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MySQL get value

Since yesterday I am trying to get this value (see image), I have tried to use "mysqlreader, executescalar and more", but I cannot get the number of lines.
What I want to do is this:
If the result is 0 it does nothing, if equal to 1 it must show an image, if greater than 1 it must show another image
ex code 1
private void patient()
{
if (OpenEventMissionData.Rows.Count != 0)
{
foreach (DataGridViewRow row in OpenEventMissionData.Rows)
{
string idevent = row.Cells[1].Value.ToString();
string sql = "SELECT COUNT(*) FROM patient INNER JOIN event WHERE patient.ID_EVENT = " + "'" + idevent + "'" + "AND evento.EVENT_OPEN = 1;";
MySqlConnection connection = new MySqlConnection();
connection.ConnectionString = ConfigurationManager.ConnectionStrings["dbx"].ConnectionString;
MySqlCommand cmd = new MySqlCommand(sql, connection);
connection.Open();
MySqlDataReader reader = cmd.ExecuteReader();
if (reader.HasRows)
{
DataGridViewButtonColumn patient = new DataGridViewButtonColumn();
OpenEventMissionData.Columns.Add(new PatientColumn());
}
}
}
}
I tried adding the code that told me #oldDog, but the result is always 6
ex code 3
NEW EDIT:
In fact 6 lines appear.
phpmyadmin

Your problem here is you are using HasRows. Since you are doing SELECT COUNT(*) you will always have one row which will contain the count, even if the count is zero. Instead you could use:
if (Convert.ToInt32(reader[0]) > 0)

C# Retrieve ALL SQL Query Results

else if (listBox1.SelectedIndex == 1)
{
String sql2 = "SELECT FirstName, LastName FROM Players WHERE Team = 'Milwaukee Bucks'" +
"AND Number < 24";
// command statement
command = new SqlCommand(sql2, cnn);
SqlDataReader reader = command.ExecuteReader();
// Get table values
if (reader.Read())
{
textBox1.Text = reader.GetString(0).ToString() + " " + reader.GetString(1).ToString();
}
cnn.Close();
command.Dispose();
}
Above is a section of my code. I have a list box with options for the user to choose, and based on which item is selected, a display button will run a query and return the results to a textbox.
However, when I run the code I am only getting one result back. The query returns players on the Bucks who have a number less than 24. There should be multiple of them but I am only getting one in my C# application.

You need to use a while loop to read all the lines instead of reading a single line (via Read()).
Microsoft Documentation has an example of how to use the while loop.
StringBuilder sb = new StringBuilder()
while (reader.Read())
{
sb.AppendLine(reader.GetString(0).ToString() + " " + reader.GetString(1).ToString());
}
textBox1.Text = sb.ToString();

C# confirm table row has been deleted from database

I've written a method which will try and delete a row from a db table based on a primary key id. The problem i have is that the try block is always returning "Success" even if a record has already been deleted / or it doesn't exist.
public string delete_visit(int id)
{
string deleteResponse = null;
string cnn = ConfigurationManager.ConnectionStrings[connname].ConnectionString;
using (SqlConnection connection = new SqlConnection(cnn))
{
string SQL = string.Empty;
SQL = "DELETE FROM [" + dbname + "].[dbo].[" + tbname + "] WHERE VisitorNumber = #IDNumber ";
using (SqlCommand command = new SqlCommand(SQL, connection))
{
command.Parameters.Add("#IDNumber", SqlDbType.Int);
command.Parameters["#IDNumber"].Value = id;
try
{
connection.Open();
command.ExecuteNonQuery();
deleteResponse = "Success";
}
catch (Exception ex)
{
deleteResponse = "There was a problem deleting the visit from the database. Error message: " + ex.Message;
}
}
}
return deleteResponse;
}
I want to be able to tell if the row was affected. I can do this in SQL Server Management Studio like so:
DELETE FROM Visits
WHERE VisitorNumber=88;
IF ##ROWCOUNT = 0
PRINT 'Warning: No rows were updated';
So i want to know how do i plug in the ##ROWCOUNT bit into my c# so that i can tell if the row was deleted?
thanks

ExecuteNonQuery() returns an int, indicating how many rows were affected.
So:
int rowsAffected = command.ExecuteNonQuery();
if (rowsAffected == 0)
{
deleteResponse = "No rows affected";
}
The problem is that this number can be influenced based on what the query actually does. Executing triggers or calling stored procedures could mess with the output, changing the affected number of rows. If you really must, then first execute a query where you check that the record with the given ID exists.

