graph/db+sqldb: delete channels in batches

Use the new `SLICES` directive to add a DeleteChannels query which takes
a set of DB channel IDs. Then replace all our calls to DeleteChannel
with a paginated call to DeleteChannels.

sqldb/sqlc/graph.sql.go

@@ -143,15 +143,6 @@ func (q *Queries) CreateChannelExtraType(ctx context.Context, arg CreateChannelE
 	return err
 }
 
-const deleteChannel = `-- name: DeleteChannel :exec
-DELETE FROM graph_channels WHERE id = $1
-`
-
-func (q *Queries) DeleteChannel(ctx context.Context, id int64) error {
-	_, err := q.db.ExecContext(ctx, deleteChannel, id)
-	return err
-}
-
 const deleteChannelPolicyExtraTypes = `-- name: DeleteChannelPolicyExtraTypes :exec
 DELETE FROM graph_channel_policy_extra_types
 WHERE channel_policy_id = $1
@@ -162,6 +153,26 @@ func (q *Queries) DeleteChannelPolicyExtraTypes(ctx context.Context, channelPoli
 	return err
 }
 
+const deleteChannels = `-- name: DeleteChannels :exec
+DELETE FROM graph_channels
+WHERE id IN (/*SLICE:ids*/?)
+`
+
+func (q *Queries) DeleteChannels(ctx context.Context, ids []int64) error {
+	query := deleteChannels
+	var queryParams []interface{}
+	if len(ids) > 0 {
+		for _, v := range ids {
+			queryParams = append(queryParams, v)
+		}
+		query = strings.Replace(query, "/*SLICE:ids*/?", makeQueryParams(len(queryParams), len(ids)), 1)
+	} else {
+		query = strings.Replace(query, "/*SLICE:ids*/?", "NULL", 1)
+	}
+	_, err := q.db.ExecContext(ctx, query, queryParams...)
+	return err
+}
+
 const deleteExtraNodeType = `-- name: DeleteExtraNodeType :exec
 DELETE FROM graph_node_extra_types
 WHERE node_id = $1

sqldb/sqlc/querier.go

@@ -18,8 +18,8 @@ type Querier interface {
 	CreateChannel(ctx context.Context, arg CreateChannelParams) (int64, error)
 	CreateChannelExtraType(ctx context.Context, arg CreateChannelExtraTypeParams) error
 	DeleteCanceledInvoices(ctx context.Context) (sql.Result, error)
-	DeleteChannel(ctx context.Context, id int64) error
 	DeleteChannelPolicyExtraTypes(ctx context.Context, channelPolicyID int64) error
+	DeleteChannels(ctx context.Context, ids []int64) error
 	DeleteExtraNodeType(ctx context.Context, arg DeleteExtraNodeTypeParams) error
 	DeleteInvoice(ctx context.Context, arg DeleteInvoiceParams) (sql.Result, error)
 	DeleteNode(ctx context.Context, id int64) error

sqldb/sqlc/queries/graph.sql

@@ -569,8 +569,9 @@ WHERE c.version = $1 AND c.id > $2
 ORDER BY c.id
 LIMIT $3;
 
--- name: DeleteChannel :exec
-DELETE FROM graph_channels WHERE id = $1;
+-- name: DeleteChannels :exec
+DELETE FROM graph_channels
+WHERE id IN (sqlc.slice('ids')/*SLICE:ids*/);
 
 /* ─────────────────────────────────────────────
    graph_channel_features table queries