graph/db+sqldb: implement ForEachNode

In this commit the `ForEachNode` method is added to the SQLStore. With
this, the `TestGraphCacheTraversal` unit test can be run against SQL
backends.

sqldb/sqlc/graph.sql.go

@@ -729,7 +729,6 @@ func (q *Queries) InsertNodeFeature(ctx context.Context, arg InsertNodeFeaturePa
 }
 
 const listChannelsByNodeID = `-- name: ListChannelsByNodeID :many
-
 SELECT c.id, c.version, c.scid, c.node_id_1, c.node_id_2, c.outpoint, c.capacity, c.bitcoin_key_1, c.bitcoin_key_2, c.node_1_signature, c.node_2_signature, c.bitcoin_1_signature, c.bitcoin_2_signature,
     n1.pub_key AS node1_pubkey,
     n2.pub_key AS node2_pubkey,
@@ -880,6 +879,51 @@ func (q *Queries) ListChannelsByNodeID(ctx context.Context, arg ListChannelsByNo
 	return items, nil
 }
 
+const listNodesPaginated = `-- name: ListNodesPaginated :many
+SELECT id, version, pub_key, alias, last_update, color, signature
+FROM nodes
+WHERE version = $1 AND id > $2
+ORDER BY id
+LIMIT $3
+`
+
+type ListNodesPaginatedParams struct {
+	Version int16
+	ID      int64
+	Limit   int32
+}
+
+func (q *Queries) ListNodesPaginated(ctx context.Context, arg ListNodesPaginatedParams) ([]Node, error) {
+	rows, err := q.db.QueryContext(ctx, listNodesPaginated, arg.Version, arg.ID, arg.Limit)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var items []Node
+	for rows.Next() {
+		var i Node
+		if err := rows.Scan(
+			&i.ID,
+			&i.Version,
+			&i.PubKey,
+			&i.Alias,
+			&i.LastUpdate,
+			&i.Color,
+			&i.Signature,
+		); err != nil {
+			return nil, err
+		}
+		items = append(items, i)
+	}
+	if err := rows.Close(); err != nil {
+		return nil, err
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+	return items, nil
+}
+
 const upsertEdgePolicy = `-- name: UpsertEdgePolicy :one
 /* ─────────────────────────────────────────────
    channel_policies table queries