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How to get fields from database [closed]

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I want to get "Model" field and put on Textbox6. But how come it does not work.
The problem is that the Model field answer will not be shown in the textbox6
string Query = "Select * from S where Name = '" + TextBox1.Text + "' and Clientno = '" + TextBox2.Text + "';";
command.CommandText = Query;
OleDbDataReader reader = command.ExecuteReader();
while (reader.Read())
{
string Model = reader.GetString(reader.GetOrdinal("Model"));
TextBox6.Text = Model;
}

Couple of things:
Do not use select *, instead use select your columns names
Do not pass the .Text directly to your query, instead use parameterized sql expression
If Clientno is primary key column or , combination of Name and ClientNo gives unique result, use ExecuteScalar, you don't have to use ExecuteReader and loop through the datareader
Since you using only one field and want to fill in the textbox, modify your select statement to :
select top 1 Model from S where....
And if you are reading only one row you will not need a while loop. Further, you should always close the reader and put your SqlConnection inside using block. ( edited as suggested by the comments)
If (reader.Read())
{
TextBox6.Text = reader.GetString(reader.GetOrdinal("Model"));
reader.Close();
}

Must find out if now is the change than the one who is in the database [closed]

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It is such that I have no date in the database, and if it is less than the time / date as we have now so it must go in and refresh the use of the will rank 2. This means that we have, for example. the time is now and if it is not right than he who is in the database so it should not go in and do anything at all.
That means if the date looks like this is it too old.
3/15/2015 09:34:42 AM (it is now.) and 3/15/2015 04:34:42 AM
So it must go into the code to update the user to get rank 2
while (readerBrugere.Read())
{
string brugerid = readerBrugere["id"].ToString();
DateTime brugerdato = Convert.ToDateTime(readerBrugere["trydato"].ToString());
conn1.Close();
if (Convert.ToDateTime(DateTime.Now.ToString("ddmmyyyyHHmmss")) > Convert.ToDateTime(brugerdato))
{
int rankid = 2;
cmd1.CommandText = "UPDATE brugere SET rank = #rank WHERE Id = #brugerid;";
cmd1.Parameters.AddWithValue("#rank", rankid);
cmd1.Parameters.AddWithValue("#brugerid", brugerid);
conn1.Open();
cmd1.ExecuteNonQuery();
conn1.Close();
}
}
It will only run content through if it is to time with me is right than what is in the database

The text of your question hard to decipher, but looking at the code I can suggest a much-improved version:
while (readerBrugere.Read())
{
//if these columns cannot be null, you should be able to use a simple cast
int brugerid = (int)readerBrugere["id"];
DateTime brugerdato = (DateTime)readerBrugere["trydato"];
//don't close your database connection here
//These values are *already* datetimes. There's not need to convert to datetime
// and *especially* no need to convert to strings to compare them
if (DateTime.Now > brugerdato)
{
// the "2" is a constant: just code it into the query that way
string sql = "UPDATE brugere SET rank = 2 WHERE Id = #brugerid;";
//or maybe you wanted this instead:
string sql = "UPDATE brugere SET rank = rank + 1 WHERE Id = #brugerid;";
//AddWithValue() kinda sucks somtimes. I prefer to do it like this instead:
cmd1.Parameters.Add("#brugerid", SqlDbType.Int).Value = brugerid;
//don't use the same connection as you did for the outer query:
using (var cn2 = new SqlConnection(conn1.ConnectionString))
using (var cmd2 = new SqlCommand(sql, cn2))
{
cmd2.ExecuteNonQuery();
}
}
}
Finally, all this is really moot, as I expect you can do this entire process in the database with a single query:
UPDATE brugere
SET rank = rank + 1
WHERE trydato <= current_timestamp AND brugerdi IN
(
...existing query goes here, but only select the brugerdi column ...
)

How to conditionally validate SQL data in C# [closed]

