I need to insert into a table "pass" or "fail", if from the query done there is a single fail instead of 'RProva' I have to put "fail" if the query can't find a single fail instead of 'RProva' I have to insert "pass", the query is working but I can't figure out how to do the if with the results of a query, maybe I have to use a "for"? Don't know. It is the attempt to make it, the second is the query where I have to insert the result of the possbile "IF"
1.
SqlCommand cmdRD = new SqlCommand("SELECT ResItem AS RD FROM tSE JOIN tL ON tSE.idSE=tL.idL WHERE tL.Selection=1");
var RD = cmdRD.ExecuteScalar();
var values = new List<string>();
using (cmdRD,sqliteCon)
{
using (SqlDataReader reader = cmdRD.ExecuteReader())
{
while (reader.Read())
{
values.Add(reader[0].ToString());
}
}
}
2.
SqlCommand cmd1 = new SqlCommand("INSERT INTO tSD(NomeItem,ResItemDet,DateStartDet,DateEndDet) OUTPUT inserted.Id VALUES (#NI,#RProva,#DATESE,#DATEED)");
cmd1.Parameters.AddWithValue("#DATESE", DATESE);
cmd1.Parameters.AddWithValue("#DATEED", DATEED);
cmd1.Parameters.AddWithValue("#NI", NI);
using (cmd1,sqliteCon)
{
foreach (var value in values)
{
if (value.Equals(pass))
{
cmd1.Parameters.AddWithValue("#RProva", value);
}
else
{
cmd1.Parameters.AddWithValue("#RProva", fail);
}
cmd1.ExecuteNonQuery();
}
}
int generatedId = Convert.ToInt32(cmd1.ExecuteScalar());
cmd1.Parameters.Clear();
SqlCommand cmd2 = new SqlCommand("UPDATE tSE SET FK_TSD_id = #tsdId FROM tL JOIN tSE ON tL.idL = tSE.idSE WHERE tL.Selection=1 ", sqliteCon);
cmd2.Parameters.AddWithValue("#tsdId", generatedId);
cmd2.ExecuteNonQuery();
MessageBox.Show("Dato Aggiunto");
}
sqliteCon.Close();
1.1
SqlCommand cmdRD = new SqlCommand("SELECT ResItem AS RD FROM tSE JOIN tL ON tSE.idSE=tL.idL WHERE tL.Selection=1", sqliteCon);
var RD = cmdRD.ExecuteScalar();
var tot =pass;
using (cmdRD)
{
using (SqlDataReader reader = cmdRD.ExecuteReader())
{
while (reader.Read())
{
if(reader[0].ToString()==fail)
{
tot = fail;
break;
}
}
MessageBox.Show(tot);
}
}
i'm arrived to that(1.1) it works but i've to insert the TOT into RProva
Based on your question and comment I think you misunderstood ExecuteScalar:
ExecuteScalar executes the query, and returns the first column of the first row in the result set returned by the query. learn.microsoft.com/en-us/dotnet/api/system.data.sqlclient.sqlcommand.executescalar
I dont know the Type of "RD" or "PASS", but the IF in your example (when using ExecuteScalar) seems OK. Else when you are using ExecuteReader you should use some kind of an loop to iterate through the Items. Like this:
string pass = "abc"; // guessing types and values
string fail = "failed";
string sqliteCon = "Data Source=(localdb)\\MSSQLLocalDB;Database=BooksDb";
using (SqlConnection connection = new SqlConnection(sqliteCon))
{
connection.Open();
var queryString = #"SELECT ResItem AS RD
FROM tSE
JOIN tL ON tSE.idSE = tL.idL
WHERE tL.Selection=1";
var values = new List<string>();
using (SqlCommand command = new SqlCommand(queryString, connection))
{
using (SqlDataReader reader = command.ExecuteReader())
{
while (reader.Read())
{
values.Add(reader[0].ToString());
}
}
}
var queryInsert = #"INSERT INTO tSD (NomeItem,ResItemDet,DateStartDet,DateEndDet)
VALUES (#NI, #RProva, #DATESE, #DATEED)";
using (SqlCommand command2 = new SqlCommand(queryInsert, connection))
{
foreach(var value in values)
{
command2.Parameters.Clear();
if (value.Equals(pass))
{
command2.Parameters.AddWithValue("#RProva", value);
}
else
{
command2.Parameters.AddWithValue("#RProva", fail);
}
command2.ExecuteNonQuery();
}
}
}
Theres for sure a better way, but maybe this helps you out.
