Incorrect syntax inserting data into table - c#

I am having some trouble with my update() method. The idea is that the user Provides a recipe name, ingredients, instructions and then selects an image using Filestream.
Once the user clicks 'Add Recipe' this will call the update method, however as things stand I am getting an error which is mentioning the contents of the text box:
Here is the update() method code:
private void updatedata()
{
// filesteam object to read the image
// full length of image to a byte array
try
{
// try to see if the image has a valid path
if (imagename != "")
{
FileStream fs;
fs = new FileStream(#imagename, FileMode.Open, FileAccess.Read);
// a byte array to read the image
byte[] picbyte = new byte[fs.Length];
fs.Read(picbyte, 0, System.Convert.ToInt32(fs.Length));
fs.Close();
//open the database using odp.net and insert the lines
string connstr = #"Server=mypcname\SQLEXPRESS;Database=RecipeOrganiser;Trusted_Connection=True";
SqlConnection conn = new SqlConnection(connstr);
conn.Open();
string query;
query = "insert into Recipes(RecipeName,RecipeImage,RecipeIngredients,RecipeInstructions) values (" + textBox1.Text + "," + " #pic" + "," + textBox2.Text + "," + textBox3.Text + ")";
SqlParameter picparameter = new SqlParameter();
picparameter.SqlDbType = SqlDbType.Image;
picparameter.ParameterName = "pic";
picparameter.Value = picbyte;
SqlCommand cmd = new SqlCommand(query, conn);
cmd.Parameters.Add(picparameter);
cmd.ExecuteNonQuery();
MessageBox.Show("Image successfully saved");
cmd.Dispose();
conn.Close();
conn.Dispose();
Connection();
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
Can anyone see where I have gone wrong with the insert into Recipes query or suggest an alternative approach to this part of the code?

Your code is open to SQL Injection, but probably your error comes from some text that contains a single quote (the instructions fields for example) and this break your command string build using concatenating the user input.
EDIT
As someone pointed in comment the error is caused by the missing quotes around your textboxes. But while easy to fix that's not the way to go because it is wrong to fix the error adding the missing quotes. It is just postponig the problem leaving a big security hole waiting to be exploited.
A parameterized query could avoid all this mess.
string connstr = "....";
string query = "insert into Recipes(RecipeName,RecipeImage,RecipeIngredients,RecipeInstructions) " +
"values (#name, #pic, #ing, #instr)";
using(SqlConnection conn = new SqlConnection(connstr))
using(SqlCommand cmd = new SqlCommand(query, conn))
{
conn.Open();
SqlParameter picparameter = new SqlParameter();
picparameter.SqlDbType = SqlDbType.Image;
picparameter.ParameterName = "#pic";
picparameter.Value = picbyte;
cmd.Parameters.Add(picparameter);
cmd.Parameters.AddWithValue("#name", textbox1.Text);
cmd.Parameters.AddWithValue("#ing", textbox2.Text);
cmd.Parameters.AddWithValue("#instr", textbox3.Text);
cmd.ExecuteNonQuery();
MessageBox.Show("Image successfully saved");
}

Since you using string concatenations, you probably missed a quote or you put an extra quote or missed a comma or put extra comma etc etc....
Don't use this way!
Your error doesn't look obviously but you should always use parameterized queries. This kind of string concatenations are open for SQL Injection attacks.
query = "insert into Recipes(RecipeName,RecipeImage,RecipeIngredients,RecipeInstructions) values (#p1, #pic, #p3, #p4)";
SqlCommand cmd = new SqlCommand(query, conn);
cmd.Parameters.AddWithValue(#p1, textBox1.Text);
cmd.Parameters.AddWithValue(#pic, textBox1.Text);
cmd.Parameters.AddWithValue(#p3, textBox1.Text);
cmd.Parameters.AddWithValue(#p4, picparameter);

try this
query = "insert into Recipes(RecipeName,RecipeImage,RecipeIngredients,RecipeInstructions) values ('" + textBox1.Text + "'," + " #pic" + ",'" + textBox2.Text + "','" + textBox3.Text + "')";

Related

Invalid object name 'Main' error when inserting into Database - C# (WebForms), MySql

