1 files changed, 15 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
index b41bf2fc66..44c6e99112 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
@@ -209,12 +209,23 @@ module ActiveRecord
       # DATABASE STATEMENTS ======================================
       #++
 
+      READ_QUERY = ActiveRecord::ConnectionAdapters::AbstractAdapter.build_read_query_regexp(:begin, :commit, :explain, :select, :pragma, :release, :savepoint, :rollback) # :nodoc:
+      private_constant :READ_QUERY
+
+      def write_query?(sql) # :nodoc:
+        !READ_QUERY.match?(sql)
+      end
+
       def explain(arel, binds = [])
         sql = "EXPLAIN QUERY PLAN #{to_sql(arel, binds)}"
         SQLite3::ExplainPrettyPrinter.new.pp(exec_query(sql, "EXPLAIN", []))
       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)
@@ -257,6 +268,10 @@ module ActiveRecord
       end
 
       def execute(sql, name = nil) #:nodoc:
+        if preventing_writes? && write_query?(sql)
+          raise ActiveRecord::ReadOnlyError, "Write query attempted while in readonly mode: #{sql}"
+        end
+
         materialize_transactions
 
         log(sql, name) do