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C# Asp.net Webforms simple SQL Query for 1 row several columns to variables

I have been searching around and I am either confusing myself or not searching for the right thing.
I have this data reader that pulls some information for a store procedure.. but I don't think I am doing it right.
string constr = ConfigurationManager.ConnectionStrings["PAYROLL"].ConnectionString;
using (SqlConnection con = new SqlConnection(constr))
{
using (SqlCommand cmd = new SqlCommand("DLI_EMPLOYEE_PORTAL_EMPLOYEE_INFORMATION"))
{
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("#EID", Session["sessionEMPID"].ToString());
cmd.Connection = con;
con.Open();
SqlDataReader dataReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
while (dataReader.Read())
{
string EMP_FIRST = dataReader["FIRST_NAME"].ToString();
string EMP_LAST = dataReader["LAST_NAME"].ToString();
string EMP_DEPT = dataReader["DEPT"].ToString();
string EMP_DEPT_ID = dataReader["DEPT_ID"].ToString();
body = body + "<p>SUBMITTED BY : (" + Session["sessionEMPID"].ToString() + ") " + EMP_FIRST + " " + EMP_LAST + " - DEPT : " + EMP_DEPT + "</p> " + System.Environment.NewLine;
}
con.Close();
}
}
I just need to query one row based of an employee ID.. and I would rather do it not by stored procedure but a select query.
SELECT e.FIRST_NAME, e.LAST_NAME, e.DEPT_ID, d.NAME
FROM EMPLOYEE AS e
INNER JOIN DEPARTMENT AS d ON e.DEPT_ID = d.ID
WHERE (e.ID = 'sim01')
I am building an HTML body string so that is why I need the information.
body = body + "<p>SUBMITTED BY : (" + Session["sessionEMPID"].ToString() + ") " + EMP_FIRST + " " + EMP_LAST + " - DEPT : " + EMP_DEPT + "</p> " + System.Environment.NewLine;
Any help is greatly appreciated. Thank you.

If all you want to do is use a query instead of a stored procedure, just pass your SQL statement to the Command and set your CommandType to Text. If you only ever expect one row, use if (dataReader.Read() instead of while (dataReader.Read()).
string constr = ConfigurationManager.ConnectionStrings["PAYROLL"].ConnectionString;
using (SqlConnection con = new SqlConnection(constr))
{
using (SqlCommand cmd = new SqlCommand(
"SELECT e.FIRST_NAME, e.LAST_NAME, e.DEPT_ID, d.NAME " +
"FROM EMPLOYEE AS e " +
"INNER JOIN DEPARTMENT AS d ON e.DEPT_ID = d.ID " +
"WHERE (e.ID = #EID)"));
{
cmd.CommandType = CommandType.Text;
cmd.Parameters.AddWithValue("#EID", Session["sessionEMPID"].ToString());
cmd.Connection = con;
con.Open();
SqlDataReader dataReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
if (dataReader.Read())
{
string EMP_FIRST = dataReader["FIRST_NAME"].ToString();
string EMP_LAST = dataReader["LAST_NAME"].ToString();
string EMP_DEPT = dataReader["DEPT"].ToString();
string EMP_DEPT_ID = dataReader["DEPT_ID"].ToString();
body = body + "<p>SUBMITTED BY : (" + Session["sessionEMPID"].ToString() + ") " + EMP_FIRST + " " + EMP_LAST + " - DEPT : " + EMP_DEPT + "</p> " + System.Environment.NewLine;
}
con.Close();
}
}
If the query can return more than one row, you can add TOP 1 to the query with an ORDER BY <some other field> to grab only the most relevant one.

It us better to use query instead of stored procedure if there is no TSQL logic

Why is my SQL code in C# not working?

