SQLite not inserting into - c#

I have the following code block
SQLiteConnection cnn = new SQLiteConnection("Data Source=" + getDBPath());
cnn.Open();
SQLiteCommand mycommand = new SQLiteCommand(cnn);
string values = "'" + this.section + "','" + this.exception + "','" + this.dateTimeString + "'";
string sql = #"INSERT INTO Emails_Pending (Section,Message,Date_Time) values (" + values + ")";
mycommand.CommandText = sql;
mycommand.ExecuteNonQuery();
cnn.Close();
When I execute it , nothing happens, no errors are produced, but nothing gets inserted, what am I doing wrong?
Path to DB is correct!
Insert statement works, tried it in a SQLLite GUI (no problems there)
Here is the SQL Snippet:
"INSERT INTO Emails_Pending (Section,Message,Date_Time) values ('Downloading Received Messages','Object reference not set to an instance of an object.','04.12.2009 11:09:49');"

How about adding Commit before Close
mycommand.Transaction.Commit();

You should always use transactions and parameterized statements when using sqlite, else the performance will be very slow.
Read here: Improve INSERT-per-second performance of SQLite?
Your approach is vulnerable to sql injection too. A message in an email can have a piece of sql in its body and your code will execute this piece of sql. You can also run into problems when the message in your string values contains a " or a ' .

Related

My query keeps rubbish in my sql table if it will not be complete properly

I'm using a a multiple query with insert and update statement together.
The problem is that if query will not be completed(for some reason e.x bad internet connection) my SQL Server table keeps rubbish.
Example of query:
SqlCommand cmd = new SqlCommand("INSERT INTO CustomerTrans (TableName, UserID, UserName, SumQuantity, SumPrice, SumRealPrice, SumExtrasPrice, SumTotal, SumDiscountTotal, DateTime) SELECT " + Connection.TableName + ",' " + Connection.UserID + "', '" + Connection.Username + "',Sum(Quantity),Sum(Price),Sum(RealPrice),Sum(ExtrasPrice), Sum(Quantity * Price),Sum(Quantity * DiscountPrice),'" + DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss") + "' from InventoryTransTemp where active=1 and TableName=" + Connection.TableName + ";update InventorytransTemp set TrnDocumentID=(select max(TrnDocumentID) from CustomerTrans where UserID='" + Connection.UserID + "'),Active=0 where TableName=" + Connection.TableName + " and Active=1", con);
cmd.ExecuteNonQuery();
Take a photo from a query which has not be completed properly look query 2989 it has NULL values. I want to avoid inserting something if query is not be completed properly.
Sorry for my previous Question it was Unclear
Try it like this:
string sql =
"INSERT INTO CustomerTrans" +
" (TableName, UserID, UserName, SumQuantity, SumPrice, SumRealPrice, SumExtrasPrice, SumTotal, SumDiscountTotal, DateTime)" +
" SELECT #TableName, #UserID, #Username, Sum(Quantity), Sum(Price), Sum(RealPrice), Sum(ExtrasPrice), Sum(Quantity * Price), Sum(Quantity * DiscountPrice), current_timestamp" +
" FROM InventoryTransTemp" +
" WHERE active=1 and TableName= #TableName;\n" +
"SELECT #TranID = scope_identity;\n"
"UPDATE InventorytransTemp" +
" SET TrnDocumentID=#TranID ,Active=0" +
" WHERE TableName= #Tablename and Active=1;";
using (var con = new SqlConnection("connection string here"))
using (var cmd = new SqlCommand(sql, con))
{
//I'm guessing at exact column types/lengths here.
// You should update this to use your exact column types and lengths.
// Don't let ADO.Net try to guess this for you.
cmd.Parameters.Add("#TableName", SqlDbType.NVarChar, 20).Value = Connection.TableName;
cmd.Parameters.Add("#UserID", SqlDbType.Int).Value = Connection.UserID;
cmd.Parameters.Add("#Username", SqlDbType.NVarChar, 20).Value = Connection.Username;
cmd.Parameters.Add("#TranID", SqlDbType.Int).Value = 0; //placeholder only
con.Open();
cmd.ExecuteNonQuery();
}
Note the improved formatting of the query, the use of scope_identity() to get the new identity value rather than a nested select statement that might not be atomic, that I avoided ALL uses of string concatenation to substitute data into the query, that I avoided the AddWithValue() method entirely in favor of an option that doesn't try to guess at your parameter types, and the use of using blocks to be sure the SqlClient objects are disposed properly.
The only thing I'm still concerned about is if your INSERT/SELECT operation might create more than one new record. In that case, you'll need to handle this a different way that probably involves explicit BEGIN TRANSACTION/COMMIT statements, because this code only gets one #TranID value. But in that case, the original code was broken, too.

