Use more efficient query

See cockroachdb/cockroach#4925 (comment)
cockroachdb · Mar 14, 2016 · c595ef6 · c595ef6
1 parent 991ed04
commit c595ef6
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/photos/db.go b/photos/db.go
@@ -315,8 +315,10 @@ func listComments(tx *sql.Tx, userID int, commentIDs *[][]byte) ([]byte, error)
 	if err != nil {
 		return nil, err
 	}
-	const selectSQL = `
-SELECT commentID, userID, message, timestamp FROM comments WHERE photoID = $1 ORDER BY timestamp DESC LIMIT 100`
+	const selectSQL = `SELECT commentID, userID, message, timestamp FROM comments ` +
+		`WHERE photoID = $1 AND commentID IN ` +
+		`(SELECT commentID FROM comments WHERE photoID = $1 ORDER BY timestamp DESC LIMIT 100)` +
+		`ORDER BY timestamp DESC`
 	rows, err := tx.Query(selectSQL, photoID)
 	switch {
 	case err == sql.ErrNoRows: