Question about adding to database from text entered into textbox - c#

I have an app that displays data from a sql database in a datagrid. I am adding a feature that will allow a user to add a new item to this datagrid. I will have an Add button in the app that when clicked, will open a new window where all the info will be added. After the user inputs the info into the text boxes and clicks save, that info gets saved to the database. This will require inserting data into two separate tables that are related. The first table is ItemDescriptor and the other table is Accessories. The id for ItemDescriptor has to be put into the Accessories table as ItemDescriptorID. I have tried to do two separate insert queries but cant figure out how to get the id from ItemDescriptor into the Accessories table programatically. Sorry, I know this might be a little confusing. Let me know if more info is needed. Thanks
_dbAccess.ExecuteNonQuery("INSERT INTO ItemDescriptor (id, Model, Brand, DeviceName, Type, Notes) VALUES ('" + System.Guid.NewGuid() + "', '" + tbModel.Text + "', '" + tbBrand.Text + "', '" + tbDeviceName.Text + '", '" + cmbType.SelectedValue + "', '" + tbNotes.Text + "')");
_dbAccess.ExecuteNonQuery("INSERT INTO Accessories (id, ItemDescriptorID, StorageRoomCount, OnHandCount, HiBayCount) VALUES ('" + System.Guid.NewGuid() + "', '" +
and thats about as far as i got...not sure how to get the ItemDescriptorID in there from the first query.

First, please please please use parameterized queries when dealing with user-supplied input. That string concatenation stuff is just asking for a SQL injection attack.
Second of all, if you're using SQL Server, you can use something like ##IDENTITY to get the identity field after insertion. There's something comparable on all systems, so if you let us know what you're using we can point you in the right direction.

I'm assuming that you're using SQL Server and that ItemDescriptor.id is an identity column; correct?
If you execute the following command immediately after your initial insert statement, it will return the value of the most recently generated identity:
var newID = _dbAccess.ExecuteScalar("SELECT Scope_Identity()");
You can use newID to construct your second insert statement.
One caveat: The SELECT Scope_Identity() statement must be executed on the same connection instance as the initial insert statement. So ensure that you're not closing and reopening your connection between statements. If this seems to be a problem, you can actually combine your insert and select statements into a single command; e.g.:
var newID = _dbAccess.ExecuteScalar("INSERT [all your code here]; SELECT Scope_Identity();");
Good luck!

Check out this site about Getting the identity of the most recently added record

I figured out a way to make it work. I just made the guid an object and then used it as a variable and that worked. thanks for all the suggestions.
Guid guid = System.Guid.NewGuid();
if (_dbaccess != null)
{
_dbAccess.ExecuteNonQuery("INSERT INTO ItemDescriptor (id, Model, Brand, DeviceName, Type, Notes) VALUES ('" + guid + "', '" + tbModel.Text + "', '" + tbBrand.Text + "', '" + tbDeviceName.Text + '", '" + cmbType.SelectedValue + "', '" + tbNotes.Text + "')");
_dbAccess.ExecuteNonQuery("INSERT INTO Accessories (id, ItemDescriptorID, StorageRoomCount, OnHandCount, HiBayCount) VALUES ('" + System.Guid.NewGuid() + "', '" + guid + "', '" + tbStorageRoom.Text + "', '" + tbOnHand.Text + "', '" + tbHiBay.Text + "')");
}

Related

programming for keyword search from database?

Hello I have a table with following columns.
Profile_ID,
Name,
Age,
More_Info_about family,
qualification details,
job details and
partner_preference
I have to search on keyword basis and keyword is to be taken from textbox.
The search result should be in such a way so that if keyword presents in starting, ending and in between the sentence of any of the columns presents in where conditions.
I tried LIKE '" + txtbox_keyword.Text + "'
but is not working properly it is not searching data if keyowrd is present in between sentense.
select (Profile_ID,Name,Age, More_info_about_family,Job_Business_Location_City,Salary
from tblRegistration
WHERE More_info_about_family LIKE '" + txtbox_keyword.Text + "'
OR LIKE '" + txtbox_keyword.Text + "'
OR origin LIKE '" + txtbox_keyword.Text + "'
OR Job_Detail LIKE '" + txtbox_keyword.Text + "' ", con);
Use sqlParameter for except sql injection and you need add %% in your query to search by field.
SqlParameter parameter = new SqlParameter("#keyWord",txtbox_keyword.Text);
select (Profile_ID,Name,Age, More_info_about_family,Job_Business_Location_City,Salary
from tblRegistration
WHERE More_info_about_family LIKE '%#keyWord%'
OR LIKE '%#keyWord%'
OR origin LIKE '%#keyWord%'
OR Job_Detail LIKE '%#keyWord%', con,parameter);

Incorrect string value(C# Visual Studio 2015, MySQL Server 5.5(Console))

