是国内比较流的时序库之一，支持群集并且免费，在.NET中资料比较少，这篇文章主要介绍SqlSugar ORM来操作TDengine

优点：

1、SqlSugar支持ADO.NET操作来实现TDengine，并且支持了常用的时间函数、支持联表、分页和批量插入和删等操作

2、使用了原生连接（非http连接 ）保证了TDengine性能

Host=localhost;Port=6030;Username=root;Password=taosdata;Database=power

当前程序需要安装Sdk才能连接数据库

https://docs.taosdata.com/connector

下面是NUGET安装

SqlSugar.TDengineCore
SqlSugarCore

//建库
db.Ado.ExecuteCommand("CREATE DATABASE IF NOT EXISTS power WAL_RETENTION_PERIOD 3600");

//建超级表  
db.Ado.ExecuteCommand("CREATE STABLE IF NOT EXISTS  MyTable (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (location BINARY(64), groupId INT)");

//创建子表  
db.Ado.ExecuteCommand(@"create table IF NOT EXISTS  MyTable01 using MyTable tags('California.SanFrancisco',1)");

//insert sql  
//db.Ado.ExecuteCommand(insrtSql);

//查询子表  
var dt = db.Ado.GetDataTable("select \* from MyTable01");

//查询超级表  
var dt2 = db.Ado.GetDataTable("select \* from MyTable");

var list2 = db.Queryable().Where(it => it.name == "测试2").ToList();
var list22 = db.Queryable().Where(it => it.voltage == 222).ToList();
var list222 = db.Queryable().Where(it => it.phase == 1.2).ToList();
var list2222 = db.Queryable().Where(it => it.isdelete == true).ToList();

//联表查询:不支持left join只能这样
var list101= db.Queryable((x, y) => x.ts == y.ts)
.Select((x,y) => new
{
xts=x.ts,
yts=y.ts
}).ToList();

//模糊查询
var list3 = db.Queryable().Where(it => it.name.Contains("a")).ToList();

//时间差函数
var list31 = db.Queryable().Select(it =>
new
{
diff = SqlFunc.DateDiff(DateType.Day, it.ts, DateTime.Now),
time=it.ts
}).ToList();

//时间加1天
var list32 = db.Queryable().Select(it =>
new
{
addTime = SqlFunc.DateAdd(it.ts,1, DateType.Day),
oldime = it.ts
}).ToList();

//自定义函数:实现时间加1天
var list33 = db.Queryable().Select(it =>
new
{
addTime =SqlFunc.MappingColumn(" `ts`+1d "),
oldime = it.ts
}).ToList();

//分页
var Count = 0;
var list4 = db.Queryable().Where(it => it.voltage == 111)
.ToPageList(1, 2, ref Count);

超级表是不能插入的，我们只插入子表

//批量插入子表
db.Insertable(GetInsertDatas()).ExecuteCommand();

//子表实体
public class MyTable02
{
[SugarColumn(IsPrimaryKey =true)]
public DateTime ts { get; set; }
public float current { get; set; }
public bool isdelete { get; set; }
public string name { get; set; }
public int voltage { get; set; }
public float phase { get; set; }
[SugarColumn(IsOnlyIgnoreInsert =true,IsOnlyIgnoreUpdate =true)]//Tags字段禁止插入
public string location { get; set; }
[SugarColumn(IsOnlyIgnoreInsert = true, IsOnlyIgnoreUpdate = true)]//Tags字段禁止插入
public int groupId { get; set; }
}

只能范围删除不能直接等于删除

var count = db.Deleteable().Where(it => it.ts>time).ExecuteCommand();

找到TDengineTests文件夹

https://github.com/DotNetNext/SqlSugar