fix(setup): reenable index creation (#9868)

# Which Problems Are Solved

We saw high CPU usage if many events were created on the database. This
was caused by the new actions which query for all event types and
aggregate types.

# How the Problems Are Solved

- the handler of action execution does not filter for aggregate and
event types.
- the index for `instance_id` and `position` is reenabled.

# Additional Changes

none

# Additional Context

none

cmd/setup/54.go

@@ -23,5 +23,5 @@ func (mig *InstancePositionIndex) Execute(ctx context.Context, _ eventstore.Even
 }
 
 func (mig *InstancePositionIndex) String() string {
-	return "54_instance_position_index_remove"
+	return "54_instance_position_index_again"
 }

cmd/setup/54.sql

@@ -1 +1 @@
-DROP INDEX IF EXISTS eventstore.es_instance_position;
+CREATE INDEX CONCURRENTLY IF NOT EXISTS es_instance_position ON eventstore.events2 (instance_id, position);

internal/eventstore/handler/v2/handler.go

@@ -60,6 +60,7 @@ type Handler struct {
 	requeueEvery     time.Duration
 	txDuration       time.Duration
 	now              nowFunc
+	queryGlobal      bool
 
 	triggeredInstancesSync sync.Map
 
@@ -143,6 +144,11 @@ type Projection interface {
 	Reducers() []AggregateReducer
 }
 
+type GlobalProjection interface {
+	Projection
+	FilterGlobalEvents()
+}
+
 func NewHandler(
 	ctx context.Context,
 	config *Config,
@@ -185,6 +191,10 @@ func NewHandler(
 		metrics: metrics,
 	}
 
+	if _, ok := projection.(GlobalProjection); ok {
+		handler.queryGlobal = true
+	}
+
 	return handler
 }
 
@@ -676,6 +686,10 @@ func (h *Handler) eventQuery(currentState *state) *eventstore.SearchQueryBuilder
 		}
 	}
 
+	if h.queryGlobal {
+		return builder
+	}
+
 	aggregateTypes := make([]eventstore.AggregateType, 0, len(h.eventTypes))
 	eventTypes := make([]eventstore.EventType, 0, len(h.eventTypes))
 

internal/execution/handlers.go

@@ -84,6 +84,9 @@ func (u *eventHandler) Reducers() []handler.AggregateReducer {
 	return aggReducers
 }
 
+// FilterGlobalEvents implements [handler.GlobalProjection]
+func (u *eventHandler) FilterGlobalEvents() {}
+
 func groupsFromEventType(s string) []string {
 	parts := strings.Split(s, ".")
 	groups := make([]string, len(parts))