I wrote a SQL command to save some items in my database. But when I run it, it gives an error message:
And here is my code:
public void Opslaan(string titel, string rVoornaam, string rAchternaam, decimal beoordeling, string a1Voornaam, string a1Achternaam, string a2Voornaam, string a2Achternaam, string a3Voornaam, string a3Achternaam)
{
if (beoordelingBest < beoordeling)
{
titelBest = titel;
beoordelingBest = beoordeling;
}
string queryString = "INSERT INTO Films (titel, beoordeling) VALUES('" + titel + "', " + beoordeling + ");" +
"INSERT INTO Acteurs (voornaam, achternaam, FilmID) VALUES('" + a1Voornaam + "' , '" + a1Achternaam + "', (SELECT FilmID from Films where titel = '" + titel + "'));" +
"INSERT INTO Acteurs (voornaam, achternaam, FilmID) VALUES('" + a2Voornaam + "' , '" + a2Achternaam + "', (SELECT FilmID from Films where titel = '" + titel + "'));" +
"INSERT INTO Acteurs (voornaam, achternaam, FilmID) VALUES('" + a3Voornaam + "' , '" + a3Achternaam + "', (SELECT FilmID from Films where titel = '" + titel + "'));" +
"INSERT INTO Regisseurs (voornaam, achternaam, FilmID) VALUES('" + rVoornaam + "' , '" + rAchternaam + "', (SELECT FilmID from Films where titel = '" + titel + "'));";
command = new SqlCommand(queryString, con);
Can someone please help me with this? I can't figure it out.

Use parametererized queries and do not use string concatination. This is to prevent sql injection attacks but also errors with the values like forgetting to make sure strins are escaped (if a string contains a ' for example).
If you have multiple queries each unique parameter value should have its own parameter name/value
Wrap your ado.net database types (SqlConnection, SqlCommand, etc) in using blocks if they are disposable
Never reuse connections as global objects, create, use, and destroy them when needed.
Here is the updated code with 1 statement, you can append additional statements to this and add more parameters as necessary.
var query = "INSERT INTO Acteurs (voornaam, achternaam, FilmID) SELECT #a1Voornaam, #a1Achternaam, FilmID from Films WHERE titel = #title";
using(var con = new SqlConnection("connection string here"))
using(var command = new SqlCommand(queryString, con))
{
command.Parameters.Add(new SqlParameter("#a1Voornaam", SqlDbType.VarChar){Value = a1Voornaam});
command.Parameters.Add(new SqlParameter("#achternaam", SqlDbType.VarChar){Value = achternaam});
command.Parameters.Add(new SqlParameter("#title", SqlDbType.VarChar){Value = title});
con.Open();
command.ExecuteNonQuery();
}

Perhaps one of your values is ');
That would terminate the INSERT statement early, and cause the error.
|
V
INSERT INTO Films (titel, beoordeling) VALUES('');,'anything');
You should use SqlParameters instead of string concatenation.

Are you using TextBoxes? I can't tell for sure. Try something like this, and change to suit your specific needs.
using System.Data.SqlClient;
protected void Button1_Click(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection(System.Configuration.
ConfigurationManager.ConnectionStrings["con"].ToString());
try
{
string query = "insert into UserDetail(Name,Address)
values('" + txtName.Text + "','" + txtAddress.Text + "');";
SqlDataAdapter da = new SqlDataAdapter(query, con);
con.Open();
da.SelectCommand.ExecuteNonQuery();
con.Close();
lblmessage.Text = "Data saved successfully.";
}
catch
{
con.Close();
lblmessage.Text = "Error while saving data.";
}
}

