I am retrieving data from SQL Server from a StoredProcedure using Dapper and I'm getting error
Specified cast is not valid.
and details:
Error parsing column 4 (SubTotal=0.00 - Decimal)
On SQL Server side the column SubTotal is decimal(18, 2) NULLABLE and on .NET side it's decimal?. The data being retrieved is 0.00.
I checked this answer: Dapper,decimal to double? Error parsing column X
As per answer, I replaced
il.Emit(OpCodes.Ldtoken, unboxType);
with
il.Emit(OpCodes.Ldtoken, Nullable.GetUnderlyingType(unboxType) ?? unboxType);
on line 2360 and still getting the same error.
Anyone has any ideas about this? Thanks.
Update:
I tried making column non-nullable. Also tried changing column to float (on SQL Server) and double (on .NET side). None of these worked and I was getting the same error. Then I changed column to int and now code works fine. However, I'm working with monetary values and would like to use floating point numbers. Will investigate further...
I'm executing a stored procedure as follows
var transaction = this.db.Query<PaymentTransactions>("usp_PaymentTransactionsGetSingleIfPaid", new { registrationId }, commandType: CommandType.StoredProcedure);
The relevant part of the stored procedure that returns information is below.
SELECT * FROM PaymentTransactions WHERE RegistrationId = #registrationId AND TransactionStatus = 'SUCCESS';
UPDATE 2:
Dapper is working fine. Maybe there was something wrong with my dev environment. All it took was VS restart.
Don't laugh, but I had this exact same problem with Dapper in an ASP.NET MVC project and the solution as in the comment from #erdinger worked also for me:
Close Visual Studio
Start Visual Studio again
The problem was fixed this way...
Seems like this is not Dapper specific, as I just verified the below snippet works as expected.
Try enumerating your column names explictly (instead of select *) so that the procedure returns exactly what should be mapped to PaymentTransactions. Its possible there is another non-decimal column that is misnamed?
This is using Dapper v1.13 on .Net45:
Procedure:
create procedure dbo.Test
as
select [SubTotal] = cast('0.01' as decimal(18,2))
union all
select null;
Linqpad:
void Main()
{
using (IDbConnection cnn = GetOpenConnection())
{
var users = cnn.Query<Sale>("yak.dbo.test", new { }, commandType: CommandType.StoredProcedure);
users.Dump();
}
}
public static readonly string connectionString = "Data Source=.;Initial Catalog=tempdb;Integrated Security=True";
public static IDbConnection GetOpenConnection()
{
var connection = new SqlConnection(connectionString);
connection.Open();
return connection;
}
public class Sale
{
public decimal? SubTotal;
}
Returns:
Related
I ran into another issue with using a data reader around a sproc with multiple ref cursors coming out. I am getting a not supported exception. Unfortunately, i can see from where it is coming from the source code of npgsql however.. i am not sure if i agree with throwing that exception. The code we have written works with oracle (both fully managed and managed flavors), sql server. Any help appreciated to keep it consistent for an api across some of those key flavors of dbms out there.
sproc body
CREATE OR REPLACE FUNCTION public.getmultipleresultsets (
v_organizationid integer)
RETURNS Setof refcursor
LANGUAGE 'plpgsql'
AS $BODY$
declare public override void AddCursorOutParameter(DbCommand command,
string RefCursorName)
{
NpgsqlParameter parameter = (NpgsqlParameter)CreateParameter(RefCursorName, false);
parameter.NpgsqlDbType = NpgsqlDbType.Refcursor;
parameter.NpgsqlValue = DBNull.Value;
parameter.Direction = ParameterDirection.Output;
command.Parameters.Add(parameter);
}
cv_1 refcursor;
cv_2 refcursor;
BEGIN
open cv_1 for
SELECT a.errorCategoryId, a.name, a.bitFlag
FROM ErrorCategories a
ORDER BY name;
RETURN next cv_1;
open cv_2 for
SELECT *
FROM StgNetworkStats ;
RETURN next cv_2;
END;
$BODY$;
Key Reader code that wraps postgres sql (Entlib implementation of npgsql)
private IDataReader DoExecuteReader(DbCommand command, CommandBehavior cmdBehavior)
{
try
{
var sql = new StringBuilder();
using (var reader = command.ExecuteReader(CommandBehavior.SequentialAccess))
{
while (reader.Read())
{
sql.AppendLine($"FETCH ALL IN \"{ reader.GetString(0) }\";");
}
}
command.CommandText = sql.ToString();
command.CommandType = CommandType.Text;
IDataReader reader2 = command.ExecuteReader(cmdBehavior);
return reader2;
}
catch (Exception)
{
throw;
}
}
The command building code is shown below
Helper.InitializeCommand(cmd, 300, "getmultipleresultsets");
db.AddReturnValueParameter(cmd);
db.AddInParameter(cmd, "organizationId", DbType.Int32, ORGANIZATIONID);
db.AddCursorOutParameter(cmd, "CV_1");
db.AddCursorOutParameter(cmd, "CV_2
The code that adds the refcursor parameter goes something like this
You code above seems to garble the PostgreSQL function with the .NET client code attempting to read its result.