I need help! I write software for database management for the course. I can not complete the transaction by inserting data. I am from Ukraine and use Ukrainian data on database, but the transaction is not completed bringing the error "Incorrect string value: '\ xD0 \ xB2' for column 'User_name' at row 1 "} System.Exception {MySql.Data .MySqlClient.MySqlException}
" I read all the articles on the stack overflow but nothing helped me(
i use SET NAMES 'utf8'(cp1251, utf8mb4, koi8r, win1251, cp866 and other) but nothing work(help, the problem may be encoded on the development environment?
i use MySql.Data.MySqlClient or MySQL.dll
connect code ->
connStr = "server= localhost;user=root;charset=utf8mb4;database=DB_Journal;port=3306;password=masterkey;"conn = new MySqlConnection(connStr);
and insert ->
conn.Open();
string sql = "insert into Users(User_id, User_name, User_surname, User_fname, Login, UType_id, Password,Secret,Answer) values (null, '" +
textBox1.Text + "', '" + textBox2.Text + "', '"
+ textBox4.Text + "', '" + textBox3.Text + "', '"
+ usr + "', '" + pass + "', '"
+ richTextBox1.Text + "', '"
+ textBox7.Text + "')";
MySqlCommand cmd = new MySqlCommand(sql, conn);
cmd.ExecuteNonQuery();
(I'm sorry, I can write not correctly, but i study hard)
I don't know what you are trying to accomplish with SET NAMES, but it probably does not do what you think it does. (Besides, its documentation explicitly says that it won't work with utf8.)
It is kind of hard to tell without seeing your CREATE TABLE statement, but what is probably happening is that you have declared your User_name etc. columns as being of type CHAR or VARCHAR while in fact they should be of type NCHAR or NVARCHAR.

Inserting data via C# is inaccessible when queried

I am having a very annoying issue with a program I am currently making. In the program a teacher with admin status can add a user to a students_tbl Table in an SQL database by adding in relevant information. The following code adds a Student to the student_tbl in C#.
string studentAdd = "Insert Into student_tbl(Forename, Surname, SchlYear, InOrOut, Block1, Block2, Block3, Block4, Pword) Values (#forename, #surname, '" + SchlYear + "', '" + inOrOut + "' , '" + Blocks[0] + "', '" + Blocks[1] + "', '" + Blocks[2] + "', '" + Blocks[3] + "', #password)";
SqlCommand studentAddCommand = new SqlCommand(studentAdd, con);
studentAddCommand.Parameters.Add(new SqlParameter("#forename", Forename));
studentAddCommand.Parameters.Add(new SqlParameter("#surname", Surname));
studentAddCommand.Parameters.Add(new SqlParameter("#password", hashedPassword));
studentAddCommand.ExecuteNonQuery();
MessageBox.Show("Student Added Successfully");
con.Close();
The variables added in to the table come from results and are simply just names, integers and bools, nothing complex.
The issue I am having is that this data is inaccessible when trying to log in as a student added via this system. If a user is added manually through SSMS then it works fine. Is this something ridiculously basic I am missing, as if I was to add a user ie. 'Joe Bloggs', and search
Select UserID from student_tbl Where Forename = 'Joe'
It simply finds nothing.
Does anybody have any glaring issues I am missing, or not declaring etc? I am able to provide any more information if it could lead to a solution. Thanks.
According to #Jeroen van Langen comment, try to trim values:
studentAddCommand.Parameters.Add(new SqlParameter("#forename", Forename.Trim()));
studentAddCommand.Parameters.Add(new SqlParameter("#surname", Surname.Trim()));

C# MySQL Error “Column count doesn't match value count at row 1”