execute sql command in asp.net

I have a problem with executing a sql command to the DB. The command should add a new user to the 'users' table.
But when I run the code, I get this Exception on:
command.ExecuteNonQuery();
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: Syntax error in INSERT INTO statement.
this is the code of the page - GetSignIn.cshtml :
#{
string Uname = Request["name"];
string userName = Request["userName"];
string pass = Request["passWord"];
string pic = Request["pic"];
string privacy = Request["privacy"];
if(pic == null)
{
pic = "Shared/defaultPic.jpg";
}
System.Data.OleDb.OleDbConnection connection = new System.Data.OleDb.OleDbConnection();
connection.ConnectionString = #"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Users\Etay\Documents\Visual Studio 2012\WebSites\Josef\Shared\users.mdb";
try
{
System.Data.OleDb.OleDbCommand command = new System.Data.OleDb.OleDbCommand();
command.Connection = connection;
connection.Open();
command.CommandText = "INSERT INTO users (userName,passWord,Uname,pic) VALUES ('" + userName + "', '" + pass + "', '" + Uname + "', '" + pass + "', " + pic + ")";
command.ExecuteNonQuery();
Response.Redirect("../HtmlPage.html");
}
finally
{
connection.Close();
}
}
What should I change in my code? Why is it happening? Where is the syntax error in the INSERT INTO?
Use parameterized queries. Here is your statement rewritten to make use of them.
I replaced your try/finally with a using block although your try/finally was acceptable.
Parameterized queries prevent errors and Sql Injection Attacks. An error could occur in your existing code if I were to submit a tick as a part of my user name or password. In the current form this would result in an exception. This is because the tick character is used to quote strings in sql syntax.
using (System.Data.OleDb.OleDbConnection connection = new System.Data.OleDb.OleDbConnection())
{
connection.ConnectionString = #"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Users\Etay\Documents\Visual Studio 2012\WebSites\Josef\Shared\users.mdb";
using (System.Data.OleDb.OleDbCommand command = new System.Data.OleDb.OleDbCommand())
{
command.Connection = connection;
command.CommandText = "INSERT INTO users (userName,passWord,Uname,pic) VALUES (?,?,?,?)";
command.Parameters.Add(userName);
command.Parameters.Add(pass);
command.Parameters.Add(Uname);
command.Parameters.Add(pic);
connection.Open();
command.ExecuteNonQuery();
}
}
About parameters for an OleDb connection from OleDbCommand.Parameters
Remarks
The OLE DB .NET Provider does not support named parameters for passing parameters to an SQL statement or a stored procedure called by an OleDbCommand when CommandType is set to Text. In this case, the question mark (?) placeholder must be used. For example:
SELECT * FROM Customers WHERE CustomerID = ?
Therefore, the order in which OleDbParameter objects are added to the OleDbParameterCollection must directly correspond to the position of the question mark placeholder for the parameter in the command text.
What should I change in my code?
Change to parameters (that also fixes the problem that you don;t have quotes around the pic value)
Remove the second instance of pass in your values
command.CommandText = "INSERT INTO users (userName,passWord,Uname,pic) VALUES (#userName, #pass, #Uname, #pic)";
command.Parameters.Add("#userName").Value = userName;
.. etc.
It's unclear what the type if pic is - you are passing a string but I can;t tell of the column stores a file path or if you are indending to serialize the file and store it in a pinary field.
You set 4 fields after the "INTO" clause, however you're passing 5 parameters:
"INSERT INTO users (userName,passWord,Uname,pic) VALUES ('" + userName + "', '" + pass + "', '" + Uname + "', '" + pass + "', " + pic + ")";
Just add the fifth field, or remove one parameter from the VALUES part
Please check take a look at your Insert statement, it looks like that you provided password value twice.
The number of query values and the destination fields should be same in an INSERT statement.
You have the wrong number parameters in your insert statement. For clarity, why not use string.Format to keep everything uniform? (Assuming these are all string types)
var rawSql = #"Insert INTO Users (userName,passWord,Uname,pic) VALUES ('{0}','{1}','{2}','{3}')";
command.CommandText = string.Format(rawSql, userName, pass, Uname, pic);
command.ExecuteNonQuery();
However, it also looks like you probably want to include that 5th parameter as well - just extend the format :
var rawSql = #"Insert INTO Users (userName,passWord,Uname,pic, privacy) VALUES ('{0}','{1}','{2}','{3}','{4}')";
command.CommandText = string.Format(rawSql, userName, pass, Uname, pic, privacy);
command.ExecuteNonQuery();
Since most of the answers failed to address the SQL Injection vulnerability, here's an example with parameterized queries. In addition to preventing SQL Injection attacks, it also makes it easier to troubleshoot these types of issues, and you don't need to worry about quoting or not quoting parameters.
System.Data.OleDb.OleDbConnection connection = new System.Data.OleDb.OleDbConnection();
connection.ConnectionString = #"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Users\Etay\Documents\Visual Studio 2012\WebSites\Josef\Shared\users.mdb";
try
{
System.Data.OleDb.OleDbCommand command = new System.Data.OleDb.OleDbCommand();
command.Connection = connection;
connection.Open();
command.CommandText = "INSERT INTO users (userName, passWord, Uname, pic, privacy) VALUES (?, ?, ?, ?, ?)";
command.Parameters.Add(userName);
command.Parameters.Add(pass);
command.Parameters.Add(name);
command.Parameters.Add(pic);
command.Parameters.Add(privacy);
command.ExecuteNonQuery();
Response.Redirect("../HtmlPage.html");
}
finally
{
connection.Close();
}
Tnx 4 the help
It happend to be a problem with the database - you can not apply a INSERT INTO statement where the column name is "password". "password" is a Reserved word
in SQL.
Tnx again,
Etay

