C#的sqlite orm - praeclarum/sqlite-net笔记

此orm需要用到sqlite3的运行库,从这里下载:https://www.sqlite.org/download.html

安装source: https://github.com/praeclarum/sqlite-net/blob/master/src/SQLite.cs

应用:

1、建立基础类

class DBConfig
    {
        public SQLiteConnection connection { get; set; }
        public DBConfig()
        {
            var databasePath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "lpm.db");
            connection = new SQLiteConnection(databasePath);
        }
        ~DBConfig()
        {
            connection.Close();
        }
    }
## 1、建立/连接s

2、应用

建立数据库、表

private DBConfig dBConfig;
        private SQLiteConnection conn;
        public PLMDB()
        {
            this.dBConfig = new DBConfig();
            conn = dBConfig.connection;
            conn.CreateTable<T96PDLogTable>();
            conn.CreateTable<Keyvalue>();
        }

统计查询

public long UnSubmitCount()
{
  return  conn.ExecuteScalar<long>("select count(*) from T96PDLogTable where uploadTime is null");
}

查询记录

public List<T96PDLogTable> getUnunLoad(int limitNum)
{
    IEnumerable <T96PDLogTable> r = conn.Query<T96PDLogTable>("select * from T96PDLogTable where uploadTime is null order by RecSEQ limit " + limitNum);            
    return r.ToList();
}

参数化

public int removeOldData(int keepDays)
        {
            DateTime utc = Utils.toUTC(DateTime.Now.AddDays(-keepDays));
            long tm = Utils.CurrentMillis(utc);
            return conn.Execute("delete from T96PDLogTable where uploadTime is not null  and f96_create_dt<?", tm);
        }

条件查询Where
public bool markToUploaded(String recseq)
{
var query = conn.Table().Where(v => v.RecSEQ.Equals(recseq));

}

批量增加

public bool addT96(List<T96PDLogTable> t96List)
        {
            try
            {
                return conn.InsertAll(t96List, true) == t96List.Count;
            }
            catch (Exception e)
            {
                if  (!e.Message.Contains("UNIQUE constraint"))
                {
                    throw e;
                }
                return true;
            }
        }        

批量修改

 public bool markToUploaded(List<T96PDLogTable> t96List)
        {
            t96List.ForEach(c => c.uploadTime = DateTime.Now.ToString());
            return conn.UpdateAll(t96List, true) == t96List.Count;
        }
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