MySqlCommand cmd1 =
new MySqlCommand(
"INSERT INTO quotedetails (name, address, district, date, forto, refto, total) VALUES('" + txttoname.Text + "', '" + txttoaddress.Text.Replace("\r\n", "<br />").ToString() + "', '" + txtdistrict.Text + "' , '" + dateTimePicker1.Value.Date.ToString("yyyy-MM-dd") +"', '" + txtfor.Text + "', '" + txtref.Text + "', '" + txttotal.Text + "')", conn);
{
Can I get some help please? Im getting Column count doesn't match value count at row 1 when the command1 is executed.
You should never use SQLs like this. It is prone to SQL Injection attacks. When you use it like yours, one can steal confidential information from database or even delete your tables, data etc. For details please read SQL Injection on wiki
Instead you should use parameterized SQL queries. In that way you are safe from injection attacks and I believe it is much more practical to write sql.
In your case entering single ' char into one of the textboxes will cause your query to get exception. To fix the issue just use prameters.
For your case you can write something like that.
string sqlString = #"INSERT INTO quotedetails (
name,
address,
district,
date,
forto,
refto,
total)
VALUES (
#PAR_name,
#PAR_address,
#PAR_district,
#PAR_date,
#PAR_forto,
#PAR_refto,
#PAR_total)";
MySqlCommand cmd1 = new MySqlCommand(sqlString, conn);
cmd1.Parameters.AddWithValue("PAR_name", txttoname.Text);
cmd1.Parameters.AddWithValue("PAR_address", txttoaddress.Text.Replace("\r\n", "<br />"));
cmd1.Parameters.AddWithValue("PAR_district", txtdistrict.Text);
cmd1.Parameters.AddWithValue("PAR_date", dateTimePicker1.Value.Date);
cmd1.Parameters.AddWithValue("PAR_forto", txtfor.Text);
cmd1.Parameters.AddWithValue("PAR_refto", txtref.Text);
cmd1.Parameters.AddWithValue("PAR_total", txttotal.Text);
Please note that I use prefix PAR_ for my sql parameters, it is just a convention you can use that or skip PAR_ prefix does not matter and it is all about naming habits.
Additionaly; in a parameterized query, you don't need to convert all your values to string. You can use DateTime for your date field or you can pass int variable without using ToString() as you do before.
On the face of it, this happens when the number of values are more or less than columns provided.
From your statement, this does not seem to be the case. BUT since you are providing uielements directly into insert statement (Textbook case of SQL Injection), I am guessing there is a single quote ' in any of your ui elements, which breaks your insert statement.
MySqlCommand cmd1 = conn.CreateCommand();
cmd1.CommandText = "INSERT INTO quotedetails (name, address, district, date, forto, refto, total) VALUES('" + txttoname.Text + "', '" + txttoaddress.Text.Replace("\r\n", "<br />").ToString() + "', '" + txtdistrict.Text + "', '" + dateTimePicker1.Value.Date.ToString("yyyy-MM-dd") +"', '" + txtfor.Text + "', '" + txtref.Text + "', '" + txttotal.Text + "')";
Using SQL parameters will save you from lots of trouble as well as SQL injection.I am quite sure that if you use parameters your problem will be resolved:
MySqlCommand cmd1 = new MySqlCommand( "INSERT INTO quotedetails (name, address, district, date, forto, refto, total) VALUES(#name,#address,#district,#date,#forto,#refto,#total)", conn);
cmd1.Parameters.AddWithValue("#name",txttoname.Text);
cmd1.Parameters.AddWithValue("#address",+ txttoaddress.Text.Replace("\r\n", "<br />").ToString());
cmd1.Parameters.AddWithValue("#district",txtdistrict.Text);
...

Incorrect syntax in T-SQL statement in c#

I have the following code:
USE [DB] INSERT INTO Extract2_EventLog VALUES (" + li.userId + ", '" + li.startTime.ToString() + "', '" + li.endTime.ToString() + "', '" + li.elapsedTime.ToString() + (li.actionType == ActionType.REPORT ? "', 'report')" : "', 'extract')', '" + status + "'");
When I run this, I get the following error:
{"Incorrect syntax near ', '.\r\nUnclosed quotation mark after the
character string ''."}
I can't see what I'm doing wrong.. Anyone?
Man....Where to start with this...
First off, you should be using stored procedures that accept parameters (variables from your application code). Second, you should have a dataaccess layer in your application separating database calls and your user interface. I can't possible stress enough how important this is and how bad your current approach is. You will forever be fighting problems like this until you correct it.
But to address the question as it was asked...Your error is because your query string is malformatted. Use the debugging tools to view the string before it is sent to the database and then you should be able to quickly determine what is wrong with it. To troubleshoot, you can always cut and paste that string into SSMS, refine it there, and then make the necessary changes to your c# code.
First of all look at the answer of Stan Shaw, next take a look at the comment of Jon Skeet!
The first thing to do is stop building SQL like that... right now. Use parameterized SQL and you may well find the problem just goes away... and you'll be preventing SQL Injection Attacks at the same time.
They sayed everything that's important and just for the sake of giving you a direct answer:
You have a status + "'"); at your code which needs to be changed to status + "')"; ...
...like this one:
string statement = "USE [DB] INSERT INTO Extract2_EventLog VALUES (" + li.userId + ", '" + li.startTime.ToString() + "', '" + li.endTime.ToString() + "', '" + li.elapsedTime.ToString() + (li.actionType == ActionType.REPORT ? "', 'report')" : "', 'extract')', '" + status + "')";
Instead of concatenating values into your query you should use a parameterized query or a stored procedure.
A rewrite of your code could be something like (depending on datatypes, etc):
string commandText = "INSERT INTO Extract2_EventLog (userId, startTime, endTime, elapsedTime, actionType, [status]) VALUES (#userId, #startTime, #endTime, #elapsedTime, #actionType, #status)";
using (SqlConnection connection = new SqlConnection(connectionString))
{
SqlCommand command = new SqlCommand(commandText, connection);
command.Parameters.AddWithValue("#userId", li.userId);
command.Parameters.AddWithValue("#startTime", li.startTime);
command.Parameters.AddWithValue("#endTime", li.endTime);
command.Parameters.AddWithValue("#elapsedTime", li.elapsedTime);
command.Parameters.AddWithValue("#actionType", li.actionType == ActionType.REPORT ? "report" : "extract");
command.Parameters.AddWithValue("#status", status);
connection.Open();
int rowsAffected = command.ExecuteNonQuery();
Console.WriteLine("RowsAffected: {0}", rowsAffected);
}
You've forgot the " at the beginning. So your code reverts sql with non sql.
AND your example seems to be incomplete.

Categories

Resources