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I have this code
public static DataSet tipopromocion(string id_edificio,string date_from, string date_to)
{
DataSet tipo = new DataSet();
MySqlConnection con = new MySqlConnection(connectionstring);
string tipo_promo = "select pr.tipo_promocion from promocion_edificio pe inner join inventario i on i.id_edificio = pe.id_edificio inner join promocion pr on pe.id_promocion=pr.id_promocion where i.id_edificio = '" + id_edificio + "' and i.fecha between '" + date_from + "' and Date_Sub('" + date_to + "',interval 1 Day) and i.fecha between pe.inicio_promo AND pe.fin_promo and date(now()) between pe.inicio_alojamiento and pe.fin_alojamiento AND ( FIND_IN_SET('A',pe.tipo)) group by pe.id_promocion order by pr.valor_promocion desc";
MySqlCommand cmd13 = new MySqlCommand(tipo_promo, con);
MySqlDataAdapter da13 = new MySqlDataAdapter(cmd13);
da13.Fill(tipo);
return tipo;
}
tipo_promonic
-------------
porcentaje
porcentaje
fixed
discount
porcentaje
discount
discount
fixed
fixed
porcentaje
porcentaje
the above result like above table table ok now i am trying to check in "tipo_promonic" column contains some rows so i am checking if "tipo_promonic" column contains porcentaje,fixed,discount then go to some function else it goto another function ok but in "tipo_promonic" column contains many duplicate values so how to check the condition. please help me out from this problem.

Try Re-framing your SQL query using DISTINCT keyword to avoid Duplicate record
string tipo_promo = "select DISTINCT pr.tipo_promocion from promocion_edificio pe inner ..."
Try using DataReader
MySqlConnection con = new MySqlConnection(connectionstring);
string tipo_promo = "select DISTINCT pr.tipo_promocion from promocion_edificio pe inner.."
MySqlCommand cmd13 = new MySqlCommand(tipo_promo, con);
DataReader dr = cmd13.ExecuteReader();
while(dr.Read())
{
if(dr[0].ToString() == "YourOption")
{//Do this;}
}

This is for a data table. You can make out for DataAdapter or Dataset according to your need. This is basically a loop which checks each row for a value of a particular column.
foreach (DataRow dr in dataTable.Rows)
{
if (dr["typo_promonic"].Equals("porcentaje"))
{
//your code here.
}
else if (dr["tipo_promonic"].Equals("discount"))
{
//your code here.
}
else
{
//your code here.
}
}
You can add more else...if as per your options. Whatever you want to do, you can do in those code blocks.

SQL SELECT & multiple AND query statement in visual c# [closed]

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In this query statement i want sum of the number of days in the 'datetime' column where emp_ID equals to selected emp_ID in the textBox2 'and' leavetype = Fullday 'and' status = approved. this is my code
string selectSql =
"Select sum(datetime)
From Lea_information
Where emp_ID= ('" + textBox2.Text + "')
and (leave_type,status) = values (Fullday,Approved)";

Try like this
string selectSql =
"Select sum(datetime)
From Lea_information
Where emp_ID= '" + textBox2.Text + "'
AND leave_type ='Fullday'
AND status = 'Approved'";

Use
ing selectSql = "Select sum(datetime) from Lea_information where emp_ID= ('" + textBox2.Text + "') and leave_type = FullDay and status = Approved)";
Not sure which database you are using, but I've never seen statements like you have written there before.

Select First table data and pass it to int value and print it in second table? ERRORS [closed]

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I want to select id from one table and insert that id to another table.
First I need to read my first table id and want to pass it to string.
Then I need to pass that string to second table.
String selQuery = "SELECT Id FROM MapDataImage WHERE Source='" + TextBox1.Text + "';";
{
int MId = int.TryParse(Id);
String QueryStr = "INSERT INTO User_Images VALUES (#Image)";
SqlCommand scmd = new SqlCommand(QueryStr, conn);
SqlDataReader sqldread = scmd.ExecuteReader();
//String QueryStr = "UPDATE MapDataImage SET Image = #Image WHERE Source='" + TextBox1.Text + "';";
//SqlCommand scmd = new SqlCommand(QueryStr, conn);
scmd.Parameters.Add("#Image", SqlDbType.VarBinary).Value = imgbytes;
scmd.ExecuteNonQuery();
}
so is this correct?
int MId = int.TryParse(Id); //the name id does not exist in current context?
but i want to retrieve particular id value from database
or
int MId = int.TryParse(#Id);

int MId = int.Parse("Id");
Will never work. "Id" is a string literal, it can never be an integer. I think you need to specify a variable
int mId = int.Parse(id);
Aside that, try using TryParse so it's safer.
Also use paramerterised queries on your SELECT statement to prevent SQL Injection.
Please post the rest of your code and I will adjust my answer to accomodate.

You don't create DataReaders objects by yourself. Instead you obtain a reference to DataReader object by invoking ExecuteReader method of Command class.
http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqlcommand.executereader.aspx