I know plenty of people have these issues, and I've actually tried to implement some of the suggestions to my code, however I'm getting errors that just don't make sense to me. This is my first time implementing database calls to my code. Can someone please tell me what I'm doing wrong? The following error pops up: ERROR: Invalid object name 'Main'. This is actually triggered by my exception so at least something is working. Otherwise, I don't know what the issue is. On the DB end, I have (username VARCHAR, email VARCHAR and number NCHAR) Please see the code below
static string path = Path.GetFullPath(Environment.CurrentDirectory);
static string databaseName = "u_DB.mdf";
string connectionString = #"Data Source=(localdb)\MSSQLLocalDB;AttachDbFilename=" + path + #"\" + databaseName + "; Integrated Security=True;";
private void button1_Click(object sender, EventArgs e)
{
// string query = "INSERT INTO UserInfo '" + textBox1.Text + "' and password = '" + textBox2.Text + "'";
string query = "insert into Main ([username], [email], [number]) values(#username,#email,#number)";
using (SqlConnection con = new SqlConnection(connectionString))
{
try
{
con.Open();
using (SqlCommand cmd = new SqlCommand(query, con))
{
cmd.Parameters.Add("#username", SqlDbType.VarChar).Value = textBox3.Text;
cmd.Parameters.Add("#email", SqlDbType.VarChar).Value = textBox2.Text;
cmd.Parameters.AddWithValue("#number", SqlDbType.VarChar).Value = textBox1.Text;
int rowsAdded = cmd.ExecuteNonQuery();
if (rowsAdded > 0)
MessageBox.Show("Added to Database");
else
MessageBox.Show("Nothing was added");
}
}
catch (Exception ex)
{
MessageBox.Show("ERROR: " + ex.Message);
}
con.Close();
}
}
Firstly, as Chetan assumed, do you have a main table?
The syntax of the query you are using is :
INSERT INTO table_name (column1, column2, column3, ...)
VALUES (value1, value2, value3, ...);
Furthermore,
AddWithValue(string parameterName, object value (<== The actual value to insert!));
in your case
AddWithValue("#number", textBox1.Text);
is enough.

