从数据库中删除不在平面文件中的记录

Question

I'm importing records from a text file into my DB. I have it setup to check the record that I to ensure there is not already a duplicate in the database. If there is already an entry in the database it skips that record. Now the issue I need to address is when there is not a record in the text file but there is a record in the database. I need to remove the record from the database that does not match any records in the file.

    public static void ParseComplaint(string location)
    {

        Console.WriteLine("Parsing.....");
        List<AutoMakeNoEntity> am = DBCacheHelper.GetAllMakes().ToList<AutoMakeNoEntity>();

        using (var reader = new StreamReader(location))
        {
            foreach (string line in File.ReadLines(location))
            {
                if (string.IsNullOrWhiteSpace(line))
                {
                    continue;
                }
                var tokens = line.Trim().Split(new char[] { '\t' });

                if (am.Any(c => c.MakeName == tokens[3]))
                {
                    using (RecallsContext context = new RecallsContext())
                    {
                        string tmp = tokens[0];
                        if (!context.complaints.Any(c => c.CMPLID == tmp))
                        {

                            var recalls = new Complaints();

                            recalls.CMPLID = tokens[0];
                            recalls.ODINO = tokens[1];
                            recalls.MFR_NAME = tokens[2];
                            recalls.MAKETXT = tokens[3];
                            recalls.MODELTXT = tokens[4];
                            recalls.YEARTXT = tokens[5];
                            recalls.CRASH = tokens[6];
                            recalls.FAILDATE = tokens[7];
                            recalls.FIRE = tokens[8];
                            recalls.INJURED = tokens[9];
                            recalls.DEATHS = tokens[10];
                            recalls.COMPDESC = tokens[11];
                            recalls.CITY = tokens[12];
                            recalls.STATE = tokens[13];
                            recalls.VIN = tokens[14];
                            recalls.DATEA = tokens[15];
                            recalls.LDATE = tokens[16];
                            recalls.MILES = tokens[17];
                            recalls.OCCURENCES = tokens[18];
                            recalls.CDESCR = tokens[19];
                            recalls.CMPL_TYPE = tokens[20];
                            recalls.POLICE_RPT_YN = tokens[21];
                            recalls.PURCH_DT = tokens[22];
                            recalls.ORIG_OWNER_YN = tokens[23];
                            recalls.ANTI_BRAKES_YN = tokens[24];
                            recalls.CRUISE_CONT_YN = tokens[25];
                            recalls.NUM_CYLS = tokens[26];
                            recalls.DRIVE_TRAIN = tokens[27];
                            recalls.FUEL_SYS = tokens[28];
                            recalls.FUEL_TYPE = tokens[29];
                            recalls.TRANS_TYPE = tokens[30];
                            recalls.VEH_SPEED = tokens[31];
                            recalls.DOT = tokens[32];
                            recalls.TIRE_SIZE = tokens[33];
                            recalls.LOC_OF_TIRE = tokens[34];
                            recalls.TIRE_FAIL_TYPE = tokens[35];
                            recalls.ORIG_EQUIP_YN = tokens[36];
                            recalls.MANUF_DT = tokens[37];
                            recalls.SEAT_TYPE = tokens[38];
                            recalls.RESTRAINT_TYPE = tokens[39];
                            recalls.DEALER_NAME = tokens[40];
                            recalls.DEALER_TEL = tokens[41];
                            recalls.DEALER_CITY = tokens[42];
                            recalls.DEALER_STATE = tokens[43];
                            recalls.DEALER_ZIP = tokens[44];
                            recalls.PROD_TYPE = tokens[45];
                            if (tokens.Length == 47)
                            {
                                recalls.REPAIRED_YN = tokens[46];
                            }

                            context.complaints.Add(recalls);
                            context.SaveChanges();
                            recalls.Dispose();
                        }

                    }
                }
            }
        }
    }

Answer 1

I need to remove the record from the database that does not match any records in the file.

If you want the database to match the contents of the text file, why don't you simply empty it first?