How can i get Total records count in query result
SqlConnection con1 = new SqlConnection(ConfigurationManager.ConnectionStrings["con1"].ConnectionString);
string sql = "select Fare , OrderAmount FROM orderitems OI INNER JOIN Orders O ON O.OrderID = OI.OrderID WHERE PaymentStatusID = 1 AND o.orderid ="+Orderid;
SqlCommand comd = new SqlCommand(sql, con1);
con1.Open();
comd.ExecuteNonQuery();
Above is my sql query i need result count, can some one help me
Thanks in advance.
ExecuteNonQuery is used for query like insert/update/delete.
Use ExecuteScalar instead:
string sql = "select count(*) FROM orderitems OI INNER JOIN Orders O ON O.OrderID = OI.OrderID WHERE PaymentStatusID = 1 AND o.orderid ="+Orderid;
SqlCommand comd = new SqlCommand(sql, con1);
con1.Open();
int count = Convert.ToInt32(comd.ExecuteScalar());
If you don't need the Fare and the OrderAmount (a bit strange, since the sql script you have written contains them), you could replace them with a COUNT(*).
string sql = "select COUNT(*) FROM orderitems OI INNER JOIN Orders O ON O.OrderID = OI.OrderID WHERE PaymentStatusID = 1 AND o.orderid ="+Orderid;
Then you can read this fairly easily, like below:
int numberOfRecords = Convert.ToInt32(comd.ExecuteScalar());
On the other hand, if you need them, you could count the number of records in the sql reader you will use to read those results, like below:
SqlDataReader sqlReader = comd.ExecuteReader();
int numberOfRecords = 0;
while(sqlReader.Read())
{
// do things
numberOfRecords++;
}
Note
In any case, you can't use the ExecuteNonQuery method, since you want to read something from a database. You don't want to create, update or delete something. Only in the latter cases we use this method.
One more important note is about the security of the queries you build and then execute is to avoid string concatenation for passing the values of parameters. This makes your app vulnerable to sql injections, one of the major ways of attacks. Instead of doing this, you could use a sql parametrized query, like below:
string sql = "select Fare , OrderAmount FROM orderitems OI INNER JOIN Orders O ON O.OrderID = OI.OrderID WHERE PaymentStatusID = 1 AND o.orderid=#Orderid";
SqlCommand cmd = new SqlCommand(sql, con1);
cmd.Parameters.Add("#Orderid",OrderId);
Related
I'm new to linq and trying to understand it. I'm trying to fill a data table through linq but getting an error in the sql command adapter.
Below is the code which I'm using, don't know if I'm using it the right way!
This is the error I'm getting:
Error 7 Cannot implicitly convert type
'System.Linq.IQueryable' to
MySql.Data.MySqlClient.MySqlCommand'
{
northwindEntities1 nw = new northwindEntities1();
var query = from c in nw.customers
join o in nw.orders on c.CustomerID equals o.CustomerID // first join
join od in nw.orderdetails on o.OrderID equals od.OrderID // second join
join p in nw.products on od.ProductID equals p.ProductID // third join
where c.ContactName.StartsWith("Maria Anders")
select new {
o.CustomerID,
c.ContactName,
o.OrderID,
p.ProductID,
p.ProductName,
od.Quantity,
p.UnitPrice
};
MySqlDataAdapter da = new MySqlDataAdapter();
da.SelectCommand = query;
DataTable datatable = new DataTable();
da.Fill(datatable); // getting value according to imageID and fill dataset
ReportDocument crystalReport = new ReportDocument(); // creating object of crystal report
crystalReport.Load(Server.MapPath("~/custreport.rpt")); // path of report
crystalReport.SetDataSource(datatable); // binding datatable
CrystalReportViewer1.ReportSource = crystalReport;
crystalReport.ExportToHttpResponse
(CrystalDecisions.Shared.ExportFormatType.PortableDocFormat, Response, true, "PersonDetails");
}
A SQL query is not the same as a LINQ query, they are totally different.
