sqlconnection

问题 Which pattern is better for SqlConnection object? Which is better in performance? Do you offer any other pattern? class DataAccess1 : IDisposable { private SqlConnection connection; public DataAccess1(string connectionString) { connection = new SqlConnection(connectionString); } public void Execute(string query) { using (SqlCommand command = connection.CreateCommand()) { command.CommandText = query; command.CommandType = CommandType.Text; // ... command.Connection.Open(); command

问题 I have a distributed transaction context using ServiceDomain . Inside it, I open an SQL connection with connection string specifying Enlist=false , so that it is not automatically enlisted in the transaction. Then, if I manually enlist the connection in the distributed transaction using EnlistDistributedTransaction , the connection does not get closed, which can end in an InvalidOperationException with: Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool.

问题 What is the difference between using connection.OpenAsync() and connection.Open() when using dapper's QueryAsync method. Async: public async Task<IList<Product>> GetListAsync() { using (var connection = new SqlConnection(_connectionString)) { StringBuilder sql = new StringBuilder(); sql.AppendLine("SELECT Id, Name "); sql.AppendLine("FROM Product "); await connection.OpenAsync(); var tickets = await connection.QueryAsync<Ticket>(sql.ToString()); return tickets.ToList(); } } Not Async: public

问题 I've come from Java experience and am trying to start with C#. I've read SqlConnection SqlCommand SqlDataReader IDisposable and I can understand that the best practice to connecting to a DB is wrapping SqlConnection , SqlCommand and SqlDataReader in their own using block. But in Java we use to encapsulate the connection into a factory method, create it only once, and reuse it for all queries, even multithreaded ones. Only statements and result sets are created for each query and closed ASAP.

问题 I've come from Java experience and am trying to start with C#. I've read SqlConnection SqlCommand SqlDataReader IDisposable and I can understand that the best practice to connecting to a DB is wrapping SqlConnection , SqlCommand and SqlDataReader in their own using block. But in Java we use to encapsulate the connection into a factory method, create it only once, and reuse it for all queries, even multithreaded ones. Only statements and result sets are created for each query and closed ASAP.

问题 I know this has been asked before, and I tried to implement the solution, but I just get exception errors when I call ps->executeUpdate(). Has anyone got an explicit example? 回答1: Sorry Matthew - I assumed the previous answer to this question (by elrohin). Maybe I should have replied to that. Anyway heres the code he suggested: class DataBuf : public streambuf { public: DataBuf(char * d, size_t s) { setg(d, d, d + s); } }; // prepare sql update statement etc. and set the data pointer string*

问题 I'm using Azure Functions with queue triggers for part of our workload. The specific function queries the database and this creates problems with scaling since the large concurrent number of function instances pinging the db results in maximum allowed number of Azrue DB connections being hit constantly. This article https://docs.microsoft.com/en-us/azure/azure-functions/manage-connections lists HttpClient as one of those resources that should be made static. Should database access also be

问题 I am fairly new to powerbuilder 12.5 and i cant find much tutorials on database management on SQL 2008. I need to connect to it via code like in VB.NET vs2008 Dim con As New SqlConnection Con.connectionstring = "Data Source=servername;Initial Catalog=user;Integrated Security=True" I need to select, insert, update and delete data... Any help on code samples 回答1: Datawindows Most database work with PB is done using datawindows. After you create a new datawindow, you set up your select statement

问题 This one has me stumped. I'm not even trying to connect to a database. When this code gets to the line where I instantiate a new SqlConnection object, it just hangs there, not throwing an exception or anything. I've tried compiling it for 2.0. 3.5 and 4.0, and they all hang. Of course it works on my machine and yours, too. But I'm trying to run this code on a Windows Server 2008 x64 server, and it won't budge. // example.cs using System; using System.Data; using System.Data.SqlClient; public

问题 What is the the best practice for SQL connections? Currently I am using the following: using (SqlConnection sqlConn = new SqlConnection(CONNECTIONSTRING)) { sqlConn.Open(); // DB CODE GOES HERE } I have read that this is a very effective way of doing SQL connections. By default the SQL pooling is active, so how I understand it is that when the using code ends the SqlConnection object is closed and disposed but the actual connection to the DB is put in the SQL connection pool. Am i wrong about