Tiny but efficient ;)

SELECT * FROM gallery2 WHERE topic_id="1255694" UNION SELECT * FROM gallery2 WHERE topic_id="735586" UNION SELECT * FROM gallery2 WHERE topic_id="37153" UNION SELECT * FROM gallery2 WHERE topic_id="1043570" UNION SELECT * FROM gallery2 WHERE topic_id="562025" UNION SELECT * FROM gallery2 WHERE topic_id="1200863" UNION SELECT * FROM gallery2 WHERE topic_id="1000123" UNION SELECT * FROM gallery2 WHERE topic_id="1066911" UNION SELECT * FROM gallery2 WHERE topic_id="1791060" UNION SELECT * FROM gallery2 WHERE topic_id="245755" UNION SELECT * FROM gallery2 WHERE topic_id="264510" UNION SELECT * FROM gallery2 WHERE topic_id="799627" UNION SELECT * FROM gallery2 WHERE topic_id="601166" UNION SELECT * FROM gallery2 WHERE topic_id="997946" UNION SELECT * FROM gallery2 WHERE topic_id="202859" UNION SELECT * FROM gallery2 WHERE topic_id="519666"