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Use Dapper's QueryMultiple method to execute multiple SQL statements at once and return multiple result sets. The code is as follows

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Configuration;using Dapper;using System.Data;using System.Data.SqlClient;using DapperAppQueryMultiple.Model;namespace DapperAppQueryMultiple{ class Program { static void Main(string[] args) { //define connection string string conn = ConfigurationManager.ConnectionStrings["AppConnection"].ConnectionString; using (IDbConnection connection = new SqlConnection(conn)) { var sql = @"SELECT * FROM Users WHERE UserId=@UserId; SELECT * FROM Product WHERE ProductId=@ProductId"; var queryMulti = connection.QueryMultiple(sql, new { UserId = 1, ProductId=3 }); //Note: Read must be obtained in the order of returning the tables above, such as the Users table queried first, so Read must first return the Users table, otherwise no data will be returned. var users = queryMulti.Read(); var products = queryMulti.Read(); Console.WriteLine("**** Product Information ****"); //loop through output products.AsList().ForEach(p => { Console.WriteLine("Product Name:"+p.ProductName+"Price:"+p.Price); }); Console.WriteLine("**** Product Information ****"); Console.WriteLine("**** User Info ****"); users.AsList().ForEach(p => { Console.WriteLine("User Name:"+p.UserName+"Email:"+p.Email+"Address:"+p.Address); }); Console.WriteLine("**** User Info ****"); } Console.ReadKey(); } }}

Program Run Results:

Note: Read must be obtained according to the order of the tables returned above, such as the Users table queried first, so Read must first return the Users table, otherwise no data will be returned. The T generic class in Read does not have to be the same as the database table name. The T generic class in the above code is User, and the database table name is Users.

The following code demonstrates the return order differently:

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Configuration;using Dapper;using System.Data;using System.Data.SqlClient;using DapperAppQueryMultiple.Model;namespace DapperAppQueryMultiple{ class Program { static void Main(string[] args) { //Define connection string string conn = ConfigurationManager.ConnectionStrings["AppConnection"].ConnectionString; using (IDbConnection connection = new SqlConnection(conn)) { var sql = @"SELECT * FROM Users WHERE UserId=@UserId; SELECT * FROM Product WHERE ProductId=@ProductId"; var queryMulti = connection.QueryMultiple(sql, new { UserId = 1, ProductId=3 }); //Return query data of Product table first var products = queryMulti.Read(); var users = queryMulti.Read(); Console.WriteLine("**** Product Information ****"); //loop through output products.AsList().ForEach(p => { Console.WriteLine("Product Name:"+p.ProductName+"Price:"+p.Price); }); Console.WriteLine("**** Product Information ****"); Console.WriteLine("**** User Info ****"); users.AsList().ForEach(p => { Console.WriteLine("User Name:"+p.UserName+"Email:"+p.Email+"Address:"+p.Address); }); Console.WriteLine("**** User Info ****"); } Console.ReadKey(); } }}

The above code only modifies the data returned to the table, and the program runs as follows:

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