1 files changed, 15 insertions, 5 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index 8001c0dd53..710b5cd887 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -601,7 +601,11 @@ module ActiveRecord
 
         def exec_no_cache(sql, name, binds)
           type_casted_binds = type_casted_binds(binds)
-          log(sql, name, binds, type_casted_binds) { @connection.async_exec(sql, type_casted_binds) }
+          log(sql, name, binds, type_casted_binds) do
+            ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+              @connection.async_exec(sql, type_casted_binds)
+            end
+          end
         end
 
         def exec_cache(sql, name, binds)
@@ -609,7 +613,9 @@ module ActiveRecord
           type_casted_binds = type_casted_binds(binds)
 
           log(sql, name, binds, type_casted_binds, stmt_key) do
-            @connection.exec_prepared(stmt_key, type_casted_binds)
+            ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+              @connection.exec_prepared(stmt_key, type_casted_binds)
+            end
           end
         rescue ActiveRecord::StatementInvalid => e
           raise unless is_cached_plan_failure?(e)
@@ -750,7 +756,7 @@ module ActiveRecord
                      col_description(a.attrelid, a.attnum) AS comment
                 FROM pg_attribute a LEFT JOIN pg_attrdef d
                   ON a.attrelid = d.adrelid AND a.attnum = d.adnum
-               WHERE a.attrelid = '#{quote_table_name(table_name)}'::regclass
+               WHERE a.attrelid = #{quote(quote_table_name(table_name))}::regclass
                  AND a.attnum > 0 AND NOT a.attisdropped
                ORDER BY a.attnum
           end_sql
@@ -771,10 +777,14 @@ module ActiveRecord
             sql = <<-end_sql
               SELECT exists(
                 SELECT * FROM pg_proc
+                WHERE proname = 'lower'
+                  AND proargtypes = ARRAY[#{quote column.sql_type}::regtype]::oidvector
+              ) OR exists(
+                SELECT * FROM pg_proc
                 INNER JOIN pg_cast
-                  ON casttarget::text::oidvector = proargtypes
+                  ON ARRAY[casttarget]::oidvector = proargtypes
                 WHERE proname = 'lower'
-                  AND castsource = '#{column.sql_type}'::regtype::oid
+                  AND castsource = #{quote column.sql_type}::regtype
               )
             end_sql
             execute_and_clear(sql, "SCHEMA", []) do |result|