Mixing
table columns are System.DBNull after inserting them into database
I have a table which looks like this:
CREATE TABLE largeObject(
fileName varchar2(50) primary key,
fileContent blob,
encrypthedFileContent blob
);
And this is my class:
public class Blob
{
public string FileName { get; private set; }
public byte Binary { get; private set; }
public byte EncryptedBinary { get; private set; }
public Blob(string fileName, byte binary, byte encryptedBinary)
{
this.FileName = fileName;
this.Binary = binary;
this.EncryptedBinary = encryptedBinary;
}
public Blob(string FileName)
{
this.FileName = FileName;
}
public override string ToString()
{
return FileName;
}
}
Using this code i add and load the table values from my database:
private static byte encrypth(byte input)
{
PasswordDeriveBytes pdb = new PasswordDeriveBytes("mycoolpassword", new byte { 0x43, 0x87, 0x23, 0x72 });
MemoryStream ms = new MemoryStream();
Aes aes = new AesManaged();
aes.Key = pdb.GetBytes(aes.KeySize / 8);
aes.IV = pdb.GetBytes(aes.BlockSize / 8);
CryptoStream cs = new CryptoStream(ms,
aes.CreateEncryptor(), CryptoStreamMode.Write);
cs.Write(input, 0, input.Length);
cs.Close();
return ms.ToArray();
}
public static Blob ConvertToBlob(string filePath)
{
FileStream fs = new FileStream(filePath, FileMode.Open, FileAccess.Read); //A stream of bytes that represnts the binary file
BinaryReader reader = new BinaryReader(fs); //The reader reads the binary data from the file stream
byte binary = reader.ReadBytes((int)fs.Length); //Bytes from the binary reader stored in BlobValue array
fs.Close();
reader.Close();
return new Blob(filePath, binary,encrypth(binary));
}
public static void SaveToDb(string filePath)
{
Blob blob = ConvertToBlob(filePath);
OleDbCommand cmd = new OleDbCommand("insert into largeObject values(:fileName, :fileContent, :encrypthedFileContent)", conn);
cmd.Parameters.Add(new OleDbParameter(":fileName", Path.GetFileName(blob.FileName)));
cmd.Parameters.Add(new OleDbParameter(":fileContent", blob.Binary));
cmd.Parameters.Add(new OleDbParameter(":encrypthedFileContent", blob.EncryptedBinary));
cmd.ExecuteNonQuery();
}
Now here is the problem. After I add two files in the database the other files which I try to add are System.DBNull and I dont know why. After I add my second-third file I add the next file nothing happens (no error, etc). But after I try to receive the files I get the error that they are System.DBNull.
How do I know that they are System.DBNull?
I tried retreiving every file(largeobject) from the database and I added a if statement whether the byte are null: if ((reader["fileContent"] != System.DBNull.Value) && (reader["encrypthedFileContent"] != System.DBNull.Value))
. It turns out I was right. The only files(largeobjects) I received were the files which I added as first. (because they are not saved as System.DBNull)
What am I doing wrong?
