diff --git a/lib/active_record/connection_adapters/oracle_enhanced/database_statements.rb b/lib/active_record/connection_adapters/oracle_enhanced/database_statements.rb
index 2b34233d1..0bc96bf1b 100644
--- a/lib/active_record/connection_adapters/oracle_enhanced/database_statements.rb
+++ b/lib/active_record/connection_adapters/oracle_enhanced/database_statements.rb
@@ -12,7 +12,7 @@ module DatabaseStatements
         def execute(sql, name = nil, async: false)
           sql = transform_query(sql)
 
-          log(sql, name, async: async) { @connection.exec(sql) }
+          log(sql, name, async: async) { @raw_connection.exec(sql) }
         end
 
         def exec_query(sql, name = "SQL", binds = [], prepare: false, async: false)
@@ -25,10 +25,10 @@ def exec_query(sql, name = "SQL", binds = [], prepare: false, async: false)
             cached = false
             with_retry do
               if without_prepared_statement?(binds)
-                cursor = @connection.prepare(sql)
+                cursor = @raw_connection.prepare(sql)
               else
                 unless @statements.key? sql
-                  @statements[sql] = @connection.prepare(sql)
+                  @statements[sql] = @raw_connection.prepare(sql)
                 end
 
                 cursor = @statements[sql]
@@ -101,10 +101,10 @@ def exec_insert(sql, name = nil, binds = [], pk = nil, sequence_name = nil)
             returning_id_col = returning_id_index = nil
             with_retry do
               if without_prepared_statement?(binds)
-                cursor = @connection.prepare(sql)
+                cursor = @raw_connection.prepare(sql)
               else
                 unless @statements.key?(sql)
-                  @statements[sql] = @connection.prepare(sql)
+                  @statements[sql] = @raw_connection.prepare(sql)
                 end
 
                 cursor = @statements[sql]
@@ -141,12 +141,12 @@ def exec_update(sql, name = nil, binds = [])
             with_retry do
               cached = false
               if without_prepared_statement?(binds)
-                cursor = @connection.prepare(sql)
+                cursor = @raw_connection.prepare(sql)
               else
                 if @statements.key?(sql)
                   cursor = @statements[sql]
                 else
-                  cursor = @statements[sql] = @connection.prepare(sql)
+                  cursor = @statements[sql] = @raw_connection.prepare(sql)
                 end
 
                 cursor.bind_params(type_casted_binds)
@@ -164,7 +164,7 @@ def exec_update(sql, name = nil, binds = [])
         alias :exec_delete :exec_update
 
         def begin_db_transaction # :nodoc:
-          @connection.autocommit = false
+          @raw_connection.autocommit = false
         end
 
         def transaction_isolation_levels
@@ -183,15 +183,15 @@ def begin_isolated_db_transaction(isolation)
         end
 
         def commit_db_transaction # :nodoc:
-          @connection.commit
+          @raw_connection.commit
         ensure
-          @connection.autocommit = true
+          @raw_connection.autocommit = true
         end
 
         def exec_rollback_db_transaction # :nodoc:
-          @connection.rollback
+          @raw_connection.rollback
         ensure
-          @connection.autocommit = true
+          @raw_connection.autocommit = true
         end
 
         def create_savepoint(name = current_savepoint_name) # :nodoc:
@@ -265,14 +265,14 @@ def write_lobs(table_name, klass, attributes, columns) # :nodoc:
                 raise ActiveRecord::RecordNotFound, "statement #{sql} returned no rows"
               end
               lob = lob_record[col.name]
-              @connection.write_lob(lob, value.to_s, col.type == :binary)
+              @raw_connection.write_lob(lob, value.to_s, col.type == :binary)
             end
           end
         end
 
         private
           def with_retry
-            @connection.with_retry do
+            @raw_connection.with_retry do
               yield
             rescue
               @statements.clear
diff --git a/lib/active_record/connection_adapters/oracle_enhanced/jdbc_connection.rb b/lib/active_record/connection_adapters/oracle_enhanced/jdbc_connection.rb
index e92a5e49e..ab265dec3 100644
--- a/lib/active_record/connection_adapters/oracle_enhanced/jdbc_connection.rb
+++ b/lib/active_record/connection_adapters/oracle_enhanced/jdbc_connection.rb
@@ -295,7 +295,7 @@ def database_version
 
         class Cursor
           def initialize(connection, raw_statement)
-            @connection = connection
+            @raw_connection = connection
             @raw_statement = raw_statement
           end
 
