SQL INSERT - Invalid column name
As some of you may of seen from my previous post I'm new to using C# to create websites (Although I have a fair bit of experience using it for Windows Forms apps). The powers that be are tempting me away from PHP but I keep failing at what I consider the basics.
Anyway, this is my issue. I am trying to create a simple entry into a SQL database. I know my connection to the DB is fine as I can reel off 开发者_StackOverflowSELECT queries all day long but I'm having trouble with using Insert.
Heres my code:
string filename = "abc123.jpg";
SqlConnection link = new SqlConnection(//you dont need to see my data here ;));
string sqlcode = "INSERT INTO file_uploads (upload_filename VALUES ("+filename+")";
SqlCommand sql = new SqlCommand(sqlcode,link);
link.open();
sql.ExecuteNonQuery();
This results in "Invalid column name abc123.jpg" returned from the try/catch.
Any help would be appreciated. (I wish they would let me do this in PHP lol!)
Thanks,
Tripbrock
You are missing a parenthesis after the column name and the value represents a string and as such must be enclosed in quotes:
string sqlcode = "INSERT INTO file_uploads (upload_filename) " +
"VALUES ('"+filename+"')";
However, the correct way would be to use a parameterized query:
string filename = "abc123.jpg";
SqlConnection link = new SqlConnection(/*you dont need to see my data here ;)*/);
string sqlcode = "INSERT INTO file_uploads (upload_filename) VALUES (@filename)";
SqlCommand sql = new SqlCommand(sqlcode,link);
sql.Parameters.AddWithValue("@filename", filename);
link.open();
sql.ExecuteNonQuery();
your SQL is bad formatted. Try this :
string sqlcode = "INSERT INTO file_uploads (upload_filename) VALUES ('"+filename+"')";
Where upload_filename is a name of the column
Really you should be parameterising your queries - this reduces the risk of injection attacks:
string filename = "abc123.jpg";
using( SqlConnection link = new SqlConnection(/*...*/;)) )
{
// sql statement with parameter
string sqlcode = "INSERT INTO file_uploads (upload_filename) VALUES (@filename)";
using( SqlCommand sql = new SqlCommand(sqlcode,link) )
{
// add filename parameter
sql.Parameters.AddWithValue("filename", filename);
link.open();
sql.ExecuteNonQuery();
}
}
Also note the using
statements - these make sure that the connection and command objects are disposed of.
Try
string sqlcode = "INSERT INTO file_uploads (upload_filename) VALUES ('"+filename+"')";
You were missing a closing parentheses.
Don't know if it is a typo but the line should be:
string sqlcode = "INSERT INTO file_uploads (upload_filename) VALUES ('"+filename+"')";
Notice the )
after upload_filename
.
Also also added the single quotes around the filename.
But you probably want to use a parameterized query:
string sqlcode = "INSERT INTO file_uploads (upload_filename) VALUES (@filename)";
Then use command.Parameters
to add the actual value.
looks like you are missing a bracket:
string sqlcode = "INSERT INTO file_uploads (upload_filename VALUES ("+filename+")";
Should be
string sqlcode = "INSERT INTO file_uploads (upload_filename) VALUES ('"+filename+"')";
Also, to avoid SQL injection attacks you can use the SQLCommand objects like so.
using (SQLCommand oSQLCommand = new SQLCommand("INSERT INTO file_uploads (upload_filename) VALUES ( @FileName )")
{
oSQLCommand.Parameters.AddWithValue("@FileName", filename);
oSQLCommand.ExecuteNonQuery();
}
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