first version of sultion

src/Core/Settings.h

@@ -1158,6 +1158,7 @@ class IColumn;
     M(Bool, input_format_values_accurate_types_of_literals, true, "For Values format: when parsing and interpreting expressions using template, check actual type of literal to avoid possible overflow and precision issues.", 0) \
     M(Bool, input_format_values_allow_data_after_semicolon, false, "For Values format: allow extra data after semicolon (used by client to interpret comments).", 0) \
     M(Bool, input_format_avro_allow_missing_fields, false, "For Avro/AvroConfluent format: when field is not found in schema use default value instead of error", 0) \
+    M(Bool, cast_keys_to_string_from_json, false, "Either to cast string to int in enumerating json or not", 0) \
     /** This setting is obsolete and do nothing, left for compatibility reasons. */ \
     M(Bool, input_format_avro_null_as_default, false, "For Avro/AvroConfluent format: insert default in case of null and non Nullable column", 0) \
     M(UInt64, format_binary_max_string_size, 1_GiB, "The maximum allowed size for String in RowBinary format. It prevents allocating large amount of memory in case of corrupted data. 0 means there is no limit", 0) \

src/DataTypes/EnumValues.cpp

@@ -1,6 +1,9 @@
 #include <DataTypes/EnumValues.h>
 #include <boost/algorithm/string.hpp>
 #include <base/sort.h>
+#include "Core/Names.h"
+#include <Common/CurrentThread.h>
+#include <Interpreters/Context.h>
 
 
 namespace DB
@@ -52,7 +55,23 @@ void EnumValues<T>::fillMaps()
 template <typename T>
 T EnumValues<T>::getValue(StringRef field_name, bool try_treat_as_id) const
 {
-    const auto it = name_to_value_map.find(field_name);
+    ContextPtr query_context;
+    if (CurrentThread::isInitialized())
+    {
+        query_context = CurrentThread::get().getGlobalContext();
+    }
+
+    auto it = name_to_value_map.find(field_name);
+    if (!it && query_context && query_context->getSettingsRef().cast_keys_to_string_from_json)
+    {
+        for (const auto& item : name_to_value_map)
+        {
+            if (item.getValue().second == std::stoi(field_name.toString()))
+            {
+                it = name_to_value_map.find(item.getKey());
+            }
+        }
+    }
     if (!it)
     {
         /// It is used in CSV and TSV input formats. If we fail to find given string in

tests/queries/0_stateless/03202_enum_json_cast.sql

@@ -0,0 +1,10 @@
+SET cast_keys_to_string_from_json=1;
+DROP TABLE test;
+CREATE TABLE test
+(
+    `answer` Enum8('Question' = 1, 'Answer' = 2, 'Wiki' = 3, 'TagWikiExcerpt' = 4, 'TagWiki' = 5, 'ModeratorNomination' = 6, 'WikiPlaceholder' = 7, 'PrivilegeWiki' = 8)
+)
+ENGINE = Memory;
+INSERT INTO test FORMAT JSONEachRow {"answer": 1};
+INSERT INTO test FORMAT JSONEachRow {"answer": "2"};
+SELECT * FROM test;