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c#oracle-databasetdd

Insert blob in oracle database with C#


I have to persist a .csv in my database, but for a more testable application I prefer don't use procedures. Basically I just generate a file and the next instruction is put this in database.

Someone have some clue about best way to do this in code?


Solution

  • Here is an example to insert blob data in oracle using c# and procedures (you said prefer that means you may).

    using System;
    using System.Data;
    using Oracle.DataAccess.Client;
    using Oracle.DataAccess.Types;
    using System.IO;
    using System.Text;
    
    //Step 1
    // Connect to database
    // Note: Modify User Id, Password, Data Source as per your database setup
    string constr = "User Id=Scott;Password=tiger;Data Source=orcl9i";
    
    OracleConnection con = new OracleConnection(constr);
    con.Open();
    Console.WriteLine("Connected to database!");
    
    // Step 2
    // Note: Modify the Source and Destination location
    // of the image as per your machine settings
    String SourceLoc  = "D:/Images/photo.jpg";
    String DestinationLoc = "D:/Images/TestImage.jpg";
    
    // provide read access to the file
    
    FileStream fs = new FileStream(SourceLoc, FileMode.Open,FileAccess.Read);
    
    // Create a byte array of file stream length
    byte[] ImageData = new byte[fs.Length];
    
    //Read block of bytes from stream into the byte array
    fs.Read(ImageData,0,System.Convert.ToInt32(fs.Length));
    
    //Close the File Stream
    fs.Close();
    
    // Step 3
    // Create Anonymous PL/SQL block string
    String block = " BEGIN " +
                   " INSERT INTO testblob (id, photo) VALUES (100, :1); " +
                   " SELECT photo into :2 from testblob WHERE id = 100; " +
                   " END; ";
    
    // Set command to create Anonymous PL/SQL Block
    OracleCommand cmd = new OracleCommand();
    cmd.CommandText = block;
    cmd.Connection = con;
    
    
    // Since executing an anonymous PL/SQL block, setting the command type
    // as Text instead of StoredProcedure
    cmd.CommandType = CommandType.Text;
    
    // Step 4
    // Setting Oracle parameters
    
    // Bind the parameter as OracleDbType.Blob to command for inserting image
    OracleParameter param = cmd.Parameters.Add("blobtodb", OracleDbType.Blob);
    param.Direction = ParameterDirection.Input;
    
    
    // Assign Byte Array to Oracle Parameter
    param.Value = ImageData;
    
    // Bind the parameter as OracleDbType.Blob to command for retrieving the image
    OracleParameter param2 = cmd.Parameters.Add("blobfromdb", OracleDbType.Blob);
    param2.Direction = ParameterDirection.Output;
    
    // Step 5
    // Execute the Anonymous PL/SQL Block
    
    // The anonymous PL/SQL block inserts the image to the
    // database and then retrieves the images as an output parameter
    cmd.ExecuteNonQuery();
    Console.WriteLine("Image file inserted to database from " + SourceLoc);
    
    // Step 6
    // Save the retrieved image to the DestinationLoc in the file system
    
    // Create a byte array
    byte[] byteData = new byte[0];
    
    // fetch the value of Oracle parameter into the byte array
    byteData = (byte[])((OracleBlob)(cmd.Parameters[1].Value)).Value;
    
    // get the length of the byte array
    int ArraySize = new int();
    ArraySize = byteData.GetUpperBound(0);
    
    // Write the Blob data fetched from database to the filesystem at the
    // destination location
    FileStream fs1 = new FileStream(@DestinationLoc,
                                    FileMode.OpenOrCreate, FileAccess.Write);
    fs1.Write(byteData, 0,ArraySize);
    fs1.Close();
    
    Console.WriteLine("Image saved to " + DestinationLoc + " successfully !");
    Console.WriteLine("");
    Console.WriteLine("***********************************************************");
    Console.WriteLine("Before running this application again, execute 'Listing 1' ");