skipping rows from table while fetching data from database asp. net C#

fees_structure has 24 "A" Category rows. But when I try to fetch them and print, it only displays 20 or (21 rows sometimes)
Here is my code:
string catA = "SELECT id,fees_name,amount,fee_category FROM fees_structure where fee_category='A' ORDER BY id";
using (SqlCommand scom = new SqlCommand(catA, con))
{
using (SqlDataReader read = scom.ExecuteReader())
{
read.Read();
if (read.HasRows)
{
while (read.Read())
{
feestableA.Append("<tr>");
feestableA.Append("<td>" + read["fees_name"] + "</td>");
feestableA.Append("<td>" + read["amount"] + "</td>");
feestableA.Append("</tr>");
}
plcfeesA.Controls.Add(new Literal { Text = feestableA.ToString() });
plcfeesA.Dispose();
}
}
}

The read() before the while is suspicious. I suspect that is eating one row.
Another possibility for losing rows would be case-sensitive collations -- if the category could be 'a' (or a variant in another encoding). However, this depends on the default or explicit collations used for the column, database, and server.

I dont think this is a C# issue.
Try this
string catA = "SELECT id,fees_name,amount,fee_category FROM fees_structure where fee_category like '%A%' ORDER BY id";
Just see if your results change

Try this. Watch closely, I removed lines of code that were doing stuff you did not want to be done.
string catA = "SELECT id,fees_name,amount,fee_category FROM fees_structure where fee_category='A' ORDER BY id";
using (SqlCommand scom = new SqlCommand(catA, con))
{
using (SqlDataReader read = scom.ExecuteReader())
{
while (read.Read())
{
feestableA.Append("<tr>");
feestableA.Append("<td>" + read["fees_name"] + "</td>");
feestableA.Append("<td>" + read["amount"] + "</td>");
feestableA.Append("</tr>");
}
plcfeesA.Controls.Add(new Literal { Text = feestableA.ToString() });
}
}
}

Getting multiple MySQL Query results on Visual C# Console App

I am trying to print out results from a MySQL query on a Visual C# Console application. I am able to get multiple columns on one line as you can see below, but I am wondering how I can get multiple results (rows). You see, my table holds more records that meet the query criteria. Can someone help me out?
class Program
{
static void Main(string[] args)
{
string ConnectionString = "Server=localhost; Database=world; Uid=root; Pwd=password"; // giving connection string
MySqlConnection connection = new MySqlConnection(ConnectionString);
MySqlCommand cmd = connection.CreateCommand();
cmd.CommandText = "SELECT name, population FROM city where population > 4000000";
try
{
connection.Open();
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
MySqlDataReader reader = cmd.ExecuteReader();
while (reader.Read())
{
Console.WriteLine("City name is: " + reader["name"].ToString() + " " + reader["population"].ToString());
Console.Read();
}
}

Your call to Console.Read() is blocking the while loop, so you're only printing one line to console, and then waiting for user input.
Cheers

You want to remove that Console.Read();, it is blocking your application from continuing on until it reads another character input on the Console.
Other things to consider: Using statements ensure that the unmanaged resources consumed by the MySql objects are released when the objects are no longer in use. Use Parameterized queries (aka Prepared Statements) as they performs better and are more secure.
string sql = "SELECT name, population FROM city WHERE population > #population"
using (var conn = new MySqlConnection(/*Connection String*/))
{
conn.Open();
using (var cmd = new MySqlCommand(sql, conn))
{
cmd.Parameters.AddWithValue("#population", 4000000);
using (var reader = cmd.ExecuteReader())
{
while (reader.Read())
{
Console.WriteLine("City: {0} Population: {1}",
reader["name"], reader["population"]);
}
}
}
}

There may be other ways to do this, but the best way that I know of is loading the datareader into a datatable.
DataTable dt = new DataTable("City");
dt.Fill(reader);
foreach (DataRow row in dt.Rows){
Console.WriteLine("City name is: " + row["name"].ToString() + " " + row["population"].ToString());
Console.Read();
}
EDIT While answering, I realized that the Console.Read() may be the issue. This code will work, but an input to the console will need to be given for each line.