using windows form c# to add values to Mysql database

I need to get the userid(primary key auto_increment) from another table(login) into userdetails table. When trying to run it I keep getting this error " incorrect integer value: 'LAST_INSERT_ID()' for column 'userid' at row 1".
I've tried to take LAST_INSERT_ID() out and run another query after query4 to insert the value into the userid but I can't get it to insert into the right row it just opens a new row.
this is the code am trying to run.
try
{
//This is my connection string i have assigned the database file address path
string MyConnection2 = "datasource=localhost;port=3310;database=e-votingsystem;username=root;password=Password12;";
//this is my insert query in which i am taking input from the user through windows forms
string Query2 = "INSERT INTO vote (username) VALUE ('" + usernameInputBox.Text + "');";
string Query3 = "INSERT INTO login (username,upassword) VALUE ('" + usernameInputBox.Text + "','" + passwordInputBox.Text + "');";
string Query4 = "INSERT INTO userdetails (nationalinsurance,userid,forename,middlename,surname,housenumber,street,towncity,postcode,suffix) VALUES ('" + nationalInsuranceInputBox.Text + "','"+"LAST_INSERT_ID()"+"','" + forenameInputBox.Text + "','" + middleNameInputBox.Text + "','" + surnameInputBox.Text + "','" + houseNumberInputBox.Text + "','" + streetTextBox.Text + "','" + towncityTextBox.Text + "','" + postcodeInputBox.Text + "','" + suffixComboBox.Text+"');";
//This is MySqlConnection here i have created the object and pass my connection string.
MySqlConnection MyConn2 = new MySqlConnection(MyConnection2);
//This is command class which will handle the query and connection object.
MySqlCommand MyCommand2 = new MySqlCommand(Query2, MyConn2);
MySqlCommand MyCommand3 = new MySqlCommand(Query3, MyConn2);
MySqlCommand MyCommand4 = new MySqlCommand(Query4, MyConn2);
MySqlDataReader MyReader2;
MySqlDataReader MyReader3;
MySqlDataReader MyReader4;
// opens new connection to database then executes command
MyConn2.Open();
MyReader2 = MyCommand2.ExecuteReader(); // Here the query will be executed and data saved into the database.
while (MyReader2.Read())
{
}
MyConn2.Close();
// opens new connection to database then executes command
MyConn2.Open();
MyReader3 = MyCommand3.ExecuteReader();
while (MyReader3.Read())
{
}
MyConn2.Close();
//opens new connection to database the exexcutes command
MyConn2.Open();
MyReader4 = MyCommand4.ExecuteReader();
while (MyReader4.Read())
{
}
MyConn2.Close();
}
catch(Exception ex)
{
MessageBox.Show(ex.Message);
}
MessageBox.Show("Hello " + forename + surname, "read and accept the terms and conditions to continue");
//new termsAndConditionsPage().Show();
//Hide();
}

As explained in other answer, you have the LAST_INSERT_ID between single quotes and this transform it in a literal string not in a statement to execute. However also removing the quotes I am not sure that you can retrieve the LAST_INSERT_ID using a connection different from the one that originates the AUTOINCREMENT number on the login table. In any case you should use a different approach and, as a first thing, you should remove ASAP the string concatenations and use parameters (Reason: Sql Injection or SurName = O'Neill)
string Query2 = "INSERT INTO vote (username) VALUE (#uname)";
string Query3 = #"INSERT INTO login (username,upassword) VALUE (#uname, #upass);
SELECT LAST_INSERT_ID();";
string Query4 = #"INSERT INTO userdetails
(nationalinsurance,userid,forename,middlename,
surname,housenumber,street,towncity,postcode,suffix)
VALUES (#insurance, #userid, #forename, #middlename,
#surname, #housenum, #street, #town, #postcode, #suffix)";
Now open just one connection and build three commands, all between an using statement
using(MySqlConnection con = new MySqlConnection(.....constring here....))
using(MySqlCommand cmd2 = new MySqlCommand(Query2, con))
using(MySqlCommand cmd3 = new MySqlCommand(Query3, con))
using(MySqlCommand cmd4 = new MySqlCommand(Query4, con))
{
con.Open();
// Add the parameter to the first command
cmd2.Parameters.Add("#uname", MySqlDbType.VarChar).Value = usernameInputBox.Text;
// run the first command
cmd2.ExecuteNonQuery();
// Add parameters to the second command
cmd3.Parameters.Add("#uname", MySqlDbType.VarChar).Value = usernameInputBox.Text;
cmd3.Parameters.Add("#upass", MySqlDbType.VarChar).Value = passwordInputBox.Text;
// Run the second command, but this one
// contains two statement, the first inserts, the
// second returns the LAST_INSERT_ID on that table, we need to
// catch that single return
int userID = (int)cmd3.ExecuteScalar();
// Run the third command
// but first prepare the parameters
cmd4.Parameters.Add("#insurance", MySqlDbType.VarChar).Value = nationalInsuranceInputBox.Text;
cmd4.Parameters.Add("#userid", MySqlDbType.Int32).Value = userID;
.... and so on for all other parameters
.... using the appropriate MySqlDbType for the column type
cmd4.ExecuteNonQuery();
}

you current query has an error
string Query4 = "INSERT INTO userdetails (nationalinsurance,userid,forename,middlename,surname,housenumber,street,towncity,postcode,suffix) VALUE ('" + nationalInsuranceInputBox.Text + "','"+"LAST_INSERT_ID()"+"','" + forenameInputBox.Text + "','" + middleNameInputBox.Text + "','" + surnameInputBox.Text + "','" + houseNumberInputBox.Text + "','" + streetTextBox.Text + "','" + towncityTextBox.Text + "','" + postcodeInputBox.Text + "','" + suffixComboBox.Text + "');SELECT LAST_INSERT_ID();"
try the attached query

