Reusing SqlCommand? - c#

I am not really sure if this is possible or not.
I am currently working on a college project and I have a function that uses stored procedures. I would like to know if it is possible to take the same SqlCommand instance and apply updated parameters to call into the stored procedure again within the same function.
Lets say i have something like this in my code:
myConStr = ConfigurationManager.ConnectionStrings["MyConnString"].ConnectionString;
myConn = new SqlConnection(myConStr);
myCommand = new System.Data.SqlClient.SqlCommand("team5UserCurrentBooks3", myConn);
myCommand.CommandType = CommandType.StoredProcedure;
myCommand.Parameters.AddWithValue("#book_id", bookID);
myCommand.Parameters.AddWithValue("#user_id", userID);
try
{
myConn.Open();
myCommand.ExecuteNonQuery();
Is it possible to update MyCommand's parameters and call the stored procedure again?

Yes. You'll want to make sure that you call myCommand.Parameters.Clear between each call in order to dump the parameters, but there's nothing stopping you from reusing the object. (I don't use C# often, so this may have an error or two in the text)
myConStr = ConfigurationManager.ConnectionStrings["MyConnString"].ConnectionString;
myConn = new SqlConnection(myConStr);
myConn.Open();
myCommand = new System.Data.SqlClient.SqlCommand("team5UserCurrentBooks3", myConn);
myCommand.CommandType = CommandType.StoredProcedure;
myCommand.Parameters.AddWithValue("#book_id", bookID);
myCommand.Parameters.AddWithValue("#user_id", userID);
myCommand.ExecuteNonQuery();
myCommand.Parameters.Clear();
myCommand.CommandText= "NewStoredProcedureName";
myCommand.CommandType = CommandType.StoredProcedure;
myCommand.Parameters.AddWithValue("#foo_id", fooId);
myCommand.Parameters.AddWithValue("#bar_id", barId);
mycommand.ExecuteNonQuery();
myCommand.Parameters.Clear();
myCommand.CommandText = " SELECT * FROM table1 WHERE ID = #TID;"
myCommand.CommandType = CommandType.Text;
myCommand.Parameters.AddWithValue("#tid", tId);
SqlReader rdr;
rdr = myCommand.ExecuteReader();

Yes! You can definitely do that. Within a function you can re-use the same connection as well (I don't recommend re-using a connection object for larger scopes, but it is possible).
You could also do something like this:
myConStr = ConfigurationManager.ConnectionStrings["MyConnString"].ConnectionString;
using (var cn = new SqlConnection(myConStr) )
using (var cmd = new SqlCommand("team5UserCurrentBooks3", cn) )
{
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("#user_id", SqlDbType.Int).Value = userID;
cmd.Parameters.Add("#book_id", SqlDbType.Int);
cn.Open();
for(int i = 0; i<10; i++)
{
cmd.Parameters["#book_id"].Value = i;
cmd.ExecuteNonQuery();
}
}
This will run the query 10 times and use the same user_id each time it executes, but change the book_id. The using block is just like wrapping your connection in a try/catch to make sure it's closed.

Related

Execute/ Call Oracle Procedure In C# [duplicate]

