Split address transactions query into separate query/fetches and combine the results due to postgres not selecting optimized query plan consistently

apps/explorer/lib/explorer/chain.ex

@@ -182,14 +182,29 @@ defmodule Explorer.Chain do
       when is_list(options) do
     direction = Keyword.get(options, :direction)
     necessity_by_association = Keyword.get(options, :necessity_by_association, %{})
+    paging_options = Keyword.get(options, :paging_options, @default_paging_options)
 
-    options
-    |> Keyword.get(:paging_options, @default_paging_options)
+    transaction_matches = paging_options
     |> fetch_transactions()
     |> Transaction.where_address_fields_match(address_hash, direction)
     |> join_associations(necessity_by_association)
     |> Transaction.preload_token_transfers(address_hash)
     |> Repo.all()
+
+    token_transfer_matches = paging_options
+    |> fetch_transactions()
+    |> TokenTransfer.where_address_fields_match(address_hash, direction)
+    |> join_associations(necessity_by_association)
+    |> Transaction.preload_token_transfers(address_hash)
+    |> Repo.all()
+
+    transaction_matches
+    |> MapSet.new()
+    |> MapSet.union(MapSet.new(token_transfer_matches))
+    |> MapSet.to_list()
+    |> Enum.sort_by(& &1.block_number, &>=/2)
+    |> Enum.sort_by(& &1.index, &>=/2)
+    |> Enum.slice(0..paging_options.page_size)
   end
 
   @doc """

apps/explorer/lib/explorer/chain/token_transfer.ex

@@ -148,4 +148,22 @@ defmodule Explorer.Chain.TokenTransfer do
       token_transfer.inserted_at < ^inserted_at
     )
   end
+
+  def where_address_fields_match(query, address_hash, :from) do
+    query
+    |> join(:left, [transaction], tt in assoc(transaction, :token_transfers))
+    |> where([_transaction, tt], tt.from_address_hash == ^address_hash)
+  end
+
+  def where_address_fields_match(query, address_hash, :to) do
+    query
+    |> join(:left, [transaction], tt in assoc(transaction, :token_transfers))
+    |> where([_transaction, tt], tt.to_address_hash == ^address_hash)
+  end
+
+  def where_address_fields_match(query, address_hash, _) do
+    query
+    |> join(:left, [transaction], tt in assoc(transaction, :token_transfers))
+    |> where([_transaction, tt], tt.to_address_hash == ^address_hash or tt.from_address_hash == ^address_hash)
+  end
 end

apps/explorer/lib/explorer/chain/transaction.ex

@@ -3,7 +3,7 @@ defmodule Explorer.Chain.Transaction do
 
   use Explorer.Schema
 
-  import Ecto.Query, only: [from: 2, join: 5, preload: 3]
+  import Ecto.Query, only: [from: 2, preload: 3, where: 3]
 
   alias Ecto.Changeset
 
@@ -424,90 +424,19 @@ defmodule Explorer.Chain.Transaction do
   to token_contract_address_hash, to_address_hash or from_address_hash from Token Transfers's table.
   """
   def where_address_fields_match(query, address_hash, :to) do
-    join(
-      query,
-      :inner,
-      [transaction],
-      matches in fragment(
-        """
-        WITH hashes AS (
-          (
-            SELECT t0.hash AS hash
-            FROM transactions AS t0
-            WHERE t0.to_address_hash = ? OR t0.created_contract_address_hash = ?
-          )
-          UNION ALL
-          (
-            SELECT tt.transaction_hash AS hash
-            FROM token_transfers AS tt
-            WHERE tt.to_address_hash = ?
-          )
-        ) SELECT * from hashes
-        """,
-        ^address_hash.bytes,
-        ^address_hash.bytes,
-        ^address_hash.bytes
-      ),
-      transaction.hash == matches.hash
-    )
+    where(query, [t], t.to_address_hash == ^address_hash or t.created_contract_address_hash == ^address_hash)
   end
 
   def where_address_fields_match(query, address_hash, :from) do
-    join(
-      query,
-      :inner,
-      [transaction],
-      matches in fragment(
-        """
-        WITH hashes AS (
-          (
-            SELECT t0.hash AS hash
-            FROM transactions AS t0
-            WHERE t0.from_address_hash = ?
-          )
-          UNION ALL
-          (
-            SELECT tt.transaction_hash AS hash
-            FROM token_transfers AS tt
-            WHERE tt.from_address_hash = ?
-          )
-        ) SELECT * from hashes
-        """,
-        ^address_hash.bytes,
-        ^address_hash.bytes
-      ),
-      transaction.hash == matches.hash
-    )
+    where(query, [t], t.from_address_hash == ^address_hash or t.created_contract_address_hash == ^address_hash)
   end
 
   def where_address_fields_match(query, address_hash, nil) do
-    join(
+    where(
       query,
-      :inner,
-      [transaction],
-      matches in fragment(
-        """
-        WITH hashes AS (
-          (
-            SELECT t0.hash AS hash
-            FROM transactions AS t0
-            WHERE t0.to_address_hash = ? OR t0.from_address_hash = ? OR t0.created_contract_address_hash = ?
-          )
-          UNION ALL
-          (
-            SELECT tt.transaction_hash AS hash
-            FROM token_transfers AS tt
-            WHERE tt.to_address_hash = ? OR tt.from_address_hash = ?
-          )
-        ) SELECT * from hashes
-        """,
-        ^address_hash.bytes,
-        ^address_hash.bytes,
-        ^address_hash.bytes,
-        ^address_hash.bytes,
-        ^address_hash.bytes
-      ),
-      transaction.hash == matches.hash
+      [t],
+      t.to_address_hash == ^address_hash or t.from_address_hash == ^address_hash or
+        t.created_contract_address_hash == ^address_hash
     )
   end