Process reviewr comments

apps/explorer/lib/explorer/chain.ex

@@ -1324,16 +1324,13 @@ defmodule Explorer.Chain do
 
   @spec fetch_sum_coin_total_supply() :: non_neg_integer
   def fetch_sum_coin_total_supply do
-    {:ok, burn_address_hash} = Explorer.Chain.string_to_address_hash("0x0000000000000000000000000000000000000000")
-
     query =
       from(
         a0 in Address,
-        select: fragment("SUM(a0.fetched_coin_balance)"),
-        where: a0.hash != ^burn_address_hash
+        select: fragment("SUM(a0.fetched_coin_balance)")
       )
 
-    Repo.one!(query)
+    Repo.one!(query) || 0
   end
 
   @doc """

apps/explorer/test/explorer/chain_test.exs

@@ -1121,6 +1121,20 @@ defmodule Explorer.ChainTest do
     end
   end
 
+  describe "fetch_sum_coin_total_supply/0" do
+    test "fetches coin total supply" do
+      for index <- 0..4 do
+        insert(:address, fetched_coin_balance: index)
+      end
+
+      assert "10" = Decimal.to_string(Chain.fetch_sum_coin_total_supply())
+    end
+
+    test "fetches coin total supply when there are no blocks" do
+      assert 0 = Chain.fetch_sum_coin_total_supply()
+    end
+  end
+
   describe "address_hash_to_token_transfers/2" do
     test "returns just the token transfers related to the given contract address" do
       contract_address =