How does one call a stored procedure in oracle from C#?
Please visit this ODP site set up by oracle for Microsoft OracleClient Developers:
http://www.oracle.com/technetwork/topics/dotnet/index-085703.html
Also below is a sample code that can get you started to call a stored procedure from C# to Oracle. PKG_COLLECTION.CSP_COLLECTION_HDR_SELECT is the stored procedure built on Oracle accepting parameters PUNIT, POFFICE, PRECEIPT_NBR and returning the result in T_CURSOR.
using Oracle.DataAccess;
using Oracle.DataAccess.Client;
public DataTable GetHeader_BySproc(string unit, string office, string receiptno)
{
using (OracleConnection cn = new OracleConnection(DatabaseHelper.GetConnectionString()))
{
OracleDataAdapter da = new OracleDataAdapter();
OracleCommand cmd = new OracleCommand();
cmd.Connection = cn;
cmd.InitialLONGFetchSize = 1000;
cmd.CommandText = DatabaseHelper.GetDBOwner() + "PKG_COLLECTION.CSP_COLLECTION_HDR_SELECT";
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("PUNIT", OracleDbType.Char).Value = unit;
cmd.Parameters.Add("POFFICE", OracleDbType.Char).Value = office;
cmd.Parameters.Add("PRECEIPT_NBR", OracleDbType.Int32).Value = receiptno;
cmd.Parameters.Add("T_CURSOR", OracleDbType.RefCursor).Direction = ParameterDirection.Output;
da.SelectCommand = cmd;
DataTable dt = new DataTable();
da.Fill(dt);
return dt;
}
}
I have now got the steps needed to call procedure from C#
//GIVE PROCEDURE NAME
cmd = new OracleCommand("PROCEDURE_NAME", con);
cmd.CommandType = CommandType.StoredProcedure;
//ASSIGN PARAMETERS TO BE PASSED
cmd.Parameters.Add("PARAM1",OracleDbType.Varchar2).Value = VAL1;
cmd.Parameters.Add("PARAM2",OracleDbType.Varchar2).Value = VAL2;
//THIS PARAMETER MAY BE USED TO RETURN RESULT OF PROCEDURE CALL
cmd.Parameters.Add("vSUCCESS", OracleDbType.Varchar2, 1);
cmd.Parameters["vSUCCESS"].Direction = ParameterDirection.Output;
//USE THIS PARAMETER CASE CURSOR IS RETURNED FROM PROCEDURE
cmd.Parameters.Add("vCHASSIS_RESULT",OracleDbType.RefCursor,ParameterDirection.InputOutput);
//CALL PROCEDURE
con.Open();
OracleDataAdapter da = new OracleDataAdapter(cmd);
cmd.ExecuteNonQuery();
//RETURN VALUE
if (cmd.Parameters["vSUCCESS"].Value.ToString().Equals("T"))
{
//YOUR CODE
}
//OR
//IN CASE CURSOR IS TO BE USED, STORE IT IN DATATABLE
con.Open();
OracleDataAdapter da = new OracleDataAdapter(cmd);
da.Fill(dt);
Hope this helps
It's basically the same mechanism as for a non query command with:
command.CommandText = the name of the
stored procedure
command.CommandType
= CommandType.StoredProcedure
As many calls to command.Parameters.Add as the number of parameters the sp requires
command.ExecuteNonQuery
There are plenty of examples out there, the first one returned by Google is this one
There's also a little trap you might fall into, if your SP is a function, your return value parameter must be first in the parameters collection
Connecting to Oracle is ugly. Here is some cleaner code with a using statement. A lot of the other samples don't call the IDisposable Methods on the objects they create.
using (OracleConnection connection = new OracleConnection("ConnectionString"))
using (OracleCommand command = new OracleCommand("ProcName", connection))
{
command.CommandType = CommandType.StoredProcedure;
command.Parameters.Add("ParameterName", OracleDbType.Varchar2).Value = "Your Data Here";
command.Parameters.Add("SomeOutVar", OracleDbType.Varchar2, 120);
command.Parameters["return_out"].Direction = ParameterDirection.Output;
command.Parameters.Add("SomeOutVar1", OracleDbType.Varchar2, 120);
command.Parameters["return_out2"].Direction = ParameterDirection.Output;
connection.Open();
command.ExecuteNonQuery();
string SomeOutVar = command.Parameters["SomeOutVar"].Value.ToString();
string SomeOutVar1 = command.Parameters["SomeOutVar1"].Value.ToString();
}
This Code works well for me calling oracle stored procedure
Add references by right clicking on your project name in solution explorer >Add Reference >.Net then Add namespaces.
using System.Data.OracleClient;
using System.Data;
then paste this code in event Handler
string str = "User ID=username;Password=password;Data Source=Test";
OracleConnection conn = new OracleConnection(str);
OracleCommand cmd = new OracleCommand("stored_procedure_name", conn);
cmd.CommandType = CommandType.StoredProcedure;
--Ad parameter list--
cmd.Parameters.Add("parameter_name", "varchar2").Value = value;
....
conn.Open();
cmd.ExecuteNonQuery();
And its Done...Happy Coding with C#
In .Net through version 4 this can be done the same way as for SQL Server Stored Procs but note that you need:
using System.Data.OracleClient;
There are some system requirements here that you should verify are OK in your scenario.
Microsoft is deprecating this namespace as of .Net 4 so third-party providers will be needed in the future. With this in mind, you may be better off using Oracle Data Provider for .Net (ODP.NET) from the word go - this has optimizations that are not in the Microsoft classes. There are other third-party options, but Oracle has a strong vested interest in keeping .Net developers on board so theirs should be good.
Instead of
cmd = new OracleCommand("ProcName", con);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("ParName", OracleDbType.Varchar2, ParameterDirection.Input).Value = "foo";
You can also use this syntax:
cmd = new OracleCommand("BEGIN ProcName(:p0); END;", con);
cmd.CommandType = CommandType.Text;
cmd.Parameters.Add("ParName", OracleDbType.Varchar2, ParameterDirection.Input).Value = "foo";
Note, if you set cmd.BindByName = False (which is the default) then you have to add the parameters in the same order as they are written in your command string, the actual names are not relevant. For cmd.BindByName = True the parameter names have to match, the order does not matter.
In case of a function call the command string would be like this:
cmd = new OracleCommand("BEGIN :ret := ProcName(:ParName); END;", con);
cmd.CommandType = CommandType.Text;
cmd.Parameters.Add("ret", OracleDbType.RefCursor, ParameterDirection.ReturnValue);
cmd.Parameters.Add("ParName", OracleDbType.Varchar2, ParameterDirection.Input).Value = "foo";
// cmd.ExecuteNonQuery(); is not needed, otherwise the function is executed twice!
var da = new OracleDataAdapter(cmd);
da.Fill(dt);
Below worked for me in .NET Core solution. Note that it uses OracleDataReader and Oracle CommandType is CommandType.Text
using Oracle.ManagedDataAccess.Client;
.......
string spSql = "BEGIN STORED_PROC_NAME(:IN_PARAM, :OUT_PARAM1, :OUT_PARAM2); END; ";
using (OracleConnection oraCnn = new OracleConnection(cnnString))
using (OracleCommand oraCommand = new OracleCommand(spSql, oraCnn))
{
await oraCnn.OpenAsync(cancellationToken);
oraCommand.CommandType = CommandType.Text;
oraCommand.BindByName = true;
oraCommand.Parameters.Add("IN_PARAM", OracleDbType.Long, ParameterDirection.Input).Value = 123;
oraCommand.Parameters.Add("OUT_PARAM1", OracleDbType.Int32, null, ParameterDirection.Output);
oraCommand.Parameters.Add("OUT_PARAM2", OracleDbType.Varchar2, 4000, null, ParameterDirection.Output);
OracleDataReader objReader = oraCommand.ExecuteReader();
string outParamValue= oraCommand.Parameters["OUT_PARAM2"].Value.ToString();
}

