diff --git a/master/html/ch04s02.html b/master/html/ch04s02.html
index ea3f9ca..f811f5d 100644
--- a/master/html/ch04s02.html
+++ b/master/html/ch04s02.html
@@ -182,7 +182,7 @@
 GROUP BY trip_id, service_id, route_id, date;
 
 INSERT INTO trips_mdb(trip_id, service_id, route_id, date, trip)
-SELECT trip_id, route_id, t.service_id, d.date,
+SELECT trip_id, t.service_id, route_id, d.date,
   shift(trip, make_interval(days => d.date - t.date))
 FROM trips_mdb t JOIN service_dates d ON t.service_id = d.service_id AND t.date <> d.date;
 			</pre><p>
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index 1ff5cda..13d2040 100644
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diff --git a/master/mobilitydb-workshop.pdf b/master/mobilitydb-workshop.pdf
index 6bd1b84..c5e55cc 100644
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