Error when trying to insert into MS Access Database

I am developing a program that uses a relational database. In one particular form I am trying to insert new products information into the database.
using System.Data.OleDb;
When I try to save a new product this code runs...
connection.Open();
OleDbCommand command = new OleDbCommand();
command.Connection = connection;
string query = "insert into Products (ProductName,ProductSKU,RP,WP,Stock,FPS,Ammo,MagazineCap,HopUp,Range,Brand,Colour,Action,Features) values('" + txt_ProductName.Text + "','" + txt_SKU.Text + "'," + txt_RP.Text + "," + txt_WP.Text + "," + numericUpDown_Inventory.Value + "," + cobo_FPS.Text + ",'" + cobo_Ammo.Text + "'," + cobo_MagazineCap.Text + ",'" + cobo_HopUp.Text + "'," + cobo_Range.Text + ",'" + cobo_Brand.Text + "','" + cobo_Colour.Text + "','" + cobo_Action.Text + "','" + txt_Features.Text + "')";
//Action field currently causes an error
MessageBox.Show(query);
command.CommandText = query;
command.ExecuteNonQuery();
connection.Close();
...and an error is thrown
"Error System.Data.OleDb.OleDbException (0x80040E14): Syntax error in
INSERT INTO statement."
(and then a bunch of stuff which I don't think is important)
Apologies for the HUGE SQL query. I am using the exact same method of using the insert SQL query in several other places in my program and they all work completely fine. This example however is causing this error. Through the tedious process of "commenting out" individual parts of my SQL query I found that the error lies with the "Action" field. I have checked that the data type in my database is correct and that I am using the '' punctuation to surround the text string that is being inserted into the database.
I think I've checked everything, so why am I still getting this error?
Many thanks in advance and if more information is required just let me know ;)
Action is a reserved keyword in OLE DB Provider. You need to use it with square brackets like [Action]. As a best practice, change it to non-reserved word.
But more impontant
You should always use parameterized queries. This kind of string concatenations are open for SQL Injection attacks.
Also use using statement to dispose your OleDbConnection and OleDbCommand automatically instead of calling .Close() method manually.