c# sql oracle types dbnull
asked Nov 21 '18 at 17:48
kokos123kokos123
95110
add a comment |
I have a table which looks like this:
CREATE TABLE largeObject(
fileName varchar2(50) primary key,
fileContent blob,
encrypthedFileContent blob
);
And this is my class:
public class Blob
{
public string FileName { get; private set; }
public byte Binary { get; private set; }
public byte EncryptedBinary { get; private set; }
public Blob(string fileName, byte binary, byte encryptedBinary)
{
this.FileName = fileName;
this.Binary = binary;
this.EncryptedBinary = encryptedBinary;
}
public Blob(string FileName)
{
this.FileName = FileName;
}
public override string ToString()
{
return FileName;
}
}
Using this code i add and load the table values from my database:
private static byte encrypth(byte input)
{
PasswordDeriveBytes pdb = new PasswordDeriveBytes("mycoolpassword", new byte { 0x43, 0x87, 0x23, 0x72 });
MemoryStream ms = new MemoryStream();
Aes aes = new AesManaged();
aes.Key = pdb.GetBytes(aes.KeySize / 8);
aes.IV = pdb.GetBytes(aes.BlockSize / 8);
CryptoStream cs = new CryptoStream(ms,
aes.CreateEncryptor(), CryptoStreamMode.Write);
cs.Write(input, 0, input.Length);
cs.Close();
return ms.ToArray();
}
public static Blob ConvertToBlob(string filePath)
{
FileStream fs = new FileStream(filePath, FileMode.Open, FileAccess.Read); //A stream of bytes that represnts the binary file
BinaryReader reader = new BinaryReader(fs); //The reader reads the binary data from the file stream
byte binary = reader.ReadBytes((int)fs.Length); //Bytes from the binary reader stored in BlobValue array
fs.Close();
reader.Close();
return new Blob(filePath, binary,encrypth(binary));
}
public static void SaveToDb(string filePath)
{
Blob blob = ConvertToBlob(filePath);
OleDbCommand cmd = new OleDbCommand("insert into largeObject values(:fileName, :fileContent, :encrypthedFileContent)", conn);
cmd.Parameters.Add(new OleDbParameter(":fileName", Path.GetFileName(blob.FileName)));
cmd.Parameters.Add(new OleDbParameter(":fileContent", blob.Binary));
cmd.Parameters.Add(new OleDbParameter(":encrypthedFileContent", blob.EncryptedBinary));
cmd.ExecuteNonQuery();
}
Now here is the problem. After I add two files in the database the other files which I try to add are System.DBNull and I dont know why. After I add my second-third file I add the next file nothing happens (no error, etc). But after I try to receive the files I get the error that they are System.DBNull.
How do I know that they are System.DBNull?
I tried retreiving every file(largeobject) from the database and I added a if statement whether the byte are null: if ((reader["fileContent"] != System.DBNull.Value) && (reader["encrypthedFileContent"] != System.DBNull.Value))
. It turns out I was right. The only files(largeobjects) I received were the files which I added as first. (because they are not saved as System.DBNull)
What am I doing wrong?
c# sql oracle types dbnull
asked Nov 21 '18 at 17:48
kokos123kokos123
95110
add a comment |
I have a table which looks like this:
CREATE TABLE largeObject(
fileName varchar2(50) primary key,
fileContent blob,
encrypthedFileContent blob
);
And this is my class:
public class Blob
{
public string FileName { get; private set; }
public byte Binary { get; private set; }
public byte EncryptedBinary { get; private set; }
public Blob(string fileName, byte binary, byte encryptedBinary)
{
this.FileName = fileName;
this.Binary = binary;
this.EncryptedBinary = encryptedBinary;
}
public Blob(string FileName)
{
this.FileName = FileName;
}
public override string ToString()
{
return FileName;
}
}
Using this code i add and load the table values from my database:
private static byte encrypth(byte input)
{
PasswordDeriveBytes pdb = new PasswordDeriveBytes("mycoolpassword", new byte { 0x43, 0x87, 0x23, 0x72 });
MemoryStream ms = new MemoryStream();
Aes aes = new AesManaged();
aes.Key = pdb.GetBytes(aes.KeySize / 8);
aes.IV = pdb.GetBytes(aes.BlockSize / 8);
CryptoStream cs = new CryptoStream(ms,
aes.CreateEncryptor(), CryptoStreamMode.Write);
cs.Write(input, 0, input.Length);
cs.Close();
return ms.ToArray();
}
public static Blob ConvertToBlob(string filePath)
{
FileStream fs = new FileStream(filePath, FileMode.Open, FileAccess.Read); //A stream of bytes that represnts the binary file
BinaryReader reader = new BinaryReader(fs); //The reader reads the binary data from the file stream
byte binary = reader.ReadBytes((int)fs.Length); //Bytes from the binary reader stored in BlobValue array
fs.Close();
reader.Close();
return new Blob(filePath, binary,encrypth(binary));
}
public static void SaveToDb(string filePath)
{
Blob blob = ConvertToBlob(filePath);
OleDbCommand cmd = new OleDbCommand("insert into largeObject values(:fileName, :fileContent, :encrypthedFileContent)", conn);
cmd.Parameters.Add(new OleDbParameter(":fileName", Path.GetFileName(blob.FileName)));
cmd.Parameters.Add(new OleDbParameter(":fileContent", blob.Binary));
cmd.Parameters.Add(new OleDbParameter(":encrypthedFileContent", blob.EncryptedBinary));
cmd.ExecuteNonQuery();
}
Now here is the problem. After I add two files in the database the other files which I try to add are System.DBNull and I dont know why. After I add my second-third file I add the next file nothing happens (no error, etc). But after I try to receive the files I get the error that they are System.DBNull.