In your text query string you have: "','"+"LAST_INSERT_ID()"+"','". Note that the "','"s before and after the "LAST_INSERT_ID()" are incorrectly enclosing the LAST_INSERT_ID() term in single quotes.
Try the following query:
string Query4 = "INSERT INTO userdetails (nationalinsurance,userid,forename,middlename,surname,housenumber,street,towncity,postcode,suffix) VALUE ('" + nationalInsuranceInputBox.Text + "',"+"LAST_INSERT_ID()"+",'" + forenameInputBox.Text + "','" + middleNameInputBox.Text + "','" + surnameInputBox.Text + "','" + houseNumberInputBox.Text + "','" + streetTextBox.Text + "','" + towncityTextBox.Text + "','" + postcodeInputBox.Text + "','" + suffixComboBox.Text + "');";

sql missing comma

protected void ImageButton2_Click(object sender, ImageClickEventArgs e)
{
string loginID = (String)Session["UserID"];
string ID = txtID.Text;
string password = txtPassword.Text;
string name = txtName.Text;
string position = txtPosition.Text;
int status = 1;
string createOn = validate.GetTimestamp(DateTime.Now); ;
string accessRight;
if (RadioButton1.Checked)
accessRight = "Administrator";
else
accessRight = "Non-administrator";
if (txtID.Text != "")
ClientScript.RegisterStartupScript(this.GetType(), "yourMessage", "alert('" + ID + "ha " + password + "ha " + status + "ha " + accessRight + "ha " + position + "ha " + name + "ha " + createOn + "');", true);
string sqlcommand = "INSERT INTO USERMASTER (USERID,USERPWD,USERNAME,USERPOISITION,USERACCESSRIGHTS,USERSTATUS,CREATEDATE,CREATEUSERID) VALUES ("+ ID + "," + password + "," + name + "," + position + "," + accessRight + "," + status + "," + createOn + "," +loginID+ ")";
readdata.updateData(sqlcommand);
}
I am passing the sqlcommand to readdata class for execute..and its throw me this error..
ORA-00917: missing comma
Description: An unhandled exception occurred during the execution of
the current web request. Please review the stack trace for more
information about the error and where it originated in the code.
Exception Details: System.Data.OleDb.OleDbException: ORA-00917:
missing comma.
The readdata class function code as below.
public void updateData(string SqlCommand)
{
string strConString = ConfigurationManager.ConnectionStrings["SOConnectionString"].ConnectionString;
OleDbConnection conn = new OleDbConnection(strConString);
OleDbCommand cmd = new OleDbCommand(SqlCommand, conn);
OleDbDataAdapter daPerson = new OleDbDataAdapter(cmd);
conn.Open();
cmd.ExecuteNonQuery();
}

Given that most of your columns are variable-length character, they must be enclosed in single quotes.
So, instead of:
string sqlcommand = "INSERT INTO myTable (ColumnName) VALUES (" + InputValue + ")";
You would, at minimum, need this:
string sqlcommand = "INSERT INTO myTable (ColumnName) VALUES ('" + InputValue + "')";
The result of the first statement, for an InputValue of "foo", would be:
INSERT INTO myTable (ColumnName) VALUES (foo)
which would result in a syntax error.
The second statement would be formatted correctly, as:
INSERT INTO myTable (ColumnName) VALUES ('foo')
Additionally, this code seems to be using values entered directly by the user, into txtID, txtPassword, and so on. This is a SQL Injection attack vector. Your input needs to be escaped. Ideally, you should use parameterized queries here.
This appears to be c#. Please update your tags accordingly.
At any rate, if it is .Net, here is some more information about parameterizing your queries:
OleDbCommand.Parameters Property
OleDbParameter Class

Try this
string sqlcommand = "INSERT INTO USERMASTER (USERID,USERPWD,USERNAME,USERPOISITION,USERACCESSRIGHTS,USERSTATUS,CREATEDATE,CREATEUSERID) VALUES ('"+ ID + "','" + password + "','" + name + "','" + position + "','" + accessRight + "','" + status + "','" + createOn + "','" +loginID+ "')";