LINQ by itself is a set of query language features that used are to query different data sources, but it is not the same as a SQL query. You have miss understand that. So you can't pass it to act like SQL query.
You can't pass System.Linq.IQueryable which coming from the variable linq to the MysqLCommand CommandText Property, you should pass a string which should be the MysQL query not LinQ query. Something like this:
string query = "Select * FROM Customers INNER JOIN ..."; //you have to pass sql query
MySqlDataAdapter da = new MySqlDataAdapter();
da.SelectCommand = query;
...
I'm making an ASP.Net web application, but it is returning a syntax error whenever I try to load the page.
My DB schema can be seen here http://sqlfiddle.com/#!2/739c4/7
Here is the SQL query:
SELECT
tblOrderTransactions.ordertransaction_orderid AS orderid,
tblProducts.product_name AS productname,
tblOrders.order_customer AS ordercustomer
FROM
tblProducts
LEFT JOIN tblOrderTransactions
ON tblProducts.product_id = tblOrderTransactions.ordertransaction_productid
LEFT JOIN tblOrders
ON tblOrderTransactions.ordertransaction_orderid = tblOrders.order_id
WHERE
(
(
(
tblOrderTransactions.ordertransaction_orderid
)
=3
)
) and (
(
(tblOrders.order_customer)
=3
)
)
The SQL works in sqlfiddle, and if I remove the part that says
LEFT JOIN tblOrders
ON tblOrderTransactions.ordertransaction_orderid = tblOrders.order_id
in my web application, the table loads. Adding this second INNER JOIN seems to be messing it up, but the same query works in sqlfiddle, so I believe the SQL is correct.
The error message I receive is
Syntax error (missing operator) in query expression 'tblProducts.product_id = tblOrderTransactions.ordertransaction_productid LEFT JOIN tblOrders ON tblOrderTransactions.ordertransaction_orderid = tblOrders.order_i'.
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 (missing operator) in query expression 'tblProducts.product_id = tblOrderTransactions.ordertransaction_productid LEFT JOIN tblOrders ON tblOrderTransactions.ordertransaction_orderid = tblOrders.order_i'.
C# Code inside the application:
string orderID = Request.QueryString["id"];
OleDbConnection conn = new OleDbConnection();
conn.ConnectionString = ConfigurationManager.ConnectionStrings["finalConnString"].ConnectionString;
string commText = #"SELECT tblOrderTransactions.ordertransaction_orderid AS orderid, tblProducts.product_name AS productname
FROM tblProducts
LEFT JOIN tblOrderTransactions
ON tblProducts.product_id = tblOrderTransactions.ordertransaction_productid
LEFT JOIN tblOrders
ON tblOrderTransactions.ordertransaction_orderid = tblOrders.order_id
WHERE (((tblOrderTransactions.ordertransaction_orderid)=?)) ";
conn.Open();
OleDbCommand comm = conn.CreateCommand();
comm.Connection = conn;
comm.CommandText = commText;
OleDbParameter param;
param = comm.CreateParameter();
param.DbType = DbType.Int32;
param.Direction = ParameterDirection.Input;
param.Value = Int32.Parse(orderID);
comm.Parameters.Add(param);
//param = comm.CreateParameter();
//param.DbType = DbType.Int32;
//param.Direction = ParameterDirection.Input;
//param.Value = Session["LoggedInId"];
//comm.Parameters.Add(param);
OleDbDataReader reader = comm.ExecuteReader();
if (reader.HasRows)
{
rptOrders.DataSource = reader;
rptOrders.DataBind();
lblOrderNumber.Text = orderID.ToString();
}
else
{
Response.Write("You are not authorized to view this order.");
}
//Free up the connection
conn.Close();
The SQL Statement must have the joins nested in parentheses because of Access specific syntax (Thank you #MattiVirkkunen for that knowledge).