How to send and receive parameters to/from SQL Server stored procedure

IN THE LAST PART I WROTE THE working solution:
I have this stored procedure in SQL Server :
alter PROCEDURE [dbo].[ProcedureName]
#v nvarchar(10),
#L NVarChar(2)
AS
BEGIN
SET NOCOUNT ON;
SELECT B,M,V
FROM XXXX
WHERE V = #v and L = #L
END
and I am passing the parameters but I cannot retrieve the SELECT part I need to retrieve B,M,V of Select B,M,V also
SqlCommand Cmd = new SqlCommand("ProcedureName", cnn);
Cmd.CommandType = CommandType.StoredProcedure;
Cmd.Parameters.Add("#v", SqlDbType.NVarChar, 10).Value = v;
Cmd.Parameters.Add("#L", SqlDbType.NVarChar, 2).Value = lo;
if (Cmd.Connection.State == ConnectionState.Closed)
{
Cmd.Connection.Open();
}
Cmd.ExecuteNonQuery();
THIS IS THE WOKING SOLUTION THANKS TO THE HELP I GOT HERE :
SqlCommand Cmd = new SqlCommand("ProcedureName", cnn);
Cmd.CommandType = CommandType.StoredProcedure;
Cmd.Parameters.Add("#v", SqlDbType.NVarChar, 10).Value = v;
Cmd.Parameters.Add("#L", SqlDbType.NVarChar, 2).Value = lo;
if (Cmd.Connection.State == ConnectionState.Closed)
{
Cmd.Connection.Open();
}
using (SqlDataReader reader = Cmd.ExecuteReader())
{
if (reader.HasRows)
{
while (reader.Read())
{
ret = new MYCLASS();
ret.B = reader.GetString(0);
ret.M = reader.GetString(1);
ret.V = reader.GetString(2);
}
}
}
You'll need to make use of SqlDataReader to achieve this. Also make use of using block to ensure the connection object is closed and disposed correctly.
From MSDN
To ensure that connections are always closed, open the connection inside of a using block, as shown in the following code fragment. Doing so ensures that the connection is automatically closed when the code exits the block.
You can change your code to something like:
using(var con = new SqlConnection("ConnectionString")) {
using(var cmd = new SqlCommand("ProcedureName", con)) {
//Params here
con.Open();
using(var reader = cmd.ExecuteReader()) {
while (reader.Read()) {
var bValue = reader.GetString(0);
//Same for the next two values
}
}
}
}
You're almost there, now if you pay close attention to your code you're not using the correct method for your procedure. This can be easily achieved with:
ExecuteReader Since you're only reading from your database.
instead of:
ExecuteNonQuery which is commonly used for UPDATE, INSERT, or DELETE statements