@@ -384,7 +384,7 @@ def fetch(options = {})
               row_values = []
               column_types.each_with_index do |column_type, i|
                 row_values <<
-                  @connection.get_ruby_value_from_result_set(@raw_result_set, i + 1, column_type, get_lob_value)
+                  @raw_connection.get_ruby_value_from_result_set(@raw_result_set, i + 1, column_type, get_lob_value)
               end
               row_values
             else
diff --git a/lib/active_record/connection_adapters/oracle_enhanced/jdbc_quoting.rb b/lib/active_record/connection_adapters/oracle_enhanced/jdbc_quoting.rb
index b75f6bd44..0a13e25a8 100644
--- a/lib/active_record/connection_adapters/oracle_enhanced/jdbc_quoting.rb
+++ b/lib/active_record/connection_adapters/oracle_enhanced/jdbc_quoting.rb
@@ -7,15 +7,15 @@ module JDBCQuoting
         def type_cast(value)
           case value
           when ActiveModel::Type::Binary::Data
-            blob = Java::OracleSql::BLOB.createTemporary(@connection.raw_connection, false, Java::OracleSql::BLOB::DURATION_SESSION)
+            blob = Java::OracleSql::BLOB.createTemporary(@raw_connection.raw_connection, false, Java::OracleSql::BLOB::DURATION_SESSION)
             blob.setBytes(1, value.to_s.to_java_bytes)
             blob
           when Type::OracleEnhanced::Text::Data
-            clob = Java::OracleSql::CLOB.createTemporary(@connection.raw_connection, false, Java::OracleSql::CLOB::DURATION_SESSION)
+            clob = Java::OracleSql::CLOB.createTemporary(@raw_connection.raw_connection, false, Java::OracleSql::CLOB::DURATION_SESSION)
             clob.setString(1, value.to_s)
             clob
           when Type::OracleEnhanced::NationalCharacterText::Data
-            clob = Java::OracleSql::NCLOB.createTemporary(@connection.raw_connection, false, Java::OracleSql::NCLOB::DURATION_SESSION)
+            clob = Java::OracleSql::NCLOB.createTemporary(@raw_connection.raw_connection, false, Java::OracleSql::NCLOB::DURATION_SESSION)
             clob.setString(1, value.to_s)
             clob
           else
diff --git a/lib/active_record/connection_adapters/oracle_enhanced/oci_connection.rb b/lib/active_record/connection_adapters/oracle_enhanced/oci_connection.rb
index a9e42f01c..345bee1b2 100644
--- a/lib/active_record/connection_adapters/oracle_enhanced/oci_connection.rb
+++ b/lib/active_record/connection_adapters/oracle_enhanced/oci_connection.rb
@@ -41,7 +41,7 @@ def raw_oci_connection
           # ActiveRecord Oracle enhanced adapter puts OCI8EnhancedAutoRecover wrapper around OCI8
           # in this case we need to pass original OCI8 connection
           else
-            @raw_connection.instance_variable_get(:@connection)
+            @raw_connection.instance_variable_get(:@raw_connection)
           end
         end
 
@@ -107,7 +107,7 @@ def prepare(sql)
 
         class Cursor
           def initialize(connection, raw_cursor)
-            @connection = connection
+            @raw_connection = connection
             @raw_cursor = raw_cursor
           end
 
@@ -159,7 +159,7 @@ def fetch(options = {})
               get_lob_value = options[:get_lob_value]
               col_index = 0
               row.map do |col|
-                col_value = @connection.typecast_result_value(col, get_lob_value)
+                col_value = @raw_connection.typecast_result_value(col, get_lob_value)
                 col_metadata = @raw_cursor.column_metadata.fetch(col_index)
                 if !col_metadata.nil?
                   key = col_metadata.data_type
@@ -390,15 +390,15 @@ def initialize(config, factory) # :nodoc:
     @active = true
     @config = config
     @factory = factory
-    @connection = @factory.new_connection @config
-    super @connection
+    @raw_connection = @factory.new_connection @config
+    super @raw_connection
   end
 