The correct way to write this SQL statement is:
SELECT tblOrderTransactions.ordertransaction_orderid, tblProducts.product_name, tblOrders.order_customer
FROM tblProducts
INNER JOIN (tblOrders
INNER JOIN tblOrderTransactions
ON tblOrders.[order_id] = tblOrderTransactions.[ordertransaction_orderid])
ON tblProducts.[product_id] = tblOrderTransactions.[ordertransaction_productid]
WHERE (((tblOrderTransactions.ordertransaction_orderid)=3)) and (((tblOrders.order_customer)=3))
First, I would suggest working with aliases to keep your query a little shorter to read (and type) such as below.
SELECT
OT.ordertransaction_orderid AS orderid,
P.product_name AS productname,
O.order_customer AS ordercustomer
FROM
tblProducts P
LEFT JOIN tblOrderTransactions OT
ON P.product_id = OT.ordertransaction_productid
LEFT JOIN tblOrders
ON OT.ordertransaction_orderid = O.order_id
WHERE
OT.ordertransaction_orderid = 3
and O.order_customer = 3
Second, it does look completely legit and nothing glaring out as invalid. But error of loading the page MIGHT be due to no records being returned. You have your query with left-joins, but then throwing in your WHERE clause for both the "tblOrderTransactions" and "tblOrders" tables changes it to an INNER JOIN result.
So, your query looking for order ID = 3 and also the customer = 3, what if that was not the case, that order #3 was customer #1 which would result in NO RECORDS.
Getting back to now seeing your posted syntax, it looks unbalanced parens ((( )) that might be the issue.
And a final review.. Your "ID" from the query string. Is it properly doing an int.Parse() against it? I know on some instances of int.parse() I've done in the past, if the string started with a space vs actual number, int.Parse() would throw an error... Confirm the incoming values and did it really convert as you expected.
It's a pretty simple problem, but I can't find a solution (not even sure what question to google here).
Here is my code to create the command:
var targetStartDate = "October 2014";//ConfigurationManager.AppSettings["StartDateString"].ToString(CultureInfo.InvariantCulture);
var acceptedStatusCodes = 4;//ConfigurationManager.AppSettings["ImportStatusIds"].ToString(CultureInfo.InvariantCulture);
using (var connection = new SqlConnection(connString))
{
using (var cmd = connection.CreateCommand())
{
cmd.CommandText = #"
SELECT
ai.FirstName,
ai.LastName,
ai.Email,
ai.SSN,
ai.Phone,
ai.Program,
r.FirstName + ' ' + r.LastName AS RepName,
d.Name AS StartDateName,
s.CvId AS CvSySchoolStatusId,
ai.CampusId as SyStudentId
FROM
dbo.aspnet_Users AS u LEFT OUTER JOIN
dbo.ApplicantInfo AS ai ON u.UserId = ai.UserId LEFT OUTER JOIN
dbo.AdmissionReps AS r ON ai.AdmissionsRepId = r.RepId LEFT OUTER JOIN
dbo.ProgramStartDate AS d ON ai.StartDateId = d.CvStartDateId LEFT OUTER JOIN
dbo.CvSySchoolStatus AS s ON ai.CvSySchoolStatusId = s.CvId
where d.Name = '#StartDate'
and CvSySchoolStatusId in (#Statuses)";
cmd.Parameters.AddWithValue("#StartDate", SqlDbType.VarChar).Value = (object) targetStartDate;
cmd.Parameters.AddWithValue("#Statuses", SqlDbType.Int).Value = (object) acceptedStatusCodes;
...
}
....