How to use DataAdapter to call a stored procedure in C# with variable parameters

I am calling the following code in C# to fill a dataAdapter with a given stored procedure "sp1_name". The problem is that I want to call different stored procedures with different parameters. (All SP's do a SELECT)
Let's suppose that my stored procedure name is "SP_SOMESP", then everything works fine.
Let's suppose that my stored procedure name is "SP_SOMESP #Month= 10, #Year = 2010", then it doesn't work. It throws an exception that cannot find this stored procedure.
Any solutions?
Thanks!
//First Connection - SP1
using (SqlConnection con = new SqlConnection(conStr))
{
using (SqlCommand cmd = new SqlCommand(sp1_name, con)) //sp1_name = NAME + PARAMETERS
{
cmd.CommandTimeout = 3600;
cmd.CommandType = CommandType.StoredProcedure;
using (SqlDataAdapter dataAdapter = new SqlDataAdapter(cmd))
{
dataAdapter.Fill(results2);
}
}
}
First Issue:
Parameters in a stored procedure shouldn't be included along with its name
Second Issue:
Having a space in names of stored procedure isn't a good practice.
And for code behind
using(SqlConnection con = new SqlConnection("Your Connection String Here"))
{
SqlCommand cmd = new SqlCommand("sp_SomeName", con);
cmd.CommandType = CommandType.StoredProcedure;
//the 2 codes after this comment is where you assign value to the parameters you
//have on your stored procedure from SQL
cmd.Parameters.Add("#MONTH", SqlDbType.VarChar).Value = "someValue";
cmd.Parameters.Add("#YEAR", SqlDbType.VarChar).Value = "SomeYear";
SqlDataAdapter da = new SqlDataAdapter(cmd);
SqlDataSet ds = new SqlDataSet();
da.Fill(ds); //this is where you put values you get from the Select command to a
//dataset named ds, reason for this is for you to fetch the value from DB to code behind
foreach(DataRow dr in ds.Tables[0].Rows) // this is where you run through the dataset and get values you want from it.
{
someTextBox.Text = dr["Month"].ToString(); //you should probably know this code
}
}
You have to add in the parameters programmatically, see SqlCommand.Parameters.
It would be something like
cmd.Parameters.AddWithValue("#Month", 10);
cmd.Parameters.AddWithValue("#Year", 2010);
This would be after the command is declared and before it is executed.
If you find that you need to delcare the data type, then try it this way
cmd.Parameters.Add("#Month", SqlDbType.Int).Value = 10;
Check this,
using (SQLCommand cmd = new SQLCommand())
{
cmd.CommandText = "SP_SOMESP";
cmd.Parameters.Add("#Month", 10);
cmd.Parameters.Add("#Year", 2010);
cmd.CommandTimeout = 3600;
cmd.CommandType = CommandType.StoredProcedure;
cmd.Connection = con;
}
using (SqlDataAdapter dataAdapter = new SqlDataAdapter(cmd))
{
dataAdapter.SelectCommand = cmd;
dataAdapter.Fill(results2);
}

C# SQL, Multiple Commands

I'm trying to write a method which should communicate with database, but I'm not sure if my approach is right.
public void dbWorkerLogin(int workerNumber) {
// Connection string stored in "conn"
if (!new SqlCommand("Some Command WHERE id=" +workernumber,conn).executeReader().HasRows)
{
new SqlCommand("exec STORED_PROCEDURE1 " + workerNumber, conn).ExecuteNonQuery();
new SqlCommand("exec STORED_PROCEDURE2 " + workerNumber, conn).ExecuteNonQuery();
}
else
{
new SqlCommand("exec STORED_PROCEDURE3 " + workerNumber,conn).ExecuteNonQuerry();
}
1) Is it ok to write it like this and start each SqlCommand with keyword new? Or should I do something like:
SqlCommand command = new SqlCommand(null, conn);
command = ...;
and then recycle the variable 'command' or this way?
using(SqlCommand cmd = new SqlCommand("COMMAND", conn);
2) Will my procedures work or should I use SqlCommand.Prepare() function that will covert my data into correct datatypes? eg. workerNumber is int, but in database it is stored as decimal.
using (SqlCommand cmd = new SqlCommand("STORED_PROCEDURE", conn))
{
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parametres.Add("#id", SqlDbType.Decimal).Value = workNumber;
cmd.Prepare();
cmd.ExecuteNonQuery();
}
Can you please somehow sum up what to use, what better not to? Unfortunately I can't test that first code because of limited access to DB so I'm not sure if it can be executed without errors or not.
Thank you for any help on this subject!
EDIT:
After a few hours I reach to this stage:
public int getWorkerNumber(string uniqueID)
{
using (conn = new SqlConnection(ConfigurationManager.ConnectionStrings["dbConnect"].ConnectionString))
{
conn.Open();
using (SqlCommand cmd = new SqlCommand("SELECT number FROM worker WHERE workerID = #id",conn))
{
cmd.Parameters.Add("#id", SqlDbType.Decimal).Value = uniqueID;
using (SqlDataReader reader = cmd.ExecuteReader())
{
int answer;
while