   # Checks connection, returns true if active. Note that ping actively
   # checks the connection, while #active? simply returns the last
   # known state.
   def ping # :nodoc:
-    @connection.exec("select 1 from dual") { |r| nil }
+    @raw_connection.exec("select 1 from dual") { |r| nil }
     @active = true
   rescue
     @active = false
@@ -409,8 +409,8 @@ def ping # :nodoc:
   def reset! # :nodoc:
     logoff rescue nil
     begin
-      @connection = @factory.new_connection @config
-      __setobj__ @connection
+      @raw_connection = @factory.new_connection @config
+      __setobj__ @raw_connection
       @active = true
     rescue
       @active = false
@@ -442,7 +442,7 @@ def with_retry # :nodoc:
   end
 
   def exec(sql, *bindvars, &block) # :nodoc:
-    with_retry { @connection.exec(sql, *bindvars, &block) }
+    with_retry { @raw_connection.exec(sql, *bindvars, &block) }
   end
 end
 # :startdoc:
diff --git a/lib/active_record/connection_adapters/oracle_enhanced/oci_quoting.rb b/lib/active_record/connection_adapters/oracle_enhanced/oci_quoting.rb
index 80c773e6d..972fe2209 100644
--- a/lib/active_record/connection_adapters/oracle_enhanced/oci_quoting.rb
+++ b/lib/active_record/connection_adapters/oracle_enhanced/oci_quoting.rb
@@ -9,19 +9,19 @@ def type_cast(value)
           when ActiveModel::Type::Binary::Data
             lob_value = value == "" ? " " : value
             bind_type = OCI8::BLOB
-            ora_value = bind_type.new(@connection.raw_oci_connection, lob_value)
+            ora_value = bind_type.new(@raw_connection.raw_oci_connection, lob_value)
             ora_value.size = 0 if value == ""
             ora_value
           when Type::OracleEnhanced::Text::Data
             lob_value = value.to_s == "" ? " " : value.to_s
             bind_type = OCI8::CLOB
-            ora_value = bind_type.new(@connection.raw_oci_connection, lob_value)
+            ora_value = bind_type.new(@raw_connection.raw_oci_connection, lob_value)
             ora_value.size = 0 if value.to_s == ""
             ora_value
           when Type::OracleEnhanced::NationalCharacterText::Data
             lob_value = value.to_s == "" ? " " : value.to_s
             bind_type = OCI8::NCLOB
-            ora_value = bind_type.new(@connection.raw_oci_connection, lob_value)
+            ora_value = bind_type.new(@raw_connection.raw_oci_connection, lob_value)
             ora_value.size = 0 if value.to_s == ""
             ora_value
           else
diff --git a/lib/active_record/connection_adapters/oracle_enhanced/schema_dumper.rb b/lib/active_record/connection_adapters/oracle_enhanced/schema_dumper.rb
index 637c4e877..226049737 100644
--- a/lib/active_record/connection_adapters/oracle_enhanced/schema_dumper.rb
+++ b/lib/active_record/connection_adapters/oracle_enhanced/schema_dumper.rb
@@ -16,7 +16,7 @@ def column_spec_for_primary_key(column)
 
           def tables(stream)
             # do not include materialized views in schema dump - they should be created separately after schema creation
-            sorted_tables = (@connection.tables - @connection.materialized_views).sort
+            sorted_tables = (@raw_connection.tables - @raw_connection.materialized_views).sort
             sorted_tables.each do |tbl|
               # add table prefix or suffix for schema_migrations
               next if ignored? tbl
@@ -34,7 +34,7 @@ def tables(stream)
           end
 
           def synonyms(stream)
-            syns = @connection.synonyms
+            syns = @raw_connection.synonyms
             syns.each do |syn|
               next if ignored? syn.name
               table_name = syn.table_name
@@ -46,7 +46,7 @@ def synonyms(stream)
           end
 
           def _indexes(table, stream)
-            if (indexes = @connection.indexes(table)).any?
+            if (indexes = @raw_connection.indexes(table)).any?
               add_index_statements = indexes.filter_map do |index|
                 case index.type
                 when nil
@@ -77,7 +77,7 @@ def _indexes(table, stream)
           end
 