}
The reader sends the command fine, I can see it go through via SQL profiler:
exec sp_executesql N'
SELECT
ai.FirstName,
ai.LastName,
ai.Email,
ai.SSN,
ai.Phone,
ai.Program,
r.FirstName + '' '' + r.LastName AS RepName,
d.Name AS StartDateName,
s.CvId AS CvSySchoolStatusId,
ai.CampusId as SyStudentId
FROM
dbo.aspnet_Users AS u LEFT OUTER JOIN
dbo.ApplicantInfo AS ai ON u.UserId = ai.UserId LEFT OUTER JOIN
dbo.AdmissionReps AS r ON ai.AdmissionsRepId = r.RepId LEFT OUTER JOIN
dbo.ProgramStartDate AS d ON ai.StartDateId = d.CvStartDateId LEFT OUTER JOIN
dbo.CvSySchoolStatus AS s ON ai.CvSySchoolStatusId = s.CvId
where d.Name = ''#StartDate''
and CvSySchoolStatusId in (#Statuses)'
,N'#StartDate nvarchar(12),#Statuses int'
,#StartDate=N'October 2014'
,#Statuses=4
This query gives me 0 results, but if I take this exact query and just paste in the parameters and run just the query text, I get the expected results. Any idea where I am going wrong here?
You need to remove single quotes around your parameter in string query
this:
where d.Name = '#StartDate'
should be:
where d.Name = #StartDate
No single parameters.
Perhaps it's the extra single quotes around startdate. I think you might want to remove those single quotes and try again. Should look like:
...
where d.Name = #StartDate
I have a problem with query in C#.
I have this part of code :
string query1 = #"
SELECT TOP #howManyRows * FROM
(
SELECT
PRODUCTCODE_.ID_ AS PRODUCTCODE_ID_,
PRODUCTCODE_.CATEGORY_ AS CATEGORY_,
PRODUCTCODE_.DESCRIPTION_ AS DESCRIPTION_,
PRODUCTCODE_.MANUFACTURER_ AS MANUFACTURER_,
PRODUCTLINE_.CREATION_DATE_ AS CREATION_DATE_,
ROW_NUMBER() OVER (ORDER BY PRODUCTCODE_.CATEGORY_) AS ROWNUMBER_,
TOTALROWS_ = COUNT(*) OVER()
FROM
PRODUCTCODE_
INNER JOIN
PRODUCTLINE_ ON PRODUCTLINE_.ID_ = PRODUCTCODE_.PRODUCTLINE_ID_
) _tmpList
WHERE
ROWNUMBER_ >= #startingWith
ORDER BY CATEGORY_
";
SqlParameter param1 = new SqlParameter();
param1.ParameterName = "#howManyRows";
param1.Value = resultPerPage; //`resultPerPage` is an integer function parameter
SqlParameter param2 = new SqlParameter();
param2.ParameterName = "#startingWith";
param2.Value = startsWith; //`startWith` is an integer function parameter
SqlCommand cmd = new SqlCommand( query1, connect );
cmd.Parameters.Add( param1 );
cmd.Parameters.Add( param2 );
When debug arrived to SqlDataReader reader = cmd.ExecuteReader(); then the exception is thrown:
Incorrect syntax near #howManyRows ...
Why ? I defined and added howManyRows with Parameters property.
Where is my mistakes ?
Change your top query syntax from
SELECT TOP #howManyRows * FROM
to
SELECT TOP (#howManyRows) * FROM
Try wrapping the parameter specified next to TOP in parentheses, like so:
SELECT TOP (#howManyRows) * FROM
You need parenthesis to parametrise TOP
SELECT TOP (#howManyRows) * FROM
This will work.
SELECT
PRODUCTCODE_.ID_ AS PRODUCTCODE_ID_,
PRODUCTCODE_.CATEGORY_ AS CATEGORY_,
PRODUCTCODE_.DESCRIPTION_ AS DESCRIPTION_,
PRODUCTCODE_.MANUFACTURER_ AS MANUFACTURER_,
PRODUCTLINE_.CREATION_DATE_ AS CREATION_DATE_,
ROW_NUMBER() OVER (ORDER BY PRODUCTCODE_.CATEGORY_) AS ROWNUMBER_,
TOTALROWS_ = COUNT(*) OVER()
FROM
PRODUCTCODE_
INNER JOIN
PRODUCTLINE_ ON PRODUCTLINE_.ID_ = PRODUCTCODE_.PRODUCTLINE_ID_
) _tmpList
WHERE
ROWNUMBER_ between #startingWith and (#startingWith + #howManyRows)
ORDER BY CATEGORY_
You need to add a couple of parenthesis to make it work.
