2 files changed, 9 insertions, 1 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index 1c4e625ead..381d5ab29b 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -609,6 +609,10 @@ module ActiveRecord
         FEATURE_NOT_SUPPORTED = "0A000" #:nodoc:
 
         def execute_and_clear(sql, name, binds, prepare: false)
+          if preventing_writes? && write_query?(sql)
+            raise ActiveRecord::ReadOnlyError, "Write query attempted while in readonly mode: #{sql}"
+          end
+
           if without_prepared_statement?(binds)
             result = exec_no_cache(sql, name, [])
           elsif !prepare
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
index dcad230335..0b77dc7bc9 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
@@ -209,7 +209,7 @@ module ActiveRecord
       # DATABASE STATEMENTS ======================================
       #++
 
-      READ_QUERY = ActiveRecord::ConnectionAdapters::AbstractAdapter.build_read_query_regexp(:select) # :nodoc:
+      READ_QUERY = ActiveRecord::ConnectionAdapters::AbstractAdapter.build_read_query_regexp(:select, :pragma) # :nodoc:
       private_constant :READ_QUERY
 
       def write_query?(sql) # :nodoc:
@@ -222,6 +222,10 @@ module ActiveRecord
       end
 
       def exec_query(sql, name = nil, binds = [], prepare: false)
+        if preventing_writes? && write_query?(sql)
+          raise ActiveRecord::ReadOnlyError, "Write query attempted while in readonly mode: #{sql}"
+        end
+
         materialize_transactions
 
         type_casted_binds = type_casted_binds(binds)