           def indexes_in_create(table, stream)
-            if (indexes = @connection.indexes(table)).any?
+            if (indexes = @raw_connection.indexes(table)).any?
               index_statements = indexes.map do |index|
                 "    t.index #{index_parts(index).join(', ')}" unless index.type == "CTXSYS.CONTEXT"
               end
@@ -92,24 +92,24 @@ def index_parts(index)
           end
 
           def table(table, stream)
-            columns = @connection.columns(table)
+            columns = @raw_connection.columns(table)
             begin
               self.table_name = table
 
               tbl = StringIO.new
 
               # first dump primary key column
-              if @connection.respond_to?(:primary_keys)
-                pk = @connection.primary_keys(table)
+              if @raw_connection.respond_to?(:primary_keys)
+                pk = @raw_connection.primary_keys(table)
                 pk = pk.first unless pk.size > 1
               else
-                pk = @connection.primary_key(table)
+                pk = @raw_connection.primary_key(table)
               end
 
               tbl.print "  create_table #{remove_prefix_and_suffix(table).inspect}"
 
               # addition to make temporary option work
-              tbl.print ", temporary: true" if @connection.temporary_table?(table)
+              tbl.print ", temporary: true" if @raw_connection.temporary_table?(table)
 
               case pk
               when String
@@ -128,7 +128,7 @@ def table(table, stream)
                 tbl.print ", id: false"
               end
 
-              table_options = @connection.table_options(table)
+              table_options = @raw_connection.table_options(table)
               if table_options.present?
                 tbl.print ", #{format_options(table_options)}"
               end
@@ -137,7 +137,7 @@ def table(table, stream)
 
               # then dump all non-primary key columns
               columns.each do |column|
-                raise StandardError, "Unknown type '#{column.sql_type}' for column '#{column.name}'" unless @connection.valid_type?(column.type)
+                raise StandardError, "Unknown type '#{column.sql_type}' for column '#{column.name}'" unless @raw_connection.valid_type?(column.type)
                 next if column.name == pk
                 type, colspec = column_spec(column)
                 tbl.print "    t.#{type} #{column.name.inspect}"
@@ -166,7 +166,7 @@ def table(table, stream)
           def prepare_column_options(column)
             spec = super
 
-            if @connection.supports_virtual_columns? && column.virtual?
+            if @raw_connection.supports_virtual_columns? && column.virtual?
               spec[:as] = extract_expression_for_virtual_column(column)
               spec = { type: schema_type(column).inspect }.merge!(spec) unless column.type == :decimal
             end
@@ -180,7 +180,7 @@ def default_primary_key?(column)
 
           def extract_expression_for_virtual_column(column)
             column_name = column.name
-            @connection.select_value(<<~SQL.squish, "SCHEMA", [bind_string("table_name", table_name.upcase), bind_string("column_name", column_name.upcase)]).inspect
+            @raw_connection.select_value(<<~SQL.squish, "SCHEMA", [bind_string("table_name", table_name.upcase), bind_string("column_name", column_name.upcase)]).inspect
               select /*+ OPTIMIZER_FEATURES_ENABLE('11.2.0.2') */ data_default from all_tab_columns
               where owner = SYS_CONTEXT('userenv', 'current_schema')
               and table_name = :table_name
diff --git a/lib/active_record/connection_adapters/oracle_enhanced/schema_statements.rb b/lib/active_record/connection_adapters/oracle_enhanced/schema_statements.rb
index 516ac371c..8c2d95c58 100644
--- a/lib/active_record/connection_adapters/oracle_enhanced/schema_statements.rb
+++ b/lib/active_record/connection_adapters/oracle_enhanced/schema_statements.rb
@@ -53,7 +53,7 @@ def table_exists?(table_name)
         end
 
         def data_source_exists?(table_name)
-          (_owner, _table_name) = @connection.describe(table_name)
+          (_owner, _table_name) = @raw_connection.describe(table_name)
           true
         rescue
           false
@@ -87,7 +87,7 @@ def synonyms
         end
 