Concatenating the query and executing it is not reccomended as it may cause strong SQl Injection. Suppose if any one of those parameters contain a comma(,) like USERPWD=passwo',rd then query will devide it as passwo and rd by the comma. This may be a problem
It is recommended that you use "Parameterized queries to prevent SQL Injection Attacks in SQL Server" and hope it will resolve your issue.
Your code can be rewritten as follows
protected void ImageButton2_Click(object sender, ImageClickEventArgs e)
{
string loginID = (String)Session["UserID"];
string ID = txtID.Text;
string password = txtPassword.Text;
string name = txtName.Text;
string position = txtPosition.Text;
int status = 1;
string createOn = validate.GetTimestamp(DateTime.Now); ;
string accessRight;
if (RadioButton1.Checked)
accessRight = "Administrator";
else
accessRight = "Non-administrator";
if (txtID.Text != "")
ClientScript.RegisterStartupScript(this.GetType(), "yourMessage", "alert('" + ID + "ha " + password + "ha " + status + "ha " + accessRight + "ha " + position + "ha " + name + "ha " + createOn + "');", true);
string strQuery;
OleDbCommand cmd;
strQuery = "INSERT INTO USERMASTER(USERID,USERPWD,USERNAME,USERPOISITION,USERACCESSRIGHTS,USERSTATUS,CREATEDATE,CREATEUSERID) VALUES(#ID,#password,#name,#position,#accessRight,#status,#createOn,#loginID)";
cmd = new OleDbCommand(strQuery);
cmd.Parameters.AddWithValue("#ID", ID);
cmd.Parameters.AddWithValue("#password", password);
cmd.Parameters.AddWithValue("#name", name);
cmd.Parameters.AddWithValue("#position", position);
cmd.Parameters.AddWithValue("#accessRight", accessRight);
cmd.Parameters.AddWithValue("#status", status);
cmd.Parameters.AddWithValue("#createOn", createOn);
cmd.Parameters.AddWithValue("#loginID", loginID);
bool isInserted = readdata.updateData(cmd);
}
rewrite your updateData data as follows
private Boolean updateData(OleDbCommand cmd)
{
string strConString = ConfigurationManager.ConnectionStrings["SOConnectionString"].ConnectionString;
OleDbConnection conn = new OleDbConnection(strConString);
cmd.CommandType = CommandType.Text;
cmd.Connection = con;
try
{
con.Open();
cmd.ExecuteNonQuery();
return true;
}
catch (Exception ex)
{
Response.Write(ex.Message);
return false;
}
finally
{
con.Close();
con.Dispose();
}
}

Update query issue C#

string sql = "Update stdrecord set firstname='" + fname + "',lastname='" + lname + "',mobile='" + mob + "',phone='" + phn + "',city='" + city + "',province'" + prov + "'where id='" + id + "'";
error :
System.Data.SqlClient.SqlException: Incorrect syntax
can anybody cor rectify the query ?

Your missing an equal:
"',province = '" + prov + "' where id='" + id + "'";
And do not build SQL-Queries like this. Please use ADO.Net Parameter.

Equal sign is missing:
,province='" + prov + "' where id='" + id + "'";

string sql = "Update stdrecord set firstname='" + fname + "',lastname='" + lname + "',mobile='" + mob + "',phone='" + phn + "',city='" + city + "',province='" + prov + "'where id='" + id + "'";
You miss = after province and there is no space between prov and where !
Also in this case you are open to SqlInjection, please use SqlCommand.Parameters.
The Query should look like this.
string sql = #"Update stdrecord set firstname=#FName ,lastname=#LastName, mobile=#Mobile,
phone=#Phone,city=#City, province=#Province where id=#ID";
This will protect you from SqlInjection and also sql server will cache your query.
To using command Parameters you need to add this code to your SqlCommand
SqlCommand cmd = new SqlCommand(sql, connectionString);
cmd.Parameters.AddWithValue("#FName", fName);
cmd.Parameters.AddWithValue("#LastName", lname );
cmd.Parameters.AddWithValue("#Mobile", mob);
cmd.Parameters.AddWithValue("#Phone", phn);
cmd.Parameters.AddWithValue("#City", city);
cmd.Parameters.AddWithValue("#Province", prov);
cmd.Parameters.AddWithValue("#ID", id);
With this structure you will not have problems like this in future because you will not add + and ' non stop. Also use # when you build string this give you the possibility to write string on more than one line without using +.

Put a space before Where Clause and equal sign in province column, will get work perfectly