Sql Sugar 使用

• sql sugar orm文档地址： SqlSugar ORM 5.X 官网 、文档、教程 - SqlSugar 5x - .NET果糖网 (donet5.com)

• sql sugar 基本用法大全，来自博主 @天才卧龙 ：https://www.cnblogs.com/chenwolong/p/13858384.html

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.net 5.0 + sqlsugarcore(5.0.4.2)

一、SqlSugarScope 、SqlSugarClient 、SqlConnection区别

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一、区别

scope是对client的进一步封装，为了支持线程安全，并且在不同上下文中自动new出一个client，在编写代码时不需要考虑他线程是否安全

二、总结

他们3者的关系应该是这样的：

SqlSugarScope 底层+自动释放+上下文安全
SqlSugarClient 底层+自动释放控制
SqlConnection  底层

三、引申

1.什么是上下文?

异步情况： 在同一串await 中是一个上下文
同步情况： 在同一个线程是同一个上下文
同一个SqlSugarScope做到了在同一个上下文共享一个对象，不同上下文自动去NEW

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二、Code First、DB First

一、code first

1.创建方式

/// <summary>
/// 代码优先
/// </summary>
public static void CodeFirstShow()
{
    ConnectionConfig config = new ConnectionConfig()
    {
        ConnectionString = "",
        DbType = DbType.SqlServer,
        IsAutoCloseConnection = true,
    };

    using (SqlSugarClient db = new SqlSugarClient(config))
    {
        //如果不存在创建数据库
        db.DbMaintenance.CreateDatabase();
        Type[] types = Assembly
            .LoadFrom("类库")
            .GetTypes()
            .ToArray();

        db.CodeFirst.SetStringDefaultLength(200).InitTables(types);
    }
}

2.code first 上下文创建数据库

public class SugarDbContext
{
    public SqlSugarClient Db;
    public SugarDbContext()
    {

        Db = new SqlSugarClient(new ConnectionConfig()
                                {
                                    ConnectionString = "server=.;database=StudentDb;uid=cnpy;pwd=cnpy1314;",
                                    DbType = DbType.SqlServer,//设置数据库类型
                                    IsAutoCloseConnection = true,//自动释放数据库，如果存在事务，在事务结束之后释放。
                                    InitKeyType = InitKeyType.Attribute//从实体特性中读取主键自增列信息
                                });

        Db.Aop.OnLogExecuting = (sql, pars) =>
        {
            Console.WriteLine(sql + "\r\n" + Db.Utilities.SerializeObject
                              (pars.ToDictionary(it => it.ParameterName, it => it.Value)));
            Console.WriteLine();
        };
    }
    public void CreateTable(bool Backup = false, int StringDefaultLength = 50, params Type[] types)
    {
        Db.CodeFirst.SetStringDefaultLength(StringDefaultLength);
        Db.DbMaintenance.CreateDatabase();

        if (Backup)
        {
            Db.CodeFirst.BackupTable().InitTables(types);
        }
        else
        {
            Db.CodeFirst.InitTables(types);
        }
    }

    public SimpleClient<Students> studentDb { get { return new SimpleClient<Students>(Db); } }
    public SimpleClient<Schools> schoolDb { get { return new SimpleClient<Schools>(Db); } }

}

二、DB First

1.创建方式

/// <summary>
/// 数据库优先
/// </summary>
public static void DbFirstShow() {
    ConnectionConfig config = new ConnectionConfig() {
        ConnectionString="",
        DbType=DbType.SqlServer,
        IsAutoCloseConnection=true,
    };
    using (SqlSugarClient db=new SqlSugarClient(config))
    {

        //IsCreateAttribute:代表生成sqlsugar特性.
        db.DbFirst
            .IsCreateAttribute()
            .CreateClassFile("类库所在文件夹","类库名称");
    }
}

数据表

! 联表查询

联表查询：

            SqlSugarClient Db = new SqlSugarClient(new ConnectionConfig() {
                ConnectionString = "Data Source=.;Initial Catalog=CoreShop;User ID=sa;Password=sa123;",
                DbType = DbType.SqlServer,
                IsAutoCloseConnection = true
            });

            Db.Aop.OnLogExecuting = (sql, pars) =>
            {
                Console.WriteLine(sql);//输出sql,查看执行sql 性能无影响