         def indexes(table_name) # :nodoc:
-          (_owner, table_name) = @connection.describe(table_name)
+          (_owner, table_name) = @raw_connection.describe(table_name)
           default_tablespace_name = default_tablespace
 
           result = select_all(<<~SQL.squish, "SCHEMA", [bind_string("table_name", table_name)])
@@ -368,7 +368,7 @@ def index_name(table_name, options) # :nodoc:
         #
         # Will always query database and not index cache.
         def index_name_exists?(table_name, index_name)
-          (_owner, table_name) = @connection.describe(table_name)
+          (_owner, table_name) = @raw_connection.describe(table_name)
           result = select_value(<<~SQL.squish, "SCHEMA", [bind_string("table_name", table_name), bind_string("index_name", index_name.to_s.upcase)])
             SELECT /*+ OPTIMIZER_FEATURES_ENABLE('11.2.0.2') */ 1 FROM all_indexes i
             WHERE i.owner = SYS_CONTEXT('userenv', 'current_schema')
@@ -511,7 +511,7 @@ def change_column_comment(table_name, column_name, comment_or_changes)
 
         def table_comment(table_name) # :nodoc:
           # TODO
-          (_owner, table_name) = @connection.describe(table_name)
+          (_owner, table_name) = @raw_connection.describe(table_name)
           select_value(<<~SQL.squish, "SCHEMA", [bind_string("table_name", table_name)])
             SELECT /*+ OPTIMIZER_FEATURES_ENABLE('11.2.0.2') */ comments FROM all_tab_comments
             WHERE owner = SYS_CONTEXT('userenv', 'current_schema')
@@ -527,7 +527,7 @@ def table_options(table_name) # :nodoc:
 
         def column_comment(table_name, column_name) # :nodoc:
           # TODO: it  does not exist in Abstract adapter
-          (_owner, table_name) = @connection.describe(table_name)
+          (_owner, table_name) = @raw_connection.describe(table_name)
           select_value(<<~SQL.squish, "SCHEMA", [bind_string("table_name", table_name), bind_string("column_name", column_name.upcase)])
             SELECT /*+ OPTIMIZER_FEATURES_ENABLE('11.2.0.2') */ comments FROM all_col_comments
             WHERE owner = SYS_CONTEXT('userenv', 'current_schema')
@@ -555,7 +555,7 @@ def tablespace(table_name)
 
         # get table foreign keys for schema dump
         def foreign_keys(table_name) # :nodoc:
-          (_owner, desc_table_name) = @connection.describe(table_name)
+          (_owner, desc_table_name) = @raw_connection.describe(table_name)
 
           fk_info = select_all(<<~SQL.squish, "SCHEMA", [bind_string("desc_table_name", desc_table_name)])
             SELECT /*+ OPTIMIZER_FEATURES_ENABLE('11.2.0.2') */ r.table_name to_table
diff --git a/lib/active_record/connection_adapters/oracle_enhanced_adapter.rb b/lib/active_record/connection_adapters/oracle_enhanced_adapter.rb
index d625d334a..51ce19129 100644
--- a/lib/active_record/connection_adapters/oracle_enhanced_adapter.rb
+++ b/lib/active_record/connection_adapters/oracle_enhanced_adapter.rb
@@ -426,12 +426,12 @@ def native_database_types # :nodoc:
 
       def auto_retry=(value) # :nodoc:
         @auto_retry = value
-        @connection.auto_retry = value if @connection
+        @raw_connection.auto_retry = value if @raw_connection
       end
 
       # return raw OCI8 or JDBC connection
       def raw_connection
-        @connection.raw_connection
+        @raw_connection.raw_connection
       end
 
       # Returns true if the connection is active.
@@ -440,7 +440,7 @@ def active? # :nodoc:
         # #active? method is also available, but that simply returns the
         # last known state, which isn't good enough if the connection has
         # gone stale since the last use.
-        @connection.ping
+        @raw_connection.ping
       rescue OracleEnhanced::ConnectionException
         false
       end
@@ -448,7 +448,7 @@ def active? # :nodoc:
       # Reconnects to the database.
       def reconnect! # :nodoc:
         super
-        @connection.reset!
+        @raw_connection.reset!
       rescue OracleEnhanced::ConnectionException => e
         @logger.warn "#{adapter_name} automatic reconnection failed: #{e.message}" if @logger
       end
@@ -461,12 +461,12 @@ def reset!
       # Disconnects from the database.
       def disconnect! # :nodoc:
         super
-        @connection.logoff rescue nil
+        @raw_connection.logoff rescue nil
       end
 
       def discard!
         super
-        @connection = nil
+        @raw_connection = nil
       end
 
