ado.net

问题 I am using dapper to do some oracle access. I have a scenario where I have to have an output parameter with a type of OracleDbType.Clob. As I am using dapper and thus using the base DbType enumeration I am using the DbType.Object enum as suggested here http://docs.oracle.com/html/B14164_01/featOraCommand.htm to stand in for OracleDbType.Clob. However, this sets the command parameter (deep down in dapper) to be of DbType object and oracle type Blob (as the DbConnection providers a concrete

问题 I have an older application that I wrote where I used Microsoft.Practices.EnterpriseLibrary.Data to get data from the DB. I have recently upgraded to .NET 4.5 and wanted to advantage of await/async . I do not see any methods ending in "Async" as per the naming standard, even in the most recent version of the package. Is it possible to use await/async with this ADO .NET library without manually making it asynchronous? 回答1: I'm using an older version of the EL that offers Begin* / End* methods,

问题 My Windows Forms application uses a strongly typed dataset created using the designer in Visual Studio. At runtime I would like to be able to select either the live or test database. What is the best way to programmatically set the connection string for the dataset at runtime? 回答1: Connection property in TableAdapters is defined as internal . internal global::System.Data.SqlClient.SqlConnection Connection So in case your TypedDataset is not in the same assembly as your main windows forms app,

问题 We are using an Informix database, and are connecting to it from .NET sucessfully using ODBC. The connection string we are using is; DRIVER={IBM INFORMIX ODBC RIVER}; UID=username; PWD=password; DATABASE=our_database; HOST=devsrv01; SERVER=devsrv01_tcp; SERVICE=ids9tcp2; PROTOCOL=onsoctcp; CLIENT_LOCALE=en_US.CP1252; DB_LOCALE=en_US.819; We want to change from ODBC and use IBM's SDK and libraries as outlined on their site. The code we are using is; string ConnectionString = "Database=our

问题 We are using an Informix database, and are connecting to it from .NET sucessfully using ODBC. The connection string we are using is; DRIVER={IBM INFORMIX ODBC RIVER}; UID=username; PWD=password; DATABASE=our_database; HOST=devsrv01; SERVER=devsrv01_tcp; SERVICE=ids9tcp2; PROTOCOL=onsoctcp; CLIENT_LOCALE=en_US.CP1252; DB_LOCALE=en_US.819; We want to change from ODBC and use IBM's SDK and libraries as outlined on their site. The code we are using is; string ConnectionString = "Database=our

问题 I have a web forms app that will display a list of records in a GridView and by checking multiple checkboxes you can mass delete the records. The code itself is straightforward: protected void btnDelete_Click(object sender, EventArgs e) { int i = 0; try { foreach (GridViewRow row in GridView1.Rows) { CheckBox cb = (CheckBox)row.FindControl("ID"); if (cb != null && cb.Checked) { int profileID = Convert.ToInt32(GridView1.DataKeys[row.RowIndex].Value); Profile profile = new Profile(profileID); /

问题 I have a web forms app that will display a list of records in a GridView and by checking multiple checkboxes you can mass delete the records. The code itself is straightforward: protected void btnDelete_Click(object sender, EventArgs e) { int i = 0; try { foreach (GridViewRow row in GridView1.Rows) { CheckBox cb = (CheckBox)row.FindControl("ID"); if (cb != null && cb.Checked) { int profileID = Convert.ToInt32(GridView1.DataKeys[row.RowIndex].Value); Profile profile = new Profile(profileID); /

问题 I'm exploring query notifications with the SQLDependency class. Building a simple working example is easy, but I feel like I'm missing something. Once I step past a simple one-table/one-dependency example I'm left wondering how can I figure out which dependency triggered my callback? I'm having a bit of trouble explaining, so I included the simple example below. When AChange() is called I cannot look at the sql inside the dependency, and i don't have a reference to the associated cache object

问题 I have a stored procedure that returns multiple tables. How can I execute and read both tables? I have something like this: SqlConnection conn = new SqlConnection(CONNECTION_STRING); SqlCommand cmd = new SqlCommand("sp_mult_tables",conn); cmd.CommandType = CommandType.StoredProcedure); IDataReader rdr = cmd.ExecuteReader(); I'm not sure how to read it...whats the best way to handle this type of query, I am guessing I should read the data into a DataSet? How is the best way to do this? Thanks.

问题 during beta testing we discovered connection pooling error messages . Therefore I have been going through the code and closing down the SqlDataReader objects wherever they have been left unclosed. What I need to know is how to close a datareader (or if there is a need at all to close) that is specified in the SelectStatement attribute of the SqlDataSource or ObjectDataSource tags. Could there be connection leak if they are not handled? Thanks in advance ! 回答1: I tend to use the "using"