diff --git a/spec/internal/db/schema.rb b/spec/internal/db/schema.rb
index be49301..d6d06ec 100644
--- a/spec/internal/db/schema.rb
+++ b/spec/internal/db/schema.rb
@@ -27,7 +27,7 @@
     t.hstore :params
   end
 
-  add_index :stats_by_days, [:record_id, :column_id, :date], unique: true
+  add_index :stats_by_days, [:record_id, :column_id, :date, :params], unique: true, name: :uq
 
   create_table :stats_totals do |t|
     t.integer :record_id, null: false
@@ -37,7 +37,7 @@
     t.hstore :params
   end
 
-  add_index :stats_totals, [:record_id, :column_id], unique: true
+  add_index :stats_totals, [:record_id, :column_id, :params], unique: true
 
   create_table :stats_agg_totals do |t|
     t.integer :record_id, null: false
diff --git a/spec/lib/redis_counters/dumpers/engine_spec.rb b/spec/lib/redis_counters/dumpers/engine_spec.rb
index fc354de..308b0e8 100644
--- a/spec/lib/redis_counters/dumpers/engine_spec.rb
+++ b/spec/lib/redis_counters/dumpers/engine_spec.rb
@@ -26,6 +26,7 @@
         key_fields :record_id, :column_id, :params
         increment_fields :hits
         map :hits, to: :value
+        map :params, to: "COALESCE(params, '')"
       end
 
       destination do