• Dapper学习(四)之Dapper Plus的大数据量的操作


    这篇文章主要讲 Dapper Plus,它使用用来操作大数量的一些操作的。比如插入1000条,或者10000条的数据时,再使用Dapper的Execute方法,就会比较慢了。这时候,可以使用Dapper Plus中的方法进行操作,提高速度。

    主要包括下面:

    • Bulk Insert
    • Bulk Update
    • Bulk Delete
    • Bulk Merge

    使用之前,需要在Nuget中,安装 Z.Dapper.Plus 

    注意:这个组件是收费的,每个月会有一个试用版本,没有免费版本

    另外一种提高批量插入速度的方式:通过把多个插入语句通过字符串拼接使成为一个长的sql语句来实现。

    1. Bulk Insert:批量插入

    1.1 Insert Single : 使用Bulk插入单个实体

    DapperPlusManager.Entity<Customer>().Table("Customers"); 
    
    using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))
    {
        connection.BulkInsert(new List<Customer>() { new Customer() { CustomerName = "ExampleBulkInsert", ContactName = "Example Name :" +  1}});
    }

    1.2 Insert Many :插入多个实体

    DapperPlusManager.Entity<Customer>().Table("Customers"); 
    
    using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))
    {
        connection.BulkInsert(customers);
    }

    1.3 Insert with relation(One to One)

    插入一对一关系的实体

    DapperPlusManager.Entity<Supplier>().Table("Suppliers").Identity(x => x.SupplierID);
    DapperPlusManager.Entity<Product>().Table("Products").Identity(x => x.ProductID);
    
    using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))
    {    
        connection.BulkInsert(suppliers).ThenForEach(x => x.Product.SupplierID = x.SupplierID).ThenBulkInsert(x => x.Product);
    }

    1.4 Insert with relation (One to Many)

    插入一对多关系的实体

    DapperPlusManager.Entity<Supplier>().Table("Suppliers").Identity(x => x.SupplierID); 
    DapperPlusManager.Entity<Product>().Table("Products").Identity(x => x.ProductID);     
    
    using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))
    {    
        connection.BulkInsert(suppliers).ThenForEach(x => x.Products.ForEach(y => y.SupplierID =  x.SupplierID)).ThenBulkInsert(x => x.Products);
    }

    2. Bulk Update

    2.1 Update Single 和 Update Many

    DapperPlusManager.Entity<Customer>().Table("Customers"); 
    
    using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))
    {
        connection.BulkUpdate(customers);
    }

    2.2 Update with relation(One to One) 和 Update with relation(One to Many)

    更新一对一关系的实体

    DapperPlusManager.Entity<Supplier>().Table("Suppliers").Identity(x => x.SupplierID);
    DapperPlusManager.Entity<Product>().Table("Products").Identity(x => x.ProductID);
    
    using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))
    {    
        connection.BulkUpdate(suppliers, x => x.Product);
    }

    更新一对多关系的实体

    DapperPlusManager.Entity<Supplier>().Table("Suppliers").Identity(x => x.SupplierID);
    DapperPlusManager.Entity<Product>().Table("Products").Identity(x => x.ProductID);
    
    using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))
    {
        connection.BulkUpdate(suppliers, x => x.Products);
    }

    3. Bulk Delete

    3.1 Delete Single 

    删除单个实体

    DapperPlusManager.Entity<Customer>().Table("Customers").Key("CustomerID");
    
    using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))
    {
        connection.BulkDelete(connection.Query<Customer>("Select * FROM CUSTOMERS WHERE CustomerID in (53,57) ").ToList());
    }

    3.2 Delete Many

    删除多个实体

    DapperPlusManager.Entity<Customer>().Table("Customers").Key("CustomerID");
    
    using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))
    {
        connection.BulkDelete(connection.Query<Customer>("Select * FROM CUSTOMERS WHERE CustomerID in (53,57) ").ToList());
    }

    3.3 Delete with relation(One to One)

    删除一对一关系的实体

    DapperPlusManager.Entity<Supplier>().Table("Suppliers").Identity(x => x.SupplierID);
    DapperPlusManager.Entity<Product>().Table("Products").Identity(x => x.ProductID);
    
    using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))
    {
        connection.BulkDelete(suppliers.Select(x => x.Product)).BulkDelete(suppliers);
    }

    3.4 Delete with relation(One to Many)

    删除一对多关系的实体

    DapperPlusManager.Entity<Supplier>().Table("Suppliers").Identity(x => x.SupplierID);
    DapperPlusManager.Entity<Product>().Table("Products").Identity(x => x.ProductID);
    
    using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))
    {
        connection.BulkDelete(suppliers.SelectMany(x => x.Products)).BulkDelete(suppliers);
    }

    4.Bulk Merge

    4.1 Merge Single

    DapperPlusManager.Entity<Customer>().Table("Customers"); 
    
    using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))
    {
        connection.BulkMerge(new List<Customer>() { new Customer() { CustomerName = "ExampleBulkMerge", ContactName = "Example Name :" +  1}});
    }

    4.2 Merge Many

    DapperPlusManager.Entity<Customer>().Table("Customers"); 
    
    using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))
    {
        connection.BulkMerge(customers);
    }

    4.3 Merge with relation(One to One)

    DapperPlusManager.Entity<Supplier>().Table("Suppliers").Identity(x => x.SupplierID);
    DapperPlusManager.Entity<Product>().Table("Products").Identity(x => x.ProductID);
    
    using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))
    {    
        connection.BulkMerge(suppliers).ThenForEach(x => x.Product.SupplierID = x.SupplierID).ThenBulkMerge(x => x.Product);
    }

    4.4 Merge with relation(One to Many)

    DapperPlusManager.Entity<Supplier>().Table("Suppliers").Identity(x => x.SupplierID);
    DapperPlusManager.Entity<Product>().Table("Products").Identity(x => x.ProductID);
    
    using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))
    {
        connection.BulkMerge(suppliers).ThenForEach(x => x.Products.ForEach(y => y.SupplierID =  x.SupplierID)).ThenBulkMerge(x => x.Products);
    }
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  • 原文地址:https://www.cnblogs.com/Vincent-yuan/p/11521373.html
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