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I have tried MANY suggested solutions from here but nothing seems to work for this problem. I just keep getting this error message when it hits the 'mdr = command.ExecuteReader();' line. Any thoughts please?
try
{
MySqlConnection connection = new MySqlConnection("SERVER=" + server + ";" + "DATABASE=" + database + ";" + "UID=" + uid + ";" + "PASSWORD=" + password + ";");
MySqlCommand command;
MySqlDataReader mdr;
connection.Open();
string ThePID = tbPID.Text;
string TheRound = tbRound.Text;
string CurrentPage = tbCurrentPage.Text;
// SELECT #myvar:= myvalue
string query = "SELECT ImageURL, ProofingText " +
"INTO #ImageURL, #ProofingText " +
"FROM Rounds " +
"WHERE ProjectID = " + ThePID + " " +
"AND CurrentRound = " + TheRound + " " +
"AND Page = " + CurrentPage + ";";
command = new MySqlCommand(query, connection);
mdr = command.ExecuteReader();
mdr.Read();
rtProofing.Text = mdr.GetString("#PRoofingText");
tbURL.Text = mdr.GetString("#ImageURL");
tbImagePage.Text = Path.GetFileName(tbURL.Text);
PageBox.Image = Image.FromFile(tbURL.Text);
connection.Close();
connection.Dispose();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
If you use MySqlConnector, you will get a helpful exception message that explains the problem:
Parameter '#ImageURL' must be defined. To use this as a variable, set 'Allow User Variables=true' in the connection string.
By default, MySQL queries (executed from .NET) can't use user-defined variables. You can relax this limitation by adding Allow User Variables=true to your connection string.
However, this won't fix your underlying problem, which is that this isn't the right way to select data from MySQL.
Firstly, your query is susceptible to SQL injection; you should rewrite it to use parameters as follows:
using (var command = connection.CreateCommand())
{
command.CommandText = #"SELECT ImageURL, ProofingText
FROM Rounds
WHERE ProjectID = #ThePID
AND CurrentRound = #TheRound
AND Page = #CurrentPage;";
commands.Parameters.AddWithValue("#ThePID", ThePID);
commands.Parameters.AddWithValue("#TheRound", TheRound);
commands.Parameters.AddWithValue("#CurrentPage", CurrentPage);
Then, you can retrieve the values with a slight variation on your current code. You must retrieve the values by their column names, which do not have a leading #. You should also check that a row was retrieved by examining the return value of Read():
if (mdr.Read())
{
rtProofing.Text = mdr.GetString("ProofingText");
tbURL.Text = mdr.GetString("ImageURL");
}
Finally, string concatenation is also not the right way to build a connection string. The MySqlConnectionStringBuilder class exists for this purpose; use it.
var builder = new MySqlConnectionStringBuilder
{
Server = server,
Database = database,
UserID = uid,
Password = password,
};
using var connection = new MySqlConnection(csb.ConnectionString);
My SQLite query hangs then locks during my ExecuteNonQuery() in WriteToDB() below. It only seems to lock during the UPDATE and has no problem with the INSERT. This is only running in a single thread. When it hangs, I can see the journal being created in the SQLite database directory as if it keeps trying to write. It throws a SQLiteException with ErrorCode=5, ResultCode=Busy.
public String WriteToDB()
{
String retString = "";
//see if account exists with this email
String sql = "";
bool aExists = AccountExists();
if (!aExists)
{
sql = "INSERT INTO accounts (email, password, proxy, type, description) VALUES ('" + Email + "', '" + Password + "', '" + Proxy + "', 'dev', '" + Description + "');";
retString = "Added account";
}
else
{
sql = "UPDATE accounts SET password='" + Password + "', proxy='" + Proxy + "', description='" + Description + "' WHERE (email='" + Email + "' AND type='dev');";
retString = "Updated account";
}
using (SQLiteConnection dbconn = new SQLiteConnection("Data Source=" + Form1.DBNAME + ";Version=3;"))
{
dbconn.Open();
using (SQLiteCommand sqlcmd = new SQLiteCommand(sql, dbconn))
{
sqlcmd.ExecuteNonQuery(); //this is where it locks. Only on update.
