Assuming the position

SELECT * FROM gallery2 WHERE topic_id="1509931" UNION SELECT * FROM gallery2 WHERE topic_id="88619" UNION SELECT * FROM gallery2 WHERE topic_id="1593813" UNION SELECT * FROM gallery2 WHERE topic_id="1586584" UNION SELECT * FROM gallery2 WHERE topic_id="315530" UNION SELECT * FROM gallery2 WHERE topic_id="1681108" UNION SELECT * FROM gallery2 WHERE topic_id="865426" UNION SELECT * FROM gallery2 WHERE topic_id="1348840" UNION SELECT * FROM gallery2 WHERE topic_id="340945" UNION SELECT * FROM gallery2 WHERE topic_id="937549" UNION SELECT * FROM gallery2 WHERE topic_id="1391776" UNION SELECT * FROM gallery2 WHERE topic_id="916411" UNION SELECT * FROM gallery2 WHERE topic_id="1084105" UNION SELECT * FROM gallery2 WHERE topic_id="210004" UNION SELECT * FROM gallery2 WHERE topic_id="195878" UNION SELECT * FROM gallery2 WHERE topic_id="225880"