EDIT:
Here is how I would implement your code example:
using (SqlConnection sqliteCon = new SqlConnection(connection))
{
sqliteCon.Open();
var values = new List<string>();
var query = "SELECT ResItem AS RD FROM tSE JOIN tL ON tSE.idSE=tL.idL WHERE tL.Selection=1";
using (SqlCommand cmdRD = new SqlCommand(query, sqliteCon))
{
var RD = cmdRD.ExecuteScalar();
using (SqlDataReader reader = cmdRD.ExecuteReader())
{
while (reader.Read())
{
values.Add(reader[0].ToString());
}
}
}
int generatedId = 0;
var query2 = "INSERT INTO tSD(NomeItem,ResItemDet,DateStartDet,DateEndDet) OUTPUT inserted.Id VALUES (#NI,#RProva,#DATESE,#DATEED)";
using (SqlCommand cmd1 = new SqlCommand(query2, sqliteCon))
{
foreach (var value in values)
{
cmd1.Parameters.Clear();
cmd1.Parameters.AddWithValue("#DATESE", DATESE);
cmd1.Parameters.AddWithValue("#DATEED", DATEED);
cmd1.Parameters.AddWithValue("#NI", NI);
if (value.Equals(pass))
{
cmd1.Parameters.AddWithValue("#RProva", value);
}
else
{
cmd1.Parameters.AddWithValue("#RProva", fail);
}
cmd1.ExecuteNonQuery();
}
generatedId = Convert.ToInt32(cmd1.ExecuteScalar());
}
var query3 = "UPDATE tSE SET FK_TSD_id = #tsdId FROM tL JOIN tSE ON tL.idL = tSE.idSE WHERE tL.Selection=1 ";
using (SqlCommand cmd2 = new SqlCommand(query3, sqliteCon))
{
cmd2.Parameters.AddWithValue("#tsdId", generatedId);
cmd2.ExecuteNonQuery();
}
}
Related
I want to concatenate the query result in c#. Below is the resulting image
In my code, I have done
using (MySqlConnection cn = new MySqlConnection(conn.ConnectionString))
{
string query = "SELECT m.`read_param` FROM mdc_request m WHERE m.`row_id` = #row_id";
cn.Open();
MySqlCommand cmd = new MySqlCommand(query, cn);
cmd.CommandText = query;
cmd.Parameters.AddWithValue("#row_id", iterations.row_id);
reader = cmd.ExecuteReader();
while (reader.Read())
{
// here I want to save the result in one single variable
}
}
Update 1
As per #Rahul answer, I have done the following
public async Task YtlbusMethod(List<Iterations> ytlbus)
{
MySqlConnection cn = null;
int limitRequest = 10;
for (int i = 10; i > 0; i--)
{
foreach (var item in ytlbus)
{
using (cn = new MySqlConnection(conn.ConnectionString))
{
string query = "SELECT m.`time` FROM `mdc_meter_config` m WHERE m.`row_id` = #row_id";
cn.Open();
MySqlCommand cmd = new MySqlCommand(query, cn);
cmd.CommandText = query;
cmd.Parameters.AddWithValue("#row_id", item.row_id);
reader = cmd.ExecuteReader();
while (reader.Read())
{
string time = (string)reader["time"];
if(item.time == time)
{
int sleeptime = Convert.ToInt32(item.time);
sleeptime = sleeptime * 1000;
Thread.Sleep(sleeptime);
Task.Factory.StartNew(() => PortHitmethod(item));
}
}
}
cn.Close();
// select query kerni hy ..jis main wohi data ay jo tu yahan pass ker raha hy... where k ander just tuny row id pass kerni hy.