SELECT TOP (#howManyRows) * FROM
Use SELECT TOP(#howManyRows) syntax
You can do
SELECT TOP (#howManyRows) * FROM
But this really depends on the Database Server you are using. For example, this is only supported from MSSQL Server 2005 upwards
If this does not work you can do the following...
You can include this into your query string. But this can result in Sql Injection if you don't check the value of your variable.
Sample
int top = 10;
Int32.TryParse(howManyRows.ToString(), out top);
string query1 = "SELECT TOP " + top.ToString() + #" * FROM
(
SELECT
PRODUCTCODE_.ID_ AS PRODUCTCODE_ID_,
PRODUCTCODE_.CATEGORY_ AS CATEGORY_,
PRODUCTCODE_.DESCRIPTION_ AS DESCRIPTION_,
PRODUCTCODE_.MANUFACTURER_ AS MANUFACTURER_,
PRODUCTLINE_.CREATION_DATE_ AS CREATION_DATE_,
ROW_NUMBER() OVER (ORDER BY PRODUCTCODE_.CATEGORY_) AS ROWNUMBER_,
TOTALROWS_ = COUNT(*) OVER()
FROM
PRODUCTCODE_
INNER JOIN
PRODUCTLINE_ ON PRODUCTLINE_.ID_ = PRODUCTCODE_.PRODUCTLINE_ID_
) _tmpList
WHERE
ROWNUMBER_ >= #startingWith
ORDER BY CATEGORY_
";
I am using a C# console app to get some data from a MySql database and I have some problems getting a query right
As it is now:
SELECT * FROM Customer
WHERE EXISTS ( SELECT * FROM Customer_x_Billing c WHERE Customer.`customer id` = c.customer_id)
AND 2011 -04 -03 < ( SELECT last_changed FROM Customer_x_Billing c WHERE Customer.`customer id` = c.customer_id )
ORDER BY Customer.`customer id`
How can I improve this one?
I want to get all customers that has their ID in both Customer and Customer_x_Billing table and where the last_changed date in Customer_x_Billing is greater than a parameter (2011-04-03 in this case). If I set the date to 2012-04-03 it shouldn't return any row but it returns all records that match the first condition (exist in both).
Try below one
SELECT * FROM Customer
INNER JOIN
Customer_x_Billing ON Customer.`customer id` = Customer.customer_id
WHERE last_changed > 2011 -04 -03
ORDER BY Customer.`customer id`
problem with you query is you are scanning Customer_x_Billing table two time which is not needed, its better to go for one inner join which will stisfy you first condition the exists one and second satisfy by writing the where clause.
SELECT c.* FROM Customer c INNER JOIN Customer_x_Billing cb ON cb.customer_id = c.id WHERE DATE(cb.last_changed) > '2011-04-03' ORDER BY c.id;
If I read your question right I belive you can achieve this with an INNER JOIN...
SELECT *
FROM Customer c
INNER JOIN Customer_x_Billing b
ON c.customer_id = b.customer_id
WHERE last_changed_date > '2011-04-03'
SELECT Customer.* FROM Customer c INNER JOIN Customer_x_Billing b
ON c.`customer id`=b.`customer id`
WHERE last_changed>'2011-04-03'
ORDER BY c.`customer id`
Anyway beware of dates in your query...
More or less like this.
using (SqlConnection con = new SqlConnection(connectionString))
{
using (SqlCommand cmd = new SqlCommand())
{
cmd.Connection = con;
cmd.CommandText
= "SELECT * FROM Custromer c JOIN Customer_x_Billing cb ON c.'customer id' = cd.'customer id' Where last_change < #lastChangeDate";
cmd.Parameters.AddWithValue("#lastChangeDate", new DateTime(2011,04,03));
using (SqlDataReader drd = cmd.ExecuteReader())
{
while (drd.Read())
{
// Read from data reader
}
}
}
}
For sake of your application you should get familiar with some database tutorial, and try to understand the concept of relational databases.