Somehow this got lost in the rebase..

src/github.com/matrix-org/dendrite/clientapi/storage/output_room_events_table.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 
 	"github.com/lib/pq"
+	"github.com/matrix-org/gomatrixserverlib"
 )
 
 const outputRoomEventsSchema = `

src/github.com/matrix-org/dendrite/clientapi/storage/syncserver.go

@@ -13,6 +13,7 @@ type SyncServerDatabase struct {
 	db         *sql.DB
 	partitions common.PartitionOffsetStatements
 	events     outputRoomEventsStatements
+	roomstate  currentRoomStateStatements
 }
 
 // NewSyncServerDatabase creates a new sync server database
@@ -30,7 +31,11 @@ func NewSyncServerDatabase(dataSourceName string) (*SyncServerDatabase, error) {
 	if err = events.prepare(db); err != nil {
 		return nil, err
 	}
-	return &SyncServerDatabase{db, partitions, events}, nil
+	state := currentRoomStateStatements{}
+	if err := state.prepare(db); err != nil {
+		return nil, err
+	}
+	return &SyncServerDatabase{db, partitions, events, state}, nil
 }
 
 // WriteEvent into the database. It is not safe to call this function from multiple goroutines, as it would create races
@@ -69,3 +74,22 @@ func (d *SyncServerDatabase) PartitionOffsets(topic string) ([]common.PartitionO
 func (d *SyncServerDatabase) SetPartitionOffset(topic string, partition int32, offset int64) error {
 	return d.partitions.UpsertPartitionOffset(topic, partition, offset)
 }
+
+func runTransaction(db *sql.DB, fn func(txn *sql.Tx) error) (err error) {
+	txn, err := db.Begin()
+	if err != nil {
+		return
+	}
+	defer func() {
+		if r := recover(); r != nil {
+			txn.Rollback()
+			panic(r)
+		} else if err != nil {
+			txn.Rollback()
+		} else {
+			err = txn.Commit()
+		}
+	}()
+	err = fn(txn)
+	return
+}