Syntax error in UPDATE statement OleDb Exception

I check my SQL Statement many times and it seems that my SQL Statement is Error. I don't why it doesn't work. My SQL Statement is correct and It resulted to this OleDBException "Syntax error in UPDATE statement.".
Here is the code
OleDbConnection CN = new OleDbConnection(mysql.CON.ConnectionString);
CN.Open();
cmd1 = new OleDbCommand("Update Mosque Set Name='" + txtNAME.Text + "', No='" + Convert.ToInt32(txtNO.Text) + "', place='" + txtPlace.Text + "', group='" + txtGroup.Text + "', description='" + txtdec.Text + "' where id='" + txtID.Text + "'", CN);
cmd1.ExecuteNonQuery();
CN.Close();
need help please to know what is the error here
I don't know what database are you using, but I am sure that GROUP is a reserved keyword in practically any existant SQL database. This word cannot be used without some kind of delimiter around it. The exact kind of delimiter depend on the database kind. What database are you using?
Said that, please do not use string concatenation to build sql commands, but use always a parameterized query. This will allow you to remove any possibilities of Sql Injection and avoid any syntax error if one or more of your input string contains a single quote somewhere
So, supposing you are using a MS Access Database (In Access also the word NO is a reserved keyword and the delimiters for reserved keywords are the square brakets) you could write something like this
string commandText = "Update Mosque Set Name=?, [No]=?, place=?, " +
"[Group]=?, description=? where id=?"
using(OleDbConnection CN = new OleDbConnection(mysql.CON.ConnectionString))
using(OleDbCommand cmd1 = new OleDbCommand(commandText, CN))
{
CN.Open();
cmd1.Parameters.AddWithValue("#p1",txtNAME.Text);
cmd1.Parameters.AddWithValue("#p2",Convert.ToInt32(txtNO.Text));
cmd1.Parameters.AddWithValue("#p3",txtPlace.Text);
cmd1.Parameters.AddWithValue("#p4",txtGroup.Text);
cmd1.Parameters.AddWithValue("#p5",txtdec.Text);
cmd1.Parameters.AddWithValue("#p6",txtID.Text);
cmd1.ExecuteNonQuery();
}
Instead for MySQL you have to use the backticks around the GROUP keyword
string commandText = "Update Mosque Set Name=?, No=?, place=?, " +
"`Group`=?, description=? where id=?"
Hard to tell without knowing the values of the texboxes, but I suspect that one of them has an apostrophe which is causing an invalid syntax.
I recommend using parameters instead:
cmd1 = new OleDbCommand("Update Mosque Set [Name]=#Name, [No]=#No, [place]=#Place, [group]=#Group, [description]=#Description WHERE id=#ID", CN);
cmd1.Parameters.AddWithValue("#Name",txtNAME.Text);
cmd1.Parameters.AddWithValue("#No",Convert.ToInt32(txtNO.Text));
// etc.

Is there a way of creating a database in MYSQL without using SMO in C#

I'm trying to create a database through C# without using SMO, is it possible?! I've got this at the moment but I'm 99% it's wrong;
connectionString2 = "SERVER=" + server + ";" + "DATABASE=master;"
+ "UID=" + uid + ";" + "PASSWORD=" + password + ";"
this.OpenConnection(); //Which opens the above connection
// The Lines array has stored the sql statements to create the databse
// and tables for that database
foreach (string line in lines)
{
create_database += line;
}
MySqlCommand cmd = new MySqlCommand(create_database, connection2);
cmd.ExecuteNonQuery();
is it actually possible do this without using SMO?!
You have to use MySqlCommand as you're doing in the example.
MySqlCommand cmd = new MySqlCommand("CREATE DATABASE YAYNEWDATABASE;", connection2);
connection2.Open();
cmd.ExecuteNonQuery();
connection2.Close();
Alternatively if you're going to be doing a lot of modification I'd suggest trying a tool like Manatee to handle your database creation/migration as part of a build script. This is making a lot of assumptions about what you're doing, but it doesn't hurt to be aware of it.
This adds migrations similar to those in rails to .net.
{
up: "CREATE TABLE Orders (ID {pk}, OrderNumber {string} NOT NULL, SubTotal {money})",
down: "DROP TABLE Orders"
}
You might use something like this:
var connection = new MySqlConnection("Data Source=server;UserId=root;PWD=pass;");
var command = new MySqlCommand("CREATE DATABASE FancyDatabase;", connection);
connection.Open();
command.ExecuteNonQuery();
connection.Close();
Note: there is no default database, and you need to have the rights. And: this is untested code, uses standard sql features.

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