//if(item.time== query main jo time aya hy woh)
//{
//}
}
}
}
public async Task PortHitmethod(Iterations iterations)
{
MySqlConnection cn = null;
List<string> data = new List<string>();
using (cn = new MySqlConnection(conn.ConnectionString))
{
string query = "SELECT m.`read_param` FROM mdc_request m WHERE m.`row_id` = #row_id";
cn.Open();
MySqlCommand cmd = new MySqlCommand(query, cn);
cmd.CommandText = query;
cmd.Parameters.AddWithValue("#row_id", iterations.row_id);
reader = cmd.ExecuteReader();
while (reader.Read())
{
data.Add(reader["read_param"].ToString());
}
}
cn.Close();
var single = string.Join("", data);
}
Now the issue that I am facing is that I am unable to get all the rows data. The total rows are 9 but I am getting less than that
How can I achieve this? Any help would be highly appreciated.
Looks like those are integer value then you can do something like
List<int> data = new List<int>;
while (reader.Read())
{
data.Add(int.Parse(reader["read_param"].ToString()));
}
Then you can use string.Join() method like
var single = string.Join(",", data);
Based on #Rahul, your code should be:
Your update 1 is different code.
What do you want to achieve here.
List<string> data = new List<string>();
using (MySqlConnection cn = new MySqlConnection(conn.ConnectionString))
{
string query = "SELECT m.`read_param` FROM mdc_request m WHERE m.`row_id` = #row_id";
cn.Open();
MySqlCommand cmd = new MySqlCommand(query, cn);
cmd.CommandText = query;
cmd.Parameters.AddWithValue("#row_id", iterations.row_id);
reader = cmd.ExecuteReader();
while (reader.Read())
{
data.Add(reader["read_param"].ToString());
}
}
var single = string.Join("", data);
I am having the below code where I am querying the MySQL database. I need to replace my select query to prepare statement
public static void ValidateName(List<Employees> EmpList, string Grp)
{
var connStr = ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString;
string selectQuery;
for (int i = 0; i < EmpList.Count; i++)
{
selectQuery = "Select EmpName from Employee where group = #Grp AND #Name in (FirstName, LastName);";
using (MySqlConnection conn = new MySqlConnection(connStr))
using (MySqlCommand cmd = new MySqlCommand(selectQuery, conn))
{
cmd.Parameters.Add("#Grp", MySqlDbType.VarChar).Value = Grp;
cmd.Parameters.Add("#Name", MySqlDbType.VarChar).Value = EmpList[i].Name;
conn.Open();
var reader = cmd.ExecuteReader();
List<string> lineList = new List<string>();
while (reader.Read())
{
lineList.Add(reader.GetString(0));
}
if (lineList.Count <=0)
{
WriteValidationFailure(EmpList[i], "Name doesnot exists in the DB");
}
conn.Close();
}
}
}
This code works perfectly. But for improvement I need to use the prepare statements instead of the query I am using. Because I am having similar kinds of various validation in my code, I am not sure how to reuse the parameters effectively.
You are very close. Just call cmd.Prepare(), keep references to the parameters, and reuse the command:
public static void ValidateName(List<Employees> EmpList, string Grp)
{
var connStr = ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString;
string selectQuery;
selectQuery = "Select EmpName from Employee where group = #Grp AND #Name in (FirstName, LastName);";
using (MySqlConnection conn = new MySqlConnection(connStr)) {
conn.Open();
using (MySqlCommand cmd = new MySqlCommand(selectQuery, conn))
{
var prmGrp = cmd.Parameters.Add("#Grp", MySqlDbType.VarChar);
var prmName = cmd.Parameters.Add("#Name", MySqlDbType.VarChar);
cmd.Prepare();
for (int i = 0; i < EmpList.Count; i++)
{
prmGrp.Value = Grp;
prmName.Value = EmpList[i].Name;
using (var reader = cmd.ExecuteReader()) {
List<string> lineList = new List<string>();
while (reader.Read())
{
lineList.Add(reader.GetString(0));
}
if (lineList.Count <=0)
{
WriteValidationFailure(EmpList[i], "Name doesnot exists in the DB");
}
}
}
}
conn.Close();
}
}
I need to know how to get all the clientID that are #2 so i could get the programs they are assigned to...so far my code only gets the first clientID with #2 in it...