Regardless, your function is declared to return a set of refcursors - this is not the same as two output parameters; you seem to be confusing the name of the cursor (cursors have names, but not ints, for example) with the name of the parameter (int parameters do have names).
Please note that PostgreSQL does not actually have output parameters - a function always returns a single table, and that's it. PostgreSQL does have a function syntax with output parameters, but that is only a way to construct the schema of the output table. This is unlike SQL Server, which apparently can return both a table and a set of named output parameters. To facilitate portability, when reading results, if Npgsql sees any NpgsqlParameter with direction out, it will attempt to find a resultset with the name of the parameter and will simply populate the NpgsqlParameter's Value with the first row's value for that column. This practice has zero added value over simply reading the resultset yourself - it's just there for compatibility.
To sum it up, I'd suggest you read the refcursors with your reader and then fetch their results as appropriate.
I am a rookie/newbie in the postgres data access api. I have worked a bit on oracle, sql server and trying to do what i have done with those dbms
The use is very simple
1) a stored procedure aka function with input params
2) Returning or more ref cursors
3) Using an ent lib wrapper to use the npgsql provider/database with it
4) Doing a data adapter fill and running into the issue with some cursor de-referencing.. it appears though i am inside a tran..
5) I just want to get some simple working sample with the latest npgsql provider..
Here is my function
CREATE OR REPLACE FUNCTION public.geterrorcategories(
v_organizationid integer)
RETURNS refcursor
LANGUAGE 'plpgsql'
AS $BODY$
DECLARE cv_1 refcursor;
BEGIN
open cv_1 for
SELECT errorCategoryId, name, bitFlag
FROM ErrorCategories
ORDER BY name;
RETURN cv_1;
END;
$BODY$;
The code using the enterprise lib api/wrapper is as follows.
/// <summary>
/// Executes GetErrorCategories in case of SQL Server or GetErrorCategories for Oracle
/// </summary>
public static DataTable GetErrorCategoriesAsDataTable(string dbKey ,int? ORGANIZATIONID)
{
DataTable tbl = new DataTable();
Database db = Helper.GetDatabase(dbKey);
using (DbConnection con = db.CreateConnection()){
con.Open();
var tran = con.BeginTransaction();
using (DbCommand cmd = con.CreateCommand()){
cmd.Transaction = tran;
BuildGetErrorCategoriesCommand(db, cmd ,ORGANIZATIONID);
cmd.CommandText = "GetErrorCategories";
try {
Helper.FillDataTable(tbl, db, cmd);
con.Close();
} catch (DALException ) {
throw;
}
}
}
return tbl;
}
The command is built as follows.
private static void BuildGetErrorCategoriesCommand(Database db, DbCommand cmd ,int? ORGANIZATIONID){
Helper.InitializeCommand(cmd, 300, "GetErrorCategories");
db.AddReturnValueParameter(cmd);
db.AddInParameter(cmd, "organizationId", DbType.Int32, ORGANIZATIONID);
db.AddCursorOutParameter(cmd, "CV_1");
}
I am not getting any error. I get only 1 row back which i think is this un_named_portal_1 or something but not the results from my table which my query returns
It is frustrating as i would like to keep my application code the same as much as possible but would like to switch providers at run time. I am using a tweaked 'ent lib' contribution database that was created for npgsql.
Hope this helps to point me to the right areas to look for..
There is absolutely no reason above to declare your PostgreSQL function to return a cursor - you can simply return a table, see the PostgreSQL docs for more info.
Npgsql originally had a feature where it automatically "dereferenced" cursors returned from functions, but this has been removed. For more information about this see this issue (warning, it's long...). Some people are requesting that the feature be returned.
I am using SQL Server 2016.
I have a stored procedure GET_RECORDS that takes input parameters for filter and outputs a CURSOR parameter
I want to get this cursor in my SSIS package
I had created data flow task, OleDb source and variables for parameter values. Then mapped parameters
Params mapping screen
but when I wanted to save the component - I got an error
error screen
I tried to add clause WITH RESULT SETS with some dummy columns, but my procedure doesn't return any result set
What am I doing wrong?
Any advices will be helpful.
Thank you.
With regards, Yuriy.
The source component is trying to determine what columns and types will be returned. Because you are using dynamic SQL the metadata can change each time you run it.
With result sets allows you to define the data being returned but should only be used if you are guaranteed to have those results every time you execute.
EDIT:
I create a connection and run the command so that it populates a data table. Then I put the column headers into a string array. There are plenty of examples out there.
