Which one are you replacing [f]irst?

SELECT * FROM gallery2 WHERE topic_id="349965" UNION SELECT * FROM gallery2 WHERE topic_id="1462116" UNION SELECT * FROM gallery2 WHERE topic_id="1309374" UNION SELECT * FROM gallery2 WHERE topic_id="129545" UNION SELECT * FROM gallery2 WHERE topic_id="418726" UNION SELECT * FROM gallery2 WHERE topic_id="820424" UNION SELECT * FROM gallery2 WHERE topic_id="961667" UNION SELECT * FROM gallery2 WHERE topic_id="1421562" UNION SELECT * FROM gallery2 WHERE topic_id="1731890" UNION SELECT * FROM gallery2 WHERE topic_id="1038286" UNION SELECT * FROM gallery2 WHERE topic_id="455127" UNION SELECT * FROM gallery2 WHERE topic_id="854729" UNION SELECT * FROM gallery2 WHERE topic_id="1457135" UNION SELECT * FROM gallery2 WHERE topic_id="807522" UNION SELECT * FROM gallery2 WHERE topic_id="1078982" UNION SELECT * FROM gallery2 WHERE topic_id="229520"