int progs;
string Command = #"select * from clientprogram where clientProgClientID = #clientID;";
using (MySqlConnection mConnection = new MySqlConnection(mycon))
{
mConnection.Open();
using (MySqlCommand cmd2 = new MySqlCommand(Command, mConnection))
{
cmd2.Parameters.Add(new MySqlParameter("#clientID", lblcID.Text));
using (MySqlDataReader reader = cmd2.ExecuteReader())
{
if (reader.Read())
{
progs = (int)reader["clientProgramID"];
cmbProgram.Items.Add(progs);
}
}
}
mConnection.Close();
}
Change
if (reader.Read())
to
while (reader.Read())
It seems it should be in a loop to add records recursively rather than just the first one
of course it only get the first result because you are reading it only once.
use while(reader.Read()) instead of if(reader.Read()).
while(reader.Read())
{
progs = (int)reader["clientProgramID"];
cmbProgram.Items.Add(progs);
}
change
if (reader.Read())
to
while(reader.Read())
side note; don't use select * when you only need single column data, use select Coumnname from yourtable
int progs;
string Command = #"select * from clientprogram where clientProgClientID = #clientID;";
using (MySqlConnection mConnection = new MySqlConnection(mycon))
{
mConnection.Open();
using (MySqlCommand cmd2 = new MySqlCommand(Command, mConnection))
{
cmd2.Parameters.Add(new MySqlParameter("#clientID", lblcID.Text));
using (MySqlDataReader reader = cmd2.ExecuteReader())
{
while (reader.Read()) // CHANGE TO THIS
{
progs = (int)reader["clientProgramID"];
cmbProgram.Items.Add(progs);
}
}
}
mConnection.Close();
}
I have a constructor that takes data from a SQL Server database and puts it in a local SQLite database:
public ForemanController()
{
connectionString.DataSource = "dxdb02v";
connectionString.InitialCatalog = "QTRAX4619410";
connectionString.UserID = "tunnelld";
connectionString.Password = "david";
string queryString = "SELECT * FROM [QTRAXAdmin].[vwQT_Foreman]";
List<Foreman> list;
// Creates a SQL connection
using (var connection = new SqlConnection(connectionString.ToString()))
{
using (var command = new SqlCommand(queryString, connection))
{
connection.Open();
using (var reader = command.ExecuteReader())
{
list = new List<Foreman>();
while (reader.Read())
{
list.Add(new Foreman { ForeBadge = reader.GetString(0), ForeName = reader.GetString(1) });
}
}
}
connection.Close();
allForeman = list.ToArray();
}
string deleteSQL = "DELETE FROM Foreman;";
using (SQLiteConnection SQLconn1 = new SQLiteConnection(SQLiteConnectionString))
{
using (var command = new SQLiteCommand(deleteSQL, SQLconn1))
{
command.Connection.Open();
command.ExecuteNonQuery();
}
}
using (SQLiteConnection SQLconn2 = new SQLiteConnection(SQLiteConnectionString))
{
SQLiteCommand cmd2 = SQLconn2.CreateCommand();
foreach (Foreman row in allForeman)
{
cmd2.CommandText = "INSERT INTO Foreman (ForeBadge, ForeName) VALUES (#param1, #param2);";
cmd2.Parameters.Add(new SQLiteParameter("#param1", row.ForeBadge));
cmd2.Parameters.Add(new SQLiteParameter("#param2", row.ForeName));
cmd2.ExecuteNonQuery();
}
}
}
Everything seems to be working fine until the last using statement:
using (SQLiteConnection SQLconn2 = new SQLiteConnection(SQLiteConnectionString))
{
SQLiteCommand cmd2 = SQLconn2.CreateCommand();
foreach (Foreman row in allForeman)
{
cmd2.CommandText = "INSERT INTO Foreman (ForeBadge, ForeName) VALUES (#param1, #param2);";
cmd2.Parameters.Add(new SQLiteParameter("#param1", row.ForeBadge));
cmd2.Parameters.Add(new SQLiteParameter("#param2", row.ForeName));
cmd2.ExecuteNonQuery();
}
}
I'm getting this error:
That's because that's the only place you forgot to open the connection.
