Merge pull request #33878 from kamipo/fallback_to_unprepared_statement

Fallback to unprepared statement only when bind params limit is exceeded

2 files changed, 10 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb b/activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb
index ad148efcfe..1305216be2 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb
@@ -71,6 +71,11 @@ module ActiveRecord
         256
       end
       deprecate :joins_per_query
+
+      private
+        def bind_params_length
+          65535
+        end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
index fdc9ffa688..5b24a467ec 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
@@ -46,11 +46,16 @@ module ActiveRecord
       def select_all(arel, name = nil, binds = [], preparable: nil)
         arel = arel_from_relation(arel)
         sql, binds = to_sql_and_binds(arel, binds)
+
         if !prepared_statements || (arel.is_a?(String) && preparable.nil?)
           preparable = false
+        elsif binds.length > bind_params_length
+          sql, binds = unprepared_statement { to_sql_and_binds(arel) }
+          preparable = false
         else
           preparable = visitor.preparable
         end
+
         if prepared_statements && preparable
           select_prepared(sql, name, binds)
         else