mysql - how to select on same table twice In one query or round-trip? -


ok here code-snipet of have tried:

    private static void checkforchanges(mysqlconnection connection)     {         datetime hair = datetime.parse(smartstyledataset.tables["hair"].compute("max(lastupdated)", null).tostring());         datetime cloths = datetime.parse(smartstyledataset.tables["cloths"].compute("max(lastupdated)", null).tostring());         datetime accessories = datetime.parse(smartstyledataset.tables["accessories"].compute("max(lastupdated)", null).tostring());         datetime cosmetics = datetime.parse(smartstyledataset.tables["cosmetics"].compute("max(lastupdated)", null).tostring());          list<string>[] newrows = { new list<string>(), new list<string>(), new list<string>(), new list<string>() };             using (var command = connection.createcommand())         {             connection.open();             command.commandtext =                   "select * "                 + "from smartstyle.table_changes_logger "                 + "where  updated > @accessories , table = 'accessories' ; "                 + "select * "                 + "from smartstyle.table_changes_logger "                 + "where  updated > @cosmetics , table = 'cosmetics' ; "                 + "select * "                 + "from smartstyle.table_changes_logger "                 + "where  updated > @cloths , table = 'cloths' ; "                 + "select * "                 + "from smartstyle.table_changes_logger "                 + "where  updated > @hair , table = 'hair'";              command.parameters.add("@cloths", mysql.data.mysqlclient.mysqldbtype.timestamp).value = cloths.tostring("yyyy-mm-dd hh:mm:ss");             command.parameters.add("@hair", mysql.data.mysqlclient.mysqldbtype.timestamp).value = hair.tostring("yyyy-mm-dd hh:mm:ss");             command.parameters.add("@accessories", mysql.data.mysqlclient.mysqldbtype.timestamp).value = accessories.tostring("yyyy-mm-dd hh:mm:ss");             command.parameters.add("@cosmetics", mysql.data.mysqlclient.mysqldbtype.timestamp).value = cosmetics.tostring("yyyy-mm-dd hh:mm:ss");              using (var reader = command.executereader())             {                                 {                     while (reader.read())                     {                         newrows[0].add(reader.getstring(1));                         newrows[1].add(reader.getstring(2));                         newrows[2].add(reader.getstring(3));                         newrows[3].add(reader.getstring(4));                     }                  } while (reader.nextresult());              }         }  }

but doesn't work following generic error mysql dont understand you have error in sql syntax; check manual corresponds mysql server version right syntax use near 'table = 'accessories' ; select * smartstyle.table_changes_logger upd' @ line 1

you need escape reserved words in mysql table backticks.

select *  smartstyle.table_changes_logger   updated > @accessories  , `table` = 'accessories'

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