add this: SQLconn2.Open();
You forgot to open the connection.
SQLConn2.Open();
If I have a DbCommand defined to execute something like:
SELECT Column1 FROM Table1
What is the best way to generate a List<String> of the returned records?
No Linq etc. as I am using VS2005.
I think this is what you're looking for.
List<String> columnData = new List<String>();
using(SqlConnection connection = new SqlConnection("conn_string"))
{
connection.Open();
string query = "SELECT Column1 FROM Table1";
using(SqlCommand command = new SqlCommand(query, connection))
{
using (SqlDataReader reader = command.ExecuteReader())
{
while (reader.Read())
{
columnData.Add(reader.GetString(0));
}
}
}
}
Not tested, but this should work fine.
Loop through the Items and Add to the Collection. You can use the Add method
List<string>items=new List<string>();
using (var con= new SqlConnection("yourConnectionStringHere")
{
string qry="SELECT Column1 FROM Table1";
var cmd= new SqlCommand(qry, con);
cmd.CommandType = CommandType.Text;
con.Open();
using (SqlDataReader objReader = cmd.ExecuteReader())
{
if (objReader.HasRows)
{
while (objReader.Read())
{
//I would also check for DB.Null here before reading the value.
string item= objReader.GetString(objReader.GetOrdinal("Column1"));
items.Add(item);
}
}
}
}
Or a nested List (okay, the OP was for a single column and this is for multiple columns..):
//Base list is a list of fields, ie a data record
//Enclosing list is then a list of those records, ie the Result set
List<List<String>> ResultSet = new List<List<String>>();
using (SqlConnection connection =
new SqlConnection(connectionString))
{
// Create the Command and Parameter objects.
SqlCommand command = new SqlCommand(qString, connection);
// Create and execute the DataReader..
connection.Open();
SqlDataReader reader = command.ExecuteReader();
while (reader.Read())
{
var rec = new List<string>();
for (int i = 0; i <= reader.FieldCount-1; i++) //The mathematical formula for reading the next fields must be <=
{
rec.Add(reader.GetString(i));
}
ResultSet.Add(rec);
}
}
If you would like to query all columns
List<Users> list_users = new List<Users>();
MySqlConnection cn = new MySqlConnection("connection");
MySqlCommand cm = new MySqlCommand("select * from users",cn);
try
{
cn.Open();
MySqlDataReader dr = cm.ExecuteReader();
while (dr.Read())
{
list_users.Add(new Users(dr));
}
}
catch { /* error */ }
finally { cn.Close(); }
The User's constructor would do all the "dr.GetString(i)"
Where the data returned is a string; you could cast to a different data type:
(from DataRow row in dataTable.Rows select row["columnName"].ToString()).ToList();
This version has the same purpose of #Dave Martin but it's cleaner, getting all column, and easy to manipulate the data if you wan't to put it on Email, View, etc.
List<string> ResultSet = new List<string>();
using (SqlConnection connection = DBUtils.GetDBConnection())
{
connection.Open();
string query = "SELECT * FROM DATABASE";
using (SqlCommand command = new SqlCommand(query, connection))
{
using (SqlDataReader reader = command.ExecuteReader())
{
while (reader.Read())
{
var rec = new List<string>();
for (int i = 0; i <= reader.FieldCount - 1; i++)
{
rec.Add(reader.GetString(i));
}
string combined = string.Join("|", rec);
ResultSet.Add(combined);
}
}
}
}