Then I use the following function to create a destination table. Finally I create a datareader and pass that to the .Net SqlBulkCopy. Hope this helps.
private void CreateTable(string TableName, string[] Fields)
{
if (TableExists(TableName) && Overwrite)
{
SqlCommand = new SqlCommand($"Drop Table [{TableName}]", SqlConnection);
SqlCommand.ExecuteNonQuery();
}
string Sql = $"Create Table [{TableName}] (";
int ColumnNumber = 1;
foreach (string Field in Fields)
{
string FieldValue = Field;
if (! HasHeaders)
{
FieldValue = "Column" + ColumnNumber;
ColumnNumber++;
}
Sql += $"[{FieldValue}] Varchar(8000),";
}
Sql = Sql + "ImportFileID Int, ID Int Identity(1,1) Not Null, Constraint [PK_" + TableName + "] Primary Key Clustered ([ID] Asc))";
SqlCommand = new SqlCommand(Sql, SqlConnection);
SqlCommand.ExecuteNonQuery();
}
Use ado.net source instead of oledb source, define a simple select and get the columns you wish to return. Now you can define expresión in the dataflow properties.
Search ado.net source dynamic sql
:)
try to return the records and use foreach in ETL instead of cursor
https://www.simple-talk.com/sql/ssis/implementing-foreach-looping-logic-in-ssis/
I think you can do it from a simple way, but I don't know what you are you doing, exactly...
I have a customer setup that uses stored procedures to return data from its SQL Server database.
Those stored procedures are all built the same way - they take a bunch of input parameters, and they return:
the first is just a single row, single column with the result code (type INT) - 0 for success, some other values otherwise; if the value is 0, then there's a second result set that contains the actual data
the second result set can be anything - any number of columns and rows
I'm trying to create a "generic" way to interface with this system, and my attempt is this:
create a class that takes stored procedure name and input parameters
a return type that contains both an ErrorCode INT property as well as a DataTable results property
However, I'm having trouble getting this to work with ADO.NET and SQL Server 2008 R2.
My code boils down to this:
public MyResultType CallService(string procedureName, MyParameters parameters)
{
MyResultType result = new MyResultType { ErrorCode = 0 };
using (SqlConnection conn = new SqlConnection(_connectionString))
using (SqlCommand cmd = new SqlCommand(procedureName, conn))
{
cmd.CommandType = CommandType.StoredProcedure;
SetupParameters(cmd, parameters);
// open connection, execute the stored procedure
conn.Open();
using (SqlDataReader rdr = cmd.ExecuteReader())
{
// get the first result set - the status code, one row, one column of type INT
while (rdr.Read())
{
result.ErrorCode = rdr.GetInt32(0);
}
// if we got a "0" (success) -> go to the next result set and load it into the table
if(result.ErrorCode == 0 && rdr.NextResult())
{
result.ResultTable = new DataTable();
result.ResultTable.Load(rdr);
int colCount = result.ResultTable.Columns.Count;
int rowCount = result.ResultTable.Rows.Count;
}
rdr.Close();
}
conn.Close();
}
return result;
}
My issue is: the call to the stored procedure works just fine, the error code = 0 is picked up just fine, the data table is created and the number of columns is the expected value - but there are NO ROWS loaded...
I've been trying everything I can think of to get those rows into the DataTable - no luck. And of course - if I execute this very same stored procedure in SQL Server Management Studio, everything works just fine, I get my ErrorCode=0 and my result set of 18 columns and 5 rows - no problem....
What am I missing? Can anyone spot the problem in my code? Why aren't the rows of the second result set loaded (but the columns are being detected, it seems)?
The code as published works fine - there was a difference between how I call it from C# and in SQL Server Management Studio : NULL handling.
I had some input parameters set to int and thus provided a 0 value to the stored procedure, while it really expected to get a NULL if the value isn't defined......
Stupid rookie mistake..... SORRY GUYS! And thanks for your inputs!
The DataTable.Load method implicitly calls the NextResult method, so combining that with your explicit call, it is advancing to a resultset that isn't there. You should remove your own call to NextResult if you want to use DataTable.Load or loop through and fill a datatable yourself.
In my application I need to get database date(sysdate in case of Oracle DB) and compare it with user input date (String converted to java.util.Date). From this forum I got the following code which helps in the case of Oracle dialect.
public Date getDate() {
Session session = getHibernateTemplate().getSessionFactory().openSession();
SQLQuery query = session.createSQLQuery("select sysdate as mydate from dual");
query.addScalar("mydate", Hibernate.TIMESTAMP);
return (Date) query.uniqueResult();
}
And from this link got the following method which uses mapping file with formula.
<property name="currentDate" formula="(select sysdate from dual)"/>
Again this is specific to Oracle. I think using later method is more performance friendly, because we can get it from the same session, i.e no need of opening another session just for getting date.
I am looking for a generic solution to get date, time and timestamp from any DBMS using Hibernate. Using HQL is the preferred. Hope such a solution is available.
For those who are looking for .NET /C# solution, here is what worked for me:
// this works only with Oracle
public DateTime DbTimeStamp(ISession session)
{
// Sample returned value = "12-OCT-11 01.05.54.365134000 AM -07:00"
string sql = "SELECT SYSTIMESTAMP FROM DUAL";
ISQLQuery query = session.CreateSQLQuery(sql)
.AddScalar("SYSTIMESTAMP", NHibernate.NHibernateUtil.DateTime);
return query.UniqueResult<DateTime>();
}