c# - Input string was not in a correct format using MySQLDataAdapter -

i have looked @ number of questions/answers here, none of them seem help

i have below method select data mysql database

i have highlighted line error happens on.

the string sql being passed select * tbldtcategory;

opendbconnection(dbconn)) open connection , return problems it, runs fine

i can't understand why i'm getting error, looking @ adapter seems ok, , i'm not trying add or update database can't mismatched type...

    public datatable select(string sql)     {                     mysqlconnection dbconn = new mysqlconnection(dbconnection);          mysqldataadapter adapter = new mysqldataadapter();           datatable rettable = new datatable();           if (opendbconnection(dbconn))         {             try             {                 adapter.selectcommand = new mysqlcommand(sql, dbconn);                 adapter.fill(rettable); // error here             }             catch (exception ex)             {                 messagebox.show(ex.message);                  return null;             }                         {                 closedbconnection(dbconn);             }         }         else             return null;          return rettable;     } 

image show must have connected database

image show should returned

**note record: 3-newcat-1 added app changing select statement insert statement - no problems (!)

stacktrace:

   @ system.number.stringtonumber(string str, numberstyles options, numberbuffer& number, numberformatinfo info, boolean parsedecimal)    @ system.number.parseint32(string s, numberstyles style, numberformatinfo info)    @ system.int32.parse(string s, iformatprovider provider)    @ mysql.data.types.mysqlint32.mysql.data.types.imysqlvalue.readvalue(mysqlpacket packet, int64 length, boolean nullval)    @ mysql.data.mysqlclient.nativedriver.readcolumnvalue(int32 index, mysqlfield field, imysqlvalue valobject)    @ mysql.data.mysqlclient.driver.readcolumnvalue(int32 index, mysqlfield field, imysqlvalue value)    @ mysql.data.mysqlclient.resultset.get_item(int32 index)    @ mysql.data.mysqlclient.mysqldatareader.getfieldvalue(int32 index, boolean checknull)    @ mysql.data.mysqlclient.mysqldatareader.getvalue(int32 i)    @ mysql.data.mysqlclient.mysqldatareader.getvalues(object[] values)    @ system.data.providerbase.datareadercontainer.commonlanguagesubsetdatareader.getvalues(object[] values)    @ system.data.providerbase.schemamapping.loaddatarow()    @ system.data.common.dataadapter.fillloaddatarow(schemamapping mapping)    @ system.data.common.dataadapter.fillfromreader(dataset dataset, datatable datatable, string srctable, datareadercontainer datareader, int32 startrecord, int32 maxrecords, datacolumn parentchaptercolumn, object parentchaptervalue)    @ system.data.common.dataadapter.fill(datatable[] datatables, idatareader datareader, int32 startrecord, int32 maxrecords)    @ system.data.common.dbdataadapter.fillinternal(dataset dataset, datatable[] datatables, int32 startrecord, int32 maxrecords, string srctable, idbcommand command, commandbehavior behavior)    @ system.data.common.dbdataadapter.fill(datatable[] datatables, int32 startrecord, int32 maxrecords, idbcommand command, commandbehavior behavior)    @ system.data.common.dbdataadapter.fill(datatable datatable)    @ downtime_aquisition_administrator.mysqlserver.select(string sql) in d:\vs2012\projects\downtime acquisition\downtime aquisition administrator\downtime aquisition administrator\frmmain.cs:line 1996 

ok found problem - school boy error lol

went mysql server , ran setup again, chose utf-8 instead of 1 of drop down options text format, works fine

..and feel stupid :)