       # use in set_sequence_name to avoid fetching primary key value from sequence
@@ -491,7 +491,7 @@ def prefetch_primary_key?(table_name = nil)
         table_name = table_name.to_s
         do_not_prefetch = @do_not_prefetch_primary_key[table_name]
         if do_not_prefetch.nil?
-          owner, desc_table_name = @connection.describe(table_name)
+          owner, desc_table_name = @raw_connection.describe(table_name)
           @do_not_prefetch_primary_key[table_name] = do_not_prefetch = !has_primary_key?(table_name, owner, desc_table_name)
         end
         !do_not_prefetch
@@ -560,7 +560,7 @@ def default_tablespace
       end
 
       def column_definitions(table_name)
-        (owner, desc_table_name) = @connection.describe(table_name)
+        (owner, desc_table_name) = @raw_connection.describe(table_name)
 
         select_all(<<~SQL.squish, "SCHEMA", [bind_string("owner", owner), bind_string("table_name", desc_table_name)])
           SELECT /*+ OPTIMIZER_FEATURES_ENABLE('11.2.0.2') */ cols.column_name AS name, cols.data_type AS sql_type,
@@ -592,7 +592,7 @@ def clear_table_columns_cache(table_name)
       # Find a table's primary key and sequence.
       # *Note*: Only primary key is implemented - sequence will be nil.
       def pk_and_sequence_for(table_name, owner = nil, desc_table_name = nil) # :nodoc:
-        (owner, desc_table_name) = @connection.describe(table_name)
+        (owner, desc_table_name) = @raw_connection.describe(table_name)
 
         seqs = select_values_forcing_binds(<<~SQL.squish, "SCHEMA", [bind_string("owner", owner), bind_string("sequence_name", default_sequence_name(desc_table_name))])
           select /*+ OPTIMIZER_FEATURES_ENABLE('11.2.0.2') */ us.sequence_name
@@ -634,7 +634,7 @@ def has_primary_key?(table_name, owner = nil, desc_table_name = nil) # :nodoc:
       end
 
       def primary_keys(table_name) # :nodoc:
-        (_owner, desc_table_name) = @connection.describe(table_name)
+        (_owner, desc_table_name) = @raw_connection.describe(table_name)
 
         pks = select_values_forcing_binds(<<~SQL.squish, "SCHEMA", [bind_string("table_name", desc_table_name)])
           SELECT /*+ OPTIMIZER_FEATURES_ENABLE('11.2.0.2') */ cc.column_name
@@ -679,7 +679,7 @@ def max_identifier_length
       alias index_name_length max_identifier_length
 
       def get_database_version
-        @connection.database_version
+        @raw_connection.database_version
       end
 
       def check_version
@@ -749,7 +749,7 @@ def extract_limit(sql_type) # :nodoc:
       end
 
       def translate_exception(exception, message:, sql:, binds:) # :nodoc:
-        case @connection.error_code(exception)
+        case @raw_connection.error_code(exception)
         when 1
           RecordNotUnique.new(message, sql: sql, binds: binds)
         when 60
diff --git a/lib/arel/visitors/oracle.rb b/lib/arel/visitors/oracle.rb
index 5bcab245b..78e239d8d 100644
--- a/lib/arel/visitors/oracle.rb
+++ b/lib/arel/visitors/oracle.rb
@@ -94,8 +94,8 @@ def visit_Arel_Nodes_Except(o, collector)
         # To avoid ORA-01795: maximum number of expressions in a list is 1000
         # tell ActiveRecord to limit us to 1000 ids at a time
         def visit_Arel_Nodes_HomogeneousIn(o, collector)
-          in_clause_length = @connection.in_clause_length
-          values = o.casted_values.map { |v| @connection.quote(v) }
+          in_clause_length = @raw_connection.in_clause_length
+          values = o.casted_values.map { |v| @raw_connection.quote(v) }
           column_name = quote_table_name(o.table_name) + "." + quote_column_name(o.column_name)
           operator =
             if o.type == :in
@@ -110,7 +110,7 @@ def visit_Arel_Nodes_HomogeneousIn(o, collector)
 
