sqldb: add index on node & chan policy last_update columns

So that we can have efficient lookups during the "*UpdatesInHorizon"
calls.

Author: ellemouton

sqldb/sqlc/migrations/000007_graph.down.sql

@@ -3,6 +3,7 @@ DROP INDEX IF EXISTS nodes_unique;
 DROP INDEX IF EXISTS node_extra_types_unique;
 DROP INDEX IF EXISTS node_features_unique;
 DROP INDEX IF EXISTS node_addresses_unique;
+DROP INDEX IF EXISTS node_last_update_idx;
 DROP INDEX IF EXISTS source_nodes_unique;
 DROP INDEX IF EXISTS channels_node_id_1_idx;
 DROP INDEX IF EXISTS channels_node_id_2_idx;
@@ -12,6 +13,7 @@ DROP INDEX IF EXISTS channel_features_unique;
 DROP INDEX IF EXISTS channel_extra_types_unique;
 DROP INDEX IF EXISTS channel_policies_unique;
 DROP INDEX IF EXISTS channel_policy_extra_types_unique;
+DROP INDEX IF EXISTS channel_policy_last_update_idx;
 
 -- Drop tables in order of reverse dependencies.
 DROP TABLE IF EXISTS channel_policy_extra_types;

sqldb/sqlc/migrations/000007_graph.up.sql

@@ -37,6 +37,7 @@ CREATE TABLE IF NOT EXISTS nodes (
 CREATE UNIQUE INDEX IF NOT EXISTS nodes_unique ON nodes (
     pub_key, version
 );
+CREATE INDEX IF NOT EXISTS node_last_update_idx ON nodes(last_update);
 
 -- node_extra_types stores any extra TLV fields covered by a node announcement that
 -- we do not have an explicit column for in the nodes table.
@@ -273,6 +274,7 @@ CREATE TABLE IF NOT EXISTS channel_policies (
 CREATE UNIQUE INDEX IF NOT EXISTS channel_policies_unique ON channel_policies (
     channel_id, node_id, version
 );
+CREATE INDEX IF NOT EXISTS channel_policy_last_update_idx ON channel_policies(last_update);
 
 -- channel_policy_extra_types stores any extra TLV fields covered by a channel
 -- update that we do not have an explicit column for in the channel_policies