mysql_store_result hat gefehlt.
Versuche es so:
public OnPlayerCarsLoad(playerid)
{
new query[128];
format(query,sizeof(query),"SELECT * FROM autos WHERE besitzer='%i'",PlayerInfo[playerid][pMySQLID]);
mysql_query(query);
printf("query = %s", query);
mysql_store_result();
SendClientMessage(playerid,COLOR_RED,"Bis hier geht es");
new num_rows = mysql_num_rows();
printf("%i num rows",num_rows);
for(new i=0; i<num_rows; i++)
{
new id=getFreeCarID();
SendClientMessage(playerid,COLOR_RED,"Bis hier geht es auch");
cInfo[i][carmodel] = mysql_GetIntByInt("autos","model","besitzer",PlayerInfo[playerid][pMySQLID]);
cInfo[i][besitzer] = mysql_GetIntByInt("autos","besitzer","besitzer",PlayerInfo[playerid][pMySQLID]);
cInfo[i][c_x] = mysql_GetFloatByInt("autos","x","besitzer",PlayerInfo[playerid][pMySQLID]);
cInfo[i][c_y] = mysql_GetFloatByInt("autos","y","besitzer",PlayerInfo[playerid][pMySQLID]);
cInfo[i][c_z] = mysql_GetFloatByInt("autos","z","besitzer",PlayerInfo[playerid][pMySQLID]);
cInfo[i][c_r] = mysql_GetFloatByInt("autos","r","besitzer",PlayerInfo[playerid][pMySQLID]);
cInfo[i][db_id] = mysql_GetIntByInt("autos","id","besitzer",PlayerInfo[playerid][pMySQLID]);
cInfo[i][id_x]=CreateVehicle(cInfo[i][carmodel],cInfo[i][c_x],cInfo[i][c_y],cInfo[i][c_z],cInfo[i][c_r],-1,-1,-1);
}
mysql_free_result();
return 1;
}