             expr =
               if values.empty?
-                @connection.quote(nil)
+                @raw_connection.quote(nil)
               else
                 values.join(",")
               end
diff --git a/lib/arel/visitors/oracle12.rb b/lib/arel/visitors/oracle12.rb
index 02572ed48..e55976c6f 100644
--- a/lib/arel/visitors/oracle12.rb
+++ b/lib/arel/visitors/oracle12.rb
@@ -47,8 +47,8 @@ def visit_Arel_Nodes_Except(o, collector)
         # To avoid ORA-01795: maximum number of expressions in a list is 1000
         # tell ActiveRecord to limit us to 1000 ids at a time
         def visit_Arel_Nodes_HomogeneousIn(o, collector)
-          in_clause_length = @connection.in_clause_length
-          values = o.casted_values.map { |v| @connection.quote(v) }
+          in_clause_length = @raw_connection.in_clause_length
+          values = o.casted_values.map { |v| @raw_connection.quote(v) }
           column_name = quote_table_name(o.table_name) + "." + quote_column_name(o.column_name)
           operator =
             if o.type == :in
@@ -63,7 +63,7 @@ def visit_Arel_Nodes_HomogeneousIn(o, collector)
 
             expr =
               if values.empty?
-                @connection.quote(nil)
+                @raw_connection.quote(nil)
               else
                 values.join(",")
               end
diff --git a/lib/arel/visitors/oracle_common.rb b/lib/arel/visitors/oracle_common.rb
index 72ba8517b..89c8f58f9 100644
--- a/lib/arel/visitors/oracle_common.rb
+++ b/lib/arel/visitors/oracle_common.rb
@@ -39,7 +39,7 @@ def cached_column_for(attr)
         end
 
         def schema_cache
-          @connection.schema_cache
+          @raw_connection.schema_cache
         end
     end
   end
diff --git a/spec/active_record/connection_adapters/oracle_enhanced/connection_spec.rb b/spec/active_record/connection_adapters/oracle_enhanced/connection_spec.rb
index eed87dde0..3bae4a806 100644
--- a/spec/active_record/connection_adapters/oracle_enhanced/connection_spec.rb
+++ b/spec/active_record/connection_adapters/oracle_enhanced/connection_spec.rb
@@ -414,7 +414,7 @@ def lookup(path)
 
     before(:all) do
       ActiveRecord::Base.establish_connection(CONNECTION_PARAMS)
-      @conn = ActiveRecord::Base.connection.instance_variable_get("@connection")
+      @conn = ActiveRecord::Base.connection.instance_variable_get("@raw_connection")
       @sys_conn = ActiveRecord::ConnectionAdapters::OracleEnhanced::Connection.create(SYS_CONNECTION_PARAMS)
       schema_define do
         create_table :posts, force: true
diff --git a/spec/active_record/oracle_enhanced/type/dirty_spec.rb b/spec/active_record/oracle_enhanced/type/dirty_spec.rb
index f10ef9d81..9766da3a4 100644
--- a/spec/active_record/oracle_enhanced/type/dirty_spec.rb
+++ b/spec/active_record/oracle_enhanced/type/dirty_spec.rb
@@ -113,7 +113,7 @@ class TestEmployee < ActiveRecord::Base
 
   it "should not update unchanged CLOBs" do
     @conn = nil
-    @connection = nil
+    @raw_connection = nil
     @employee = TestEmployee.create!(
       comments: "initial"
     )
@@ -121,7 +121,7 @@ class TestEmployee < ActiveRecord::Base
     @employee.reload
     expect(@employee.comments).to eq("initial")
 
-    oci_conn = @conn.instance_variable_get("@connection")
+    oci_conn = @conn.instance_variable_get("@raw_connection")
     class << oci_conn
       def write_lob(lob, value, is_binary = false); raise "don't do this'"; end
     end