Merge pull request #2769 from poanetwork/ab-optimize-token-token-transfers-query

optimize token token transfers query

CHANGELOG.md

@@ -18,11 +18,12 @@
 - [#2470](https://github.com/poanetwork/blockscout/pull/2470) - Allow Realtime Fetcher to wait for small skips
 
 ### Fixes
-- [#2755](https://github.com/poanetwork/blockscout/pull/2755) - various token instance fetcher fixes
 - [#2770](https://github.com/poanetwork/blockscout/pull/2770) - do not re-fetch token instances without uris
+- [#2769](https://github.com/poanetwork/blockscout/pull/2769) - optimize token token transfers query
 - [#2761](https://github.com/poanetwork/blockscout/pull/2761) - add indexes for token instances fetching queries
 - [#2767](https://github.com/poanetwork/blockscout/pull/2767) - fix websocket subscriptions with token instances
 - [#2765](https://github.com/poanetwork/blockscout/pull/2765) - fixed width issue for cards in mobile view for Transaction Details page
+- [#2755](https://github.com/poanetwork/blockscout/pull/2755) - various token instance fetcher fixes
 - [#2753](https://github.com/poanetwork/blockscout/pull/2753) - fix nft token instance images
 - [#2750](https://github.com/poanetwork/blockscout/pull/2750) - fixed contract buttons color for NFT token instance on each theme
 - [#2746](https://github.com/poanetwork/blockscout/pull/2746) - fixed wrong alignment in logs decoded view

apps/explorer/priv/repo/migrations/20191009121635_add_token_transfer_sorting_indexes.exs

@@ -0,0 +1,12 @@
+defmodule Explorer.Repo.Migrations.AddTokenTransferSortingIndexes do
+  use Ecto.Migration
+
+  def change do
+    create(
+      index(
+        :token_transfers,
+        ["block_number DESC", "log_index DESC"]
+      )
+    )
+  end
+end