Trouble with updating database data - sql

Question

I'm having trouble with my UPDATE statement in which I'm trying to update table data through WHERE clause, which gives me error of data miss-match.
sqL = "UPDATE Customer SET name= '" & txtName.Text & "', adress= '" & txtAdress.Text & "', contact = '" & txtContact.Text & "' WHERE Customer_ID = '" & txtCustomerID.Text & "'"
I've also tried
sqL = "UPDATE Customer SET name= '" & txtName.Text & "', adress= '" & txtAdress.Text & "', contact = '" & txtContact.Text & "' WHERE Customer_ID = '" & Convert.ToInt32(txtCustomerID.Text) & "'"
with no luck.

Answer 1

Please use a parameterised query which is much cleaner and safer:
If you are on c#:
string sql = "UPDATE Customer SET name= #name, adress=#address, contact = #contact" +
" WHERE Customer_ID = #id";
using(SqlConnection conn = new SqlConnection("yourConnectionString"))
{
SqlCommand cmd = new SqlCommand(sql, conn);
cmd.Parameters.AddWithValue("#name",txtName.Text);
cmd.Parameters.AddWithValue("#address",txtAdress.Text);
cmd.Parameters.AddWithValue("#contact",txtContact.Text);
/*
NOTE: Make sure Textbox value is convertible to Customer_ID data type
before executing the query. It should be done before the using statement.
Use string.Trim() method to remove any space characters at start/end
*/
cmd.Parameters.AddWithValue("#id",txtCustomerID.Text.Trim());
conn.Open();
cmd.ExecuteNonQuery();
}

Answer 2

It looks like the data type of Customer_ID is an int. In that case, remove the single quotes from around your convert statement.
sqL = "UPDATE Customer SET name= '" & txtName.Text & "', adress= '" & txtAdress.Text & "', contact = '" & txtContact.Text & "' WHERE Customer_ID = " & Convert.ToInt32(txtCustomerID.Text)
But do double check the data type in your table to be sure.

Answer 3

Your query will not compile :-
The string concatenation operator in C# is plus sign not ampersand.
however as kaf advised always use parametrized queries.
Try using plus sign instead of an ampersand.
"UPDATE Customer SET name= '" + txtName.Text + "', adress= '" + txtAdress.Text + "', contact = '" + txtContact.Text + "' WHERE Customer_ID = '" + txtCustomerID.Text + "'"
If customer ID is int ,convert it to int .