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newlife.xcode跨库跨表数据查询

本文主要是介绍newlife.xcode跨库跨表数据查询,对大家解决编程问题具有一定的参考价值,需要的程序猿们随着小编来一起学习吧!

1、在model.biz的静态构造类中添加分库分表策略

static History()
        {
            

            // 添加分库分表策略
            
            Meta.ShardPolicy = new TimeShardPolicy(nameof(CreateTime), Meta.Factory)
            {
                ConnPolicy = "HDB_{1:yyMM}",
                TablePolicy = "History_{1:yyMMdd}",
                Step = TimeSpan.FromDays(1), 

            };

            Meta.Modules.Add<UserModule>();
            Meta.Modules.Add<TimeModule>();
            Meta.Modules.Add<IPModule>();
        }

2、构造测试数据

static void TestByDate()
{
    XTrace.WriteLine("按时间分表分库,每月一个库,每天一张表");

    // 预先准备好各个库的连接字符串,动态增加,也可以在配置文件写好
    var start = DateTime.Today;
    for (var i = 0; i < 12; i++)
    {
        var dt = new DateTime(start.Year, i + 1, 1);
        var connName = $"HDB_{dt:yyMM}";
        DAL.AddConnStr(connName, $"data source=timeData\\{connName}.db", null, "sqlite");
    }

    // 每月一个库,每天一张表
    start = new DateTime(start.Year, 1, 1);
    for (var i = 0; i < 365; i++)
    {
        var dt = start.AddDays(i);
        History.Meta.ConnName = $"HDB_{dt:yyMM}";
        History.Meta.TableName = $"History_{dt:yyMMdd}";

        // 插入一批数据
        var list = new List<History>();
        for (var n = 0; n < 1000; n++)
        {
            var entity = new History
            {
                Category = "交易",
                Action = "转账",
                CreateUserID = 1234,
                CreateTime = dt,
                Remark = $"[{Rand.NextString(6)}]向[{Rand.NextString(6)}]转账[¥{Rand.Next(1_000_000) / 100d}]"
            };

            list.Add(entity);
        }

        // 批量插入。两种写法等价
        //list.BatchInsert();
        list.Insert(true);
    }
}

3、测试跨库跨表数据查询

static void Search()
{

    var start = DateTime.Today;

    for (var i = 0; i < 12; i++)
    {
        var dt = new DateTime(start.Year, i + 1, 1);
        var connName = $"HDB_{dt:yyMM}";
        DAL.AddConnStr(connName, $"data source=timeData\\{connName}.db", null, "sqlite");
    }


    //跨表
    //var dt1 = new DateTime(start.Year, 1, 1);
    //var dt2 = new DateTime(start.Year, 1, 10);
    //跨库
    var dt1 = Convert.ToDateTime("2021-1-31");
    var dt2 = Convert.ToDateTime("2021-3-1");
    var exp = new WhereExpression();

    exp &= History._.CreateTime.Between(dt1, dt2);


    PageParameter pageParameter = new PageParameter
    {
        PageSize = 3000,
        PageIndex = 1,
        RetrieveTotalCount = true
    };
    var list = History.FindAll(exp, pageParameter).OrderBy(x=>x.CreateTime).OrderBy(x=>x.ID);
    var allcount = pageParameter.TotalCount;
    var re = Newtonsoft.Json.JsonConvert.SerializeObject(list.OrderBy(x=>x.ID));
    Console.WriteLine(re);
    Console.WriteLine(allcount);



}

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