From 77e8f457e006a0f151a67050b61ba844764e1b05 Mon Sep 17 00:00:00 2001
From: zachdaniel <zachary.s.daniel@gmail.com>
Date: Wed, 29 May 2019 14:06:23 -0400
Subject: [PATCH] fix: uniq by hash, instead of transaction

---
 CHANGELOG.md                                  |  1 +
 apps/explorer/lib/explorer/chain.ex           |  2 +-
 .../lib/explorer/chain/token_transfer.ex      | 60 +++----------------
 3 files changed, 11 insertions(+), 52 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 775c006a5c..84592d868b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -46,6 +46,7 @@
 - [#2008](https://github.com/poanetwork/blockscout/pull/2008) - add new function clause for xDai network beneficiaries
 - [#2009](https://github.com/poanetwork/blockscout/pull/2009) - addresses page improvements
 - [#2027](https://github.com/poanetwork/blockscout/pull/2027) - fix: `BlocksTransactionsMismatch` ignoring blocks without transactions
+- [#2062](https://github.com/poanetwork/blockscout/pull/2062) - fix: uniq by hash, instead of transaction
 
 ### Chore
 
diff --git a/apps/explorer/lib/explorer/chain.ex b/apps/explorer/lib/explorer/chain.ex
index 9446388531..cc2375c2ef 100644
--- a/apps/explorer/lib/explorer/chain.ex
+++ b/apps/explorer/lib/explorer/chain.ex
@@ -266,7 +266,7 @@ defmodule Explorer.Chain do
 
     queries
     |> Stream.flat_map(&Repo.all/1)
-    |> Stream.uniq()
+    |> Stream.uniq_by(& &1.hash)
     |> Stream.concat(rewards_list)
     |> Enum.sort_by(fn item ->
       case item do
diff --git a/apps/explorer/lib/explorer/chain/token_transfer.ex b/apps/explorer/lib/explorer/chain/token_transfer.ex
index fa7ba99347..905d576aa1 100644
--- a/apps/explorer/lib/explorer/chain/token_transfer.ex
+++ b/apps/explorer/lib/explorer/chain/token_transfer.ex
@@ -204,59 +204,17 @@ defmodule Explorer.Chain.TokenTransfer do
     transaction_hashes_from_token_transfers_sql(address_bytes, paging_options)
   end
 
-  defp transaction_hashes_from_token_transfers_sql(address_bytes, %PagingOptions{key: nil, page_size: page_size}) do
-    {:ok, %Postgrex.Result{rows: transaction_hashes_from_token_transfers}} =
-      Repo.query(
-        """
-          SELECT transaction_hash
-          FROM
-          (
-          SELECT transaction_hash
-          FROM token_transfers
-          WHERE from_address_hash = $1
-
-          UNION
-
-          SELECT transaction_hash
-          FROM token_transfers
-          WHERE to_address_hash = $1
-          ) as token_transfers_transaction_hashes
-          LIMIT $2
-        """,
-        [address_bytes, page_size]
-      )
-
-    List.flatten(transaction_hashes_from_token_transfers)
-  end
-
-  defp transaction_hashes_from_token_transfers_sql(address_bytes, %PagingOptions{
-         key: {block_number, _index},
-         page_size: page_size
-       }) do
-    {:ok, %Postgrex.Result{rows: transaction_hashes_from_token_transfers}} =
-      Repo.query(
-        """
-          SELECT transaction_hash
-          FROM
-          (
-          SELECT transaction_hash
-          FROM token_transfers
-          WHERE from_address_hash = $1
-          AND block_number < $2
-
-          UNION
-
-          SELECT transaction_hash
-          FROM token_transfers
-          WHERE to_address_hash = $1
-          AND block_number < $2
-          ) as token_transfers_transaction_hashes
-          LIMIT $3
-        """,
-        [address_bytes, block_number, page_size]
+  defp transaction_hashes_from_token_transfers_sql(address_bytes, %PagingOptions{page_size: page_size} = paging_options) do
+    query =
+      from(token_transfer in TokenTransfer,
+        where: token_transfer.to_address_hash == ^address_bytes or token_transfer.from_address_hash == ^address_bytes,
+        select: type(token_transfer.transaction_hash, :binary),
+        limit: ^page_size
       )
 
-    List.flatten(transaction_hashes_from_token_transfers)
+    query
+    |> page_transaction_hashes_from_token_transfers(paging_options)
+    |> Repo.all()
   end
 
   defp page_transaction_hashes_from_token_transfers(query, %PagingOptions{key: nil}), do: query