = C.KEY_FIELD2;

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