Its giving me syntax error please help me I dont know the problem

Question

1.00/5 (1 vote)

See more:

its giving me syntax error please help me i dont know the problem

C#

con.Open();
            OleDbCommand cmd = con.CreateCommand();
            cmd.CommandType = CommandType.Text;
            cmd.CommandText = "update product set LastName=@LastName,FirstName=@FirstName,MiddleName=@MiddleName,Section=@Section where StudentID=@StudentID";
            cmd.Parameters.Clear();
            cmd.Parameters.AddWithValue("@LastName", TextBox1.Text);
            cmd.Parameters.AddWithValue("@FirstName", TextBox2.Text);
            cmd.Parameters.AddWithValue("@MiddleName", TextBox3.Text);
            cmd.Parameters.AddWithValue("@Section", TextBox4.Text);
          //  cmd.Parameters.AddWithValue("@StudentID", TextBox5.Text);
            cmd.ExecuteNonQuery();

What I have tried:

i dont know the problem

C#

con.Open();
            OleDbCommand cmd = con.CreateCommand();
            cmd.CommandType = CommandType.Text;
            cmd.CommandText = "UPDATE product SET LastName='" + TextBox1.Text+ "',FirstName='" + TextBox2.Text + "',MiddleName='" + TextBox3.Text + "',Section='"+TextBox4.Text+"' where StudentID=" + TextBox5.Text + "";
            cmd.ExecuteNonQuery();
            this.Refresh();

            con.Close();

this is my first code

Posted 3-Nov-18 0:01am

Member 14042406

Updated 3-Nov-18 0:13am

OriginalGriff

v2

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

OriginalGriff · Answer 1 · 2018-11-03T00:14:00

The good thing is that you have got rid of the concatenated text version - that is very dangerous!

The next thing to do is find out when you get "a syntax error" - and I'm guessing it's at runtime not compile time, which means it's a problem with the SQL command.
And that means it's likely to be the named parameters, which an OleDbConnection doesn't support in the same way as an SqlConnection.
Because you name a parameter in your query, but comment it out in your cmd.Parameters.AddwithValue list, tejh command processor is probably complainign about the "<pre>where StudentID=@StudentID</pre>" becuase @StudentID will be replaced with a NULL and that's probably the problem

Uncomment the line, and it should work:

cmd.CommandText = "update product set LastName=@LastName,FirstName=@FirstName,MiddleName=@MiddleName,Section=@Section where StudentID=@StudentID";
cmd.Parameters.Clear();
cmd.Parameters.AddWithValue("@LastName", TextBox1.Text);
cmd.Parameters.AddWithValue("@FirstName", TextBox2.Text);
cmd.Parameters.AddWithValue("@MiddleName", TextBox3.Text);
cmd.Parameters.AddWithValue("@Section", TextBox4.Text);
cmd.Parameters.AddWithValue("@StudentID", TextBox5.Text);
cmd.ExecuteNonQuery();

But do remember that the names are irrelevant in OldDb, and can be replaced with placeholders - the order in which they are added controls where they go!

cmd.CommandText = "UPDATE product SET LastName=@LastName, FirstName=?, MiddleName=?, Section=? WHEREStudentID=?";
cmd.Parameters.Clear();
cmd.Parameters.AddWithValue("@LastName", TextBox1.Text);
cmd.Parameters.AddWithValue("@FirstName", TextBox2.Text);
cmd.Parameters.AddWithValue("@MiddleName", TextBox3.Text);
cmd.Parameters.AddWithValue("@Section", TextBox4.Text);
cmd.Parameters.AddWithValue("@StudentID", TextBox5.Text);
cmd.ExecuteNonQuery();