How do I know that they are System.DBNull?
I tried retreiving every file(largeobject) from the database and I added a if statement whether the byte are null: if ((reader["fileContent"] != System.DBNull.Value) && (reader["encrypthedFileContent"] != System.DBNull.Value))
. It turns out I was right. The only files(largeobjects) I received were the files which I added as first. (because they are not saved as System.DBNull)
What am I doing wrong?
c# sql oracle types dbnull
asked Nov 21 '18 at 17:48
kokos123kokos123
95110
I have a table which looks like this:
CREATE TABLE largeObject(
fileName varchar2(50) primary key,
fileContent blob,
encrypthedFileContent blob
);
And this is my class:
public class Blob
{
public string FileName { get; private set; }
public byte Binary { get; private set; }
public byte EncryptedBinary { get; private set; }
public Blob(string fileName, byte binary, byte encryptedBinary)
{
this.FileName = fileName;
this.Binary = binary;
this.EncryptedBinary = encryptedBinary;
}
public Blob(string FileName)
{
this.FileName = FileName;
}
public override string ToString()
{
return FileName;
}
}
Using this code i add and load the table values from my database:
private static byte encrypth(byte input)
{
PasswordDeriveBytes pdb = new PasswordDeriveBytes("mycoolpassword", new byte { 0x43, 0x87, 0x23, 0x72 });
MemoryStream ms = new MemoryStream();
Aes aes = new AesManaged();
aes.Key = pdb.GetBytes(aes.KeySize / 8);
aes.IV = pdb.GetBytes(aes.BlockSize / 8);
CryptoStream cs = new CryptoStream(ms,
aes.CreateEncryptor(), CryptoStreamMode.Write);
cs.Write(input, 0, input.Length);
cs.Close();
return ms.ToArray();
}
public static Blob ConvertToBlob(string filePath)
{
FileStream fs = new FileStream(filePath, FileMode.Open, FileAccess.Read); //A stream of bytes that represnts the binary file
BinaryReader reader = new BinaryReader(fs); //The reader reads the binary data from the file stream
byte binary = reader.ReadBytes((int)fs.Length); //Bytes from the binary reader stored in BlobValue array
fs.Close();
reader.Close();
return new Blob(filePath, binary,encrypth(binary));
}
public static void SaveToDb(string filePath)
{
Blob blob = ConvertToBlob(filePath);
OleDbCommand cmd = new OleDbCommand("insert into largeObject values(:fileName, :fileContent, :encrypthedFileContent)", conn);
cmd.Parameters.Add(new OleDbParameter(":fileName", Path.GetFileName(blob.FileName)));
cmd.Parameters.Add(new OleDbParameter(":fileContent", blob.Binary));
cmd.Parameters.Add(new OleDbParameter(":encrypthedFileContent", blob.EncryptedBinary));
cmd.ExecuteNonQuery();
}
Now here is the problem. After I add two files in the database the other files which I try to add are System.DBNull and I dont know why. After I add my second-third file I add the next file nothing happens (no error, etc). But after I try to receive the files I get the error that they are System.DBNull.
How do I know that they are System.DBNull?
I tried retreiving every file(largeobject) from the database and I added a if statement whether the byte are null: if ((reader["fileContent"] != System.DBNull.Value) && (reader["encrypthedFileContent"] != System.DBNull.Value))
. It turns out I was right. The only files(largeobjects) I received were the files which I added as first. (because they are not saved as System.DBNull)
What am I doing wrong?
c# sql oracle types dbnull
c# sql oracle types dbnull
asked Nov 21 '18 at 17:48
kokos123kokos123
95110
asked Nov 21 '18 at 17:48
kokos123kokos123
95110
asked Nov 21 '18 at 17:48
kokos123kokos123
95110
asked Nov 21 '18 at 17:48
kokos123kokos123
95110
asked Nov 21 '18 at 17:48
kokos123kokos123
95110
95110
add a comment |
add a comment |
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