Invalid attempt to call read when reader is closed when inserting data

i have a button that when clicked inserts data from textbox and combobox fields into database tables, but every time i insert it gives me "Invalid attempt to call read when reader is closed". How can i get rid of this error. And tips on optimising the code are welcome, because i know im a total noob. thanks
private void btnSave_Click(object sender, RoutedEventArgs e)
{
try
{
SqlConnection sqlCon = new SqlConnection(#"Data Source=(localdb)\mssqllocaldb; Initial Catalog=Storagedb;");
sqlCon.Open();
string Query1 = "insert into location(Storage, Shelf, columns, rows) values(" + txtWarehouse.Text + ", " + txtShelf.Text + ", " + txtColumn.Text + ", " + txtRow.Text + ")";
SqlCommand sqlCmd = new SqlCommand(Query1, sqlCon);
SqlDataAdapter dataAdp = new SqlDataAdapter(sqlCmd);
dataAdp.SelectCommand.ExecuteNonQuery();
sqlCon.Close();
}
catch (Exception er)
{
MessageBox.Show(er.Message);
}
try
{
SqlConnection sqlCon = new SqlConnection(#"Data Source=(localdb)\mssqllocaldb; Initial Catalog=Storagedb;");
sqlCon.Open();
string Query3 = "SELECT LOCATION_ID FROM LOCATION WHERE storage='" + txtWarehouse.Text + "' AND shelf='" + txtShelf.Text + "' AND columns='"
+ txtColumn.Text + "' AND rows='" + txtRow.Text + "'";
SqlCommand sqlCmd1 = new SqlCommand(Query3, sqlCon);
SqlDataReader dr = sqlCmd1.ExecuteReader(); ;
while (dr.Read())
{
string LocationId = dr[0].ToString();
dr.Close();
string Query2 = "insert into product(SKU, nimetus, minimum, maximum, quantity,location_ID,category_ID,OrderMail_ID) values ('" + txtSku.Text + "','" + txtNimetus.Text + "', '"
+ txtMin.Text + "', '" + txtMax.Text + "', '" + txtQuan.Text + "', '" + LocationId + "', '" + (cbCat.SelectedIndex+1) + "', '" + (cbMail.SelectedIndex+1) + "')";
SqlCommand sqlCmd = new SqlCommand(Query2, sqlCon);
SqlDataAdapter dataAdp = new SqlDataAdapter(sqlCmd);
dataAdp.SelectCommand.ExecuteNonQuery();
}
sqlCon.Close();
}
catch (Exception ed)
{
MessageBox.Show(ed.Message);
}
}
Let's try to make some adjustments to your code.
First thing to consider is to use a parameterized query and not a
string concatenation when you build an sql command. This is mandatory
to avoid parsing errors and Sql Injections
Second, you should encapsulate the disposable objects in a using statement
to be sure they receive the proper disposal when you have finished to
use them.
Third, you can get the LOCATION_ID from your table without running a
separate query simply adding SELECT SCOPE_IDENTITY() as second batch to your first command. (This works only if you have declared the LOCATION_ID field in the first table as an IDENTITY column)
Fourth, you put everything in a transaction to avoid problems in case
some of the code fails unexpectedly
So:
SqlTransaction tr = null;
try
{
string cmdText = #"insert into location(Storage, Shelf, columns, rows)
values(#storage,#shelf,#columns,#rows);
select scope_identity()";
using(SqlConnection sqlCon = new SqlConnection(.....))
using(SqlCommand cmd = new SqlCommand(cmdText, sqlCon))
{
sqlCon.Open();
using( tr = sqlCon.BeginTransaction())
{
// Prepare all the parameters required by the command
cmd.Parameters.Add("#storage", SqlDbType.Int).Value = Convert.ToInt32(txtWarehouse.Text);
cmd.Parameters.Add("#shelf", SqlDbType.Int).Value = Convert.ToInt32(txtShelf.Text);
cmd.Parameters.Add("#columns", SqlDbType.Int).Value = Convert.ToInt32(txtColumn.Text );
cmd.Parameters.Add("#rows", SqlDbType.Int).Value = Convert.ToInt32(txtRow.Text);
// Execute the command and get back the result of SCOPE_IDENTITY
int newLocation = Convert.ToInt32(cmd.ExecuteScalar());
// Set the second command text
cmdText = #"insert into product(SKU, nimetus, minimum, maximum, quantity,location_ID,category_ID,OrderMail_ID)
values (#sku, #nimetus,#min,#max,#qty,#locid,#catid,#ordid)";
// Build a new command with the second text
using(SqlCommand cmd1 = new SqlCommand(cmdText, sqlCon))
{
// Inform the new command we are inside a transaction
cmd1.Transaction = tr;
// Add all the required parameters for the second command
cmd1.Parameters.Add("#sku", SqlDbType.NVarChar).Value = txtSku.Text;
cmd1.Parameters.Add("#nimetus",SqlDbType.NVarChar).Value = txtNimetus.Text;
cmd1.Parameters.Add("#locid", SqlDbType.Int).Value = newLocation;
.... and so on for the other parameters required
cmd1.ExecuteNonQuery();
// If we reach this point the everything is allright and
// we can commit the two inserts together
tr.Commit();
}
}
}
}
catch (Exception er)
{
// In case of exceptions do not insert anything...
if(tr != null)
tr.Rollback();
MessageBox.Show(er.Message);
}
Notice that in the first command I use parameters of type SqlDbType.Int because you haven't used single quotes around your text. This should be verified against the real data type of your table columns and adjusted to match the type. This is true as well for the second command where you put everything as text albeit some of those fields seems to be integer (_location_id_ is probably an integer). Please verify against your table.

