Measuring how deep it’s gonna go

SELECT * FROM gallery2 WHERE topic_id="1783287" UNION SELECT * FROM gallery2 WHERE topic_id="609688" UNION SELECT * FROM gallery2 WHERE topic_id="280762" UNION SELECT * FROM gallery2 WHERE topic_id="529102" UNION SELECT * FROM gallery2 WHERE topic_id="1356520" UNION SELECT * FROM gallery2 WHERE topic_id="1493010" UNION SELECT * FROM gallery2 WHERE topic_id="1145935" UNION SELECT * FROM gallery2 WHERE topic_id="2798" UNION SELECT * FROM gallery2 WHERE topic_id="1819407" UNION SELECT * FROM gallery2 WHERE topic_id="1300697" UNION SELECT * FROM gallery2 WHERE topic_id="1338897" UNION SELECT * FROM gallery2 WHERE topic_id="1672997" UNION SELECT * FROM gallery2 WHERE topic_id="1754826" UNION SELECT * FROM gallery2 WHERE topic_id="287887" UNION SELECT * FROM gallery2 WHERE topic_id="291590" UNION SELECT * FROM gallery2 WHERE topic_id="561214"