Ad-hoc retreival of data from SQL Server varbinary column
I would like to retreive some binary data from a varbinary(max)
column in a SQL Server database for debugging purposes.
What is the easiest way to get this data into a local binary file, preferably without having to write a throw-away console application?
I have tried using SQL Server Management Studio (with the "results to file" option) but this outputs a hex encoded binary string to the file, rather than the raw bi开发者_Python百科nary data.
I can't think of any easier way to do this than a throw away bit of C#...
static void Main(string[] args)
{
GetBinaryDataToFile("Server=localhost;Initial Catalog=ReportServer;Integrated Security=true", "D:\\temp.dat");
}
public static void GetBinaryDataToFile(string connectionString, string path)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
connection.Open();
using (SqlCommand command = connection.CreateCommand())
{
command.CommandText = "SELECT Sid FROM Users WHERE UserID = '62066184-8403-494E-A571-438ABF938A4F'";
command.CommandType = CommandType.Text;
using (SqlDataReader dataReader = command.ExecuteReader())
{
if (dataReader.Read())
{
SqlBinary sqlBinary = dataReader.GetSqlBinary(0);
File.WriteAllBytes(path, sqlBinary.Value);
}
dataReader.Close();
}
}
connection.Close();
}
}
This code has been tested using the Users.Sid column (which is of varbinary type) in a default installation of SQL Server wih Reporting Services.
I loved the LinqPad suggestion. I tried it and had a query that spit out the binary to a file within 10 minutes. No VS Project, no build - and now the script is saved and I can pull it up anytime. So cool!
LinqPad script:
var g = from pd in Archives
where pd.ArchiveId == 123
select pd;
var q = from p in printDocs
where p.DocumentId == g.SingleOrDefault().DocumentId
select p;
File.WriteAllBytes("C:\\temp.pdf", q.SingleOrDefault().Pdf.ToArray());
I've found this solution with bcp
command (run from command prompt):
c:\temp>bcp "select MYVARBINARYCOL from MYTABLE where id = 1234" queryout "c:\filename.pdf" -S MYSQLSERVER\MYINSTANCE -T
Enter the file storage type of field filedata [varbinary(max)]:
Enter prefix-length of field filedata [8]: 0
Enter length of field filedata [0]:
Enter field terminator [none]:
Do you want to save this format information in a file? [Y/n] n
Starting copy...
1 rows copied.
Network packet size (bytes): 4096
Clock Time (ms.) Total : 15 Average : (66.67 rows per sec.)
I used the -T option to use windows authentication to connect to the DB. If you use password auth, you'll need to use the -U and -P switches to specify a username and password.
But I also like LinqPad suggestion in Robb Sadler's answer and somehow prefer it.
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