Transactions stats: get min/max blocks in one query

CHANGELOG.md

@@ -14,6 +14,7 @@
 - [#3888](https://github.com/blockscout/blockscout/pull/3888) - EIP-1967 contract proxy pattern detection fix
 
 ### Chore
+- [#4231](https://github.com/blockscout/blockscout/pull/4231) - Transactions stats: get min/max blocks in one query
 - [#4157](https://github.com/blockscout/blockscout/pull/4157) - Fix internal docs generation
 - [#4127](https://github.com/blockscout/blockscout/pull/4127) - Update ex_keccak package
 - [#4063](https://github.com/blockscout/blockscout/pull/4063) - Do not display 4bytes signature in the tx tile for contract creation

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

@@ -25,27 +25,13 @@ defmodule Explorer.Chain.Transaction.History.Historian do
       earliest = datetime(day_to_fetch, ~T[00:00:00])
       latest = datetime(day_to_fetch, ~T[23:59:59])
 
-      min_block_query =
+      min_max_block_query =
         from(block in Block,
           where: block.timestamp >= ^earliest and block.timestamp <= ^latest,
-          group_by: block.number,
-          order_by: [asc: min(block.number)],
-          limit: 1,
-          select: min(block.number)
+          select: {min(block.number), max(block.number)}
         )
 
-      min_block = Repo.one(min_block_query, timeout: :infinity)
-
-      max_block_query =
-        from(block in Block,
-          where: block.timestamp >= ^earliest and block.timestamp <= ^latest,
-          group_by: block.number,
-          order_by: [desc: max(block.number)],
-          limit: 1,
-          select: max(block.number)
-        )
-
-      max_block = Repo.one(max_block_query, timeout: :infinity)
+      {min_block, max_block} = Repo.one(min_max_block_query, timeout: :infinity)
 
       if min_block && max_block do
         all_transactions_query =