                //5.0.8.2 获取无参数化SQL 对性能有影响，特别大的SQL参数多的，调试使用
                //UtilMethods.GetSqlString(DbType.SqlServer,sql,pars)
            };

            var cart = Db.Queryable<CoreCmsCart>().ToList();

          var goods=  Db.Queryable<CoreCmsProducts, CoreCmsGoods, CoreCmsCart>((o, i, c) => new JoinQueryInfos(
              JoinType.Left, o.goodsId == i.id, //左连接 左链接 左联
              JoinType.Left, o.id == c.productId))
                .Select((o, i, c) => new { name=i.name, price = o.price })
                .ToList();

//实战应用：
var view = new object ();

            var items = _coreCmsGoodsServices.QueryMuch<CoreCmsProducts, CoreCmsGoods, CoreCmsCart, GoodsDetailsVM>(
                  (p, g, c) => new object[] { JoinType.Left, p.goodsId == g.id, JoinType.Left, p.id == c.productId },
        (p, g, c) => new GoodsDetailsVM { Id = c.id, name = g.name, price = p.price }
                  );

三、项目使用

1、启动sqlsugar服务

/// <summary>
/// SqlSugar 启动服务
/// </summary>
public static class SqlSugarSetup
{

    public static void AddSqlSugarSetup(this IServiceCollection services)
    {
        if (services == null) throw new ArgumentNullException(nameof(services));

        //注入 ORM
        SugarIocServices.AddSqlSugar(new IocConfig()
                                     {
                                         //数据库连接
                                         ConnectionString = AppSettingsConstVars.DbSqlConnection,
                                         //判断数据库类型
                                         DbType = AppSettingsConstVars.DbDbType == IocDbType.MySql.ToString() ? IocDbType.MySql : IocDbType.SqlServer,
                                         //是否开启自动关闭数据库连接-//不设成true要手动close
                                         IsAutoCloseConnection = true,
                                     });

        //设置参数
        services.ConfigurationSugar(db =>
                                    {
                                        db.CurrentConnectionConfig.InitKeyType = InitKeyType.Attribute;
                                        //db.CurrentConnectionConfig.ConfigureExternalServices = new ConfigureExternalServices()
                                        //{
                                        //    //判断是否开启redis设置二级缓存方式
                                        //    DataInfoCacheService = AppSettingsConstVars.RedisUseCache ? (ICacheService)new SqlSugarRedisCache() : new SqlSugarMemoryCache()
                                        //};

                                        //执行SQL 错误事件，可监控sql（暂时屏蔽，需要可开启）
                                        //db.Aop.OnLogExecuting = (sql, p) =>
                                        //{
                                        //    NLogUtil.WriteFileLog(NLog.LogLevel.Error, LogType.Other, "SqlSugar执行SQL错误事件打印Sql", sql);
                                        //};

                                        //执行SQL 错误事件
                                        db.Aop.OnError = (exp) =>
                                        {

                                            NLogUtil.WriteFileLog(NLog.LogLevel.Error, LogType.Other, "SqlSugar", "执行SQL错误事件", exp);
                                        };

                                        //设置更多连接参数
                                        //db.CurrentConnectionConfig.XXXX=XXXX
                                        //db.CurrentConnectionConfig.MoreSetting=new MoreSetting(){}
                                        //读写分离等都在这儿设置
                                    });

    }
}

2、注入服务

//添加数据库连接SqlSugar注入支持
services.AddSqlSugarSetup();

3.创建工作单元接口、实现 UnitOfWork

• 接口 IUnitOfWork

using SqlSugar;

public interface IUnitOfWork
{
    SqlSugarScope GetDbClient();//获取db对象
    void BeginTran();//开启事务
    void CommitTran();//提交事务
    void RollbackTran();//回滚是u我
}

• 实现 UnitOfWork

点击查看代码

public class UnitOfWork : IUnitOfWork
{
    private readonly ISqlSugarClient _sqlSugarClient;

    public UnitOfWork()
    {
        _sqlSugarClient = DbScoped.SugarScope;
    }

    /// <summary>
    ///     获取DB，保证唯一性
    /// </summary>
    /// <returns></returns>
    public SqlSugarScope GetDbClient()
    {
        // 必须要as，后边会用到切换数据库操作
        return _sqlSugarClient as SqlSugarScope;
    }

    public void BeginTran()
    {
        GetDbClient().BeginTran();
    }

    public void CommitTran()
    {
        try
        {
            GetDbClient().CommitTran(); //
        }
        catch (Exception ex)
        {
            GetDbClient().RollbackTran();
            NLogUtil.WriteFileLog(LogLevel.Error, LogType.Web, "事务提交异常", "事务提交异常", new Exception("事务提交异常", ex));
            throw;
        }
    }

    public void RollbackTran()
    {
        GetDbClient().RollbackTran();
    }
}

4、使用