}
}
return retString;
}
//Test to see if Email exists as account
public bool AccountExists()
{
int rCount = 0;
String sql = "SELECT COUNT(email) FROM accounts WHERE email='" + Email + "' AND type='dev';";
using (SQLiteConnection dbconn = new SQLiteConnection("Data Source=" + Form1.DBNAME + ";Version=3;"))
{
dbconn.Open();
using (SQLiteCommand sqlcmd = new SQLiteCommand(sql, dbconn))
{
rCount = Convert.ToInt32(sqlcmd.ExecuteScalar());
}
}
if (rCount > 0)
return true;
return false;
}
Oh man I feel dumb. I thought I posted all relevant code but all the code I posted works just fine. I had:
SQLiteDataReader dbReader = sqlcmd.ExecuteReader()
instead of
using (SQLiteDataReader dbReader = sqlcmd.ExecuteReader())
In another function. I thought it was an issue with the UPDATE because that was the place where the lock took place. Thanks for the responses and hopefully this reminds reminds everyone to use using() blocks with SQLite the first time!
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 + "');";
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();
}
}
i was trying to update two tables at once, but i got some syntax error on update code could u give me some idea? the insert code works perfect and i tried to copy the insert code and edit on update button clicked
here is my code
private void button2_Click(object sender, EventArgs e)
{
System.Data.OleDb.OleDbConnection conn = new System.Data.OleDb.OleDbConnection();
conn.ConnectionString = #"Provider=Microsoft.ACE.OLEDB.12.0;" +
#"Data source= C:\Users\user\Documents\Visual Studio 2010\Projects\WindowsFormsApplication1\WindowsFormsApplication1\crt_db.accdb";
try
{
conn.Open();
String Name = txtName.Text.ToString();
String AR = txtAr.Text.ToString();
String Wereda = txtWereda.Text.ToString();
String Kebele = txtKebele.Text.ToString();
String House_No = txtHouse.Text.ToString();
String P_O_BOX = txtPobox.Text.ToString();
String Tel = txtTel.Text.ToString();
String Fax = txtFax.Text.ToString();
String Email = txtEmail.Text.ToString();
String Item = txtItem.Text.ToString();
String Dep = txtDep.Text.ToString();
String k = "not renwed";
String Remark = txtRemark.Text.ToString();
String Type = txtType.Text.ToString();
String Brand = txtBrand.Text.ToString();
String License_No = txtlicense.Text.ToString();
String Date_issued = txtDate.Text.ToString();
String my_querry = "update crtPro set Name='" + Name + "',AR='" + AR + "',Wereda='" + Wereda + "',Kebele='" + Kebele + "',House_No='" + House_No + "',P_O_BOX='" + P_O_BOX + "',Tel='" + Tel + "',Fax='" + Fax + "',Email='" + Email + "',Item='" + Item + "',Dep='" + Dep + "','" + k + "',Remark='" + Remark + "' where Name='" + Name + "' ";
OleDbCommand cmd = new OleDbCommand(my_querry, conn);
cmd.ExecuteNonQuery();
String my_querry1 = "SELECT max(PID) FROM crtPro";
OleDbCommand cmd1 = new OleDbCommand(my_querry1, conn);
string var = cmd1.ExecuteScalar().ToString();
String ki = txtStatus.Text.ToString();
String my_querry2 = "update crtItemLicense set PID=" + var + ",Type='" + Type + "',Brand='" + Brand + "',License_No='" + License_No + "',Date_issued='" + Date_issued + "' where PID=" + var + "";
OleDbCommand cmd2 = new OleDbCommand(my_querry2, conn);
cmd2.ExecuteNonQuery();
MessageBox.Show("Message added succesfully");
}
catch (Exception ex)
{
MessageBox.Show("Failed due to" + ex.Message);
}
finally
{
conn.Close();
}
The most likely problem based on the little information given (what database are you using for example - SQL Server 2012?), is that the datatype you are providing in the concatenated dynamic sql does not match the datatype of the column in the database. You've surrounded each value with quotes - which means it will be interpreted as a varchar. If you've got a date value in the wrong format (ie if Date_Issued is a date column) or if it is a number column, then it will error.
The solution is to replace your dynamic SQL with a parameterized query eg:
String my_querry = "update crtPro set Name=#name, AR=#ar, Wereda=#Wereda, etc ...";
OleDbCommand cmd = new OleDbCommand(my_querry, conn);
cmd.Parameters.Clear();
cmd.Parameters.AddWithValue("#name", Name);
cmd.Parameters.AddWithValue("#myParam", Convert.ToDateTime(txtDate.Text.Trim()));
...
cmd.ExecuteNonQuery();
You can read about it further here
PS Make sure your parameters are in the same order as they are used in the SQL, because oledbcommand doesn't actually care what you call them. see here