Unable to insert a row with parameter

I am trying following code:
try
{
SqlConnection conn = new SqlConnection("server=ARSLAN-LAPI\\SQLEXPRESS;" +
"Trusted_Connection=yes;" +
"database=OTTS; " +
"connection timeout=30");
conn.Open();
String name=UserName.Text;
String pwd=Password.Text;
String query = "INSERT INTO dbo.user (username,password)
VALUES(#username,#password)";
SqlCommand command = new SqlCommand(query, conn);
command.Parameters.Add("#username",name);
command.Parameters.Add("#password",pwd);
command.ExecuteNonQuery();
conn.Close();
ErrorMessage.Text="Well done!";
}
catch(SqlException ex)
{
ErrorMessage.Text="You failed!" + ex.Message;
}
Received error that
You failed!Incorrect syntax near the keyword 'user'.
Please guide me..
User is a reserved keyword, I strongly suggest to change that field name to something different.
However, if you still insist in using it, remember to enclose it in square brackets every time you need it.
string query = "INSERT INTO [dbo].[user] (username,password) VALUES(#username,#password)";
Try this:
INSERT INTO dbo.[user] (username,password) VALUES(#username,#password)
try something like this,
SqlCommand command = new SqlCommand(query, conn);
command.Parameters.Add("#username",SqlDbType.VarChar,50).Value = name;
command.Parameters.Add("#password",SqlDbType.VarChar,50).Value= pwd;
command.ExecuteNonQuery();

multiple queries on 1 button click

I want to perform 2 queries in one button click. I tried the
string query = "first query";
query+="second query";
But this didn't work it shows error.
I have now created 2 separate connections like below:
try
{
SqlConnection conn1 = new SqlConnection(ConfigurationManager.ConnectionStrings["ConnectionStringDatabase"].ConnectionString);
//open connection with database
conn1.Open();
//query to select all users with teh given username
SqlCommand com1 = new SqlCommand("insert into artikulli (tema,abstrakti, kategoria_id, keywords ) values (#tema, #abstrakti, #kategoria, #keywords)", conn1);
// comand.Parameters.AddWithValue("#id", iD);
com1.Parameters.AddWithValue("#tema", InputTitle.Value);
com1.Parameters.AddWithValue("#abstrakti", TextareaAbstract.Value);
com1.Parameters.AddWithValue("#kategoria", DropdownCategory.Value);
com1.Parameters.AddWithValue("#keywords", InputTags.Value);
//execute queries
com1.ExecuteNonQuery();
conn1.Close();
if (FileUploadArtikull.HasFile)
{
int filesize = FileUploadArtikull.PostedFile.ContentLength;
if (filesize > 4194304)
{
ScriptManager.RegisterStartupScript(this, this.GetType(), "popup", "alert('Maximumi i madhesise eshte 4MB');", true);
}
else
{
string filename = "artikuj/" + Path.GetFileName(FileUploadArtikull.PostedFile.FileName);
SqlConnection conn2 = new SqlConnection(ConfigurationManager.ConnectionStrings["ConnectionStringDatabase"].ConnectionString);
SqlCommand com2 = new SqlCommand("insert into artikulli(path) values ('" + filename + "')", conn2);
//open connection with database
conn2.Open();
com2.ExecuteNonQuery();
FileUploadArtikull.SaveAs(Server.MapPath("~/artikuj\\" + FileUploadArtikull.FileName));
Response.Redirect("dashboard.aspx");
}
}
else
{
ScriptManager.RegisterStartupScript(this, this.GetType(), "popup", "alert('Ju nuk keni perzgjedhur asnje file');", true);
}
}
But the problem is that only the second query is performed and the firs is saved as null in database
In your case, there is no reason to open two connections. In addition, the C# language has evolved, so I recommend using the power given by the new language constructs (using, var).
Here is an improved version that should work assuming that the values you bind to your parameters are valid:
try
{
using(var connection = new SqlConnection(ConfigurationManager.ConnectionStrings["ConnectionStringDatabase"].ConnectionString))
{
//open connection with database
connection.Open();
//query to select all users with teh given username
using(var command1 = new SqlCommand("insert into artikulli (tema,abstrakti, kategoria_id, keywords ) values (#tema, #abstrakti, #kategoria, #keywords)", connection))
{
command1.Parameters.AddWithValue("#tema", InputTitle.Value);
command1.Parameters.AddWithValue("#abstrakti", TextareaAbstract.Value);
command1.Parameters.AddWithValue("#kategoria", DropdownCategory.Value);
command1.Parameters.AddWithValue("#keywords", InputTags.Value);
//execute first query
command1.ExecuteNonQuery();
}
//build second query
string filename = "artikuj/" + Path.GetFileName(FileUploadArtikull.PostedFile.FileName);
using(SqlCommand command2 = new SqlCommand("insert into artikulli(path) values (#filename)", connection))
{
//add parameters
command2.Parameters.AddWithValue("#filename", filename);
//execute second query
command2.ExecuteNonQuery();
}
}
}
//TODO: add some exception handling
//simply wrapping code in a try block has no effect without a catch/finally
Try below code, No need to open the connection twice
string query1 = "insert into artikulli (tema,abstrakti, kategoria_id, keywords ) values (#tema, #abstrakti, #kategoria, #keywords)";
SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["ConnectionStringDatabase"].ConnectionString);
SqlCommand com1= new SqlCommand(query1, conn);
com1.Parameters.AddWithValue("#tema", InputTitle.Value);
com1.Parameters.AddWithValue("#abstrakti", TextareaAbstract.Value);
com1.Parameters.AddWithValue("#kategoria", DropdownCategory.Value);
com1.Parameters.AddWithValue("#keywords", InputTags.Value);
string query2 = "insert into artikulli(path) values ('" + filename + "')", conn);
comm.ExecuteNonQuery();
comm.CommandText = query2;
comm.ExecuteScalar();

Adding rows to a SQL Server database from data entered by user in asp.net c#

string ConnectionString = WebConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
SqlConnection connection = new SqlConnection(ConnectionString);
SqlCommand cmd = new SqlCommand("INSERT INTO Data (Name, Sur-Name, Score,Avg) VALUES ('" + fName + "','" + sName + "','" + lblScore.Text + "','" + lblAvg.Text + "');");
cmd.CommandType = CommandType.Text;
cmd.Connection = connection;
cmd.Parameters.AddWithValue("#Name", fName);
cmd.Parameters.AddWithValue("#Sur-Name", sName);
cmd.Parameters.AddWithValue("#Score", lblScore.Text);
cmd.Parameters.AddWithValue("#Avg", lblAvg.Text);
try
{
connection.Open();
cmd.ExecuteNonQuery();
}
catch (Exception exc)
{
lblData.Text = exc.Message;
}
finally
{
connection.Close();
}
The error I keep getting is a runtime saying
Incorrect syntax near '-'. Incorrect syntax near '-'.
I used the try catch just so page would load and my scores show but the label says this Incorrect syntax as well, I was wondering could anyone please help me with what I am doing wrong
Thanks.
I think Sur-Name breaks your query. Use it with square brackets like [Sur-Name]
But more important, please use parameterized queries. This kind of string concatenations are open for SQL Injection attacks. I see you tried to use but you never declare your parameter names in your query.
Also DATA might be a reserved keyword on future versions of SQL Server. You might need to use with also like [DATA]
Consider to use using statement to dispose your SqlConnection and SqlCommand.
using(SqlConnection connection = new SqlConnection(ConnectionString))
using(SqlCommand cmd = connection.CreateCommand())
{
cmd.CommandText = #"INSERT INTO [Data] (Name, [Sur-Name], Score, Avg)
VALUES (#Name, #SurName, #Score, #Avg)";
cmd.Connection = connection;
cmd.Parameters.AddWithValue("#Name", fName);
cmd.Parameters.AddWithValue("#SurName", sName);
cmd.Parameters.AddWithValue("#Score", lblScore.Text);
cmd.Parameters.AddWithValue("#Avg", lblAvg.Text);
try
{
connection.Open();
cmd.ExecuteNonQuery();
}
catch (Exception exc)
{
lblData.Text = exc.Message;
}
}
You are trying to mix concatenated queries with parametrized. Always use parametrized queries, It will save you from SQL Injection.
SqlCommand cmd = new SqlCommand(#"INSERT INTO [Data] (Name, [Sur-Name], Score,Avg) VALUES (
#Name, #SurName, #Score, #Avg)");
cmd.CommandType = CommandType.Text;
cmd.Connection = connection;
cmd.Parameters.AddWithValue("#Name", fName);
cmd.Parameters.AddWithValue("#SurName", sName);
cmd.Parameters.AddWithValue("#Score", lblScore.Text);
cmd.Parameters.AddWithValue("#Avg", lblAvg.Text);
Also consider enclosing your connection and command object in using statement.
As #Soner has mentioned in his answer, use Square brackets for Data and Sur-Name

Categories