Fixed mysql error

lib/blazer/adapters/sql_adapter.rb

@@ -97,6 +97,11 @@ module Blazer
         connection_model.connection.select_all(statement)
       end
 
+      # seperate from select_all to prevent mysql error
+      def execute(statement)
+        connection_model.connection.execute(statement)
+      end
+
       def postgresql?
         ["PostgreSQL", "PostGIS"].include?(adapter_name)
       end
@@ -120,9 +125,9 @@ module Blazer
 
       def set_timeout(timeout)
         if postgresql? || redshift?
-          select_all("SET #{use_transaction? ? "LOCAL " : ""}statement_timeout = #{timeout.to_i * 1000}")
+          execute("SET #{use_transaction? ? "LOCAL " : ""}statement_timeout = #{timeout.to_i * 1000}")
         elsif mysql?
-          select_all("SET max_execution_time = #{timeout.to_i * 1000}")
+          execute("SET max_execution_time = #{timeout.to_i * 1000}")
         else
           raise Blazer::TimeoutNotSupported, "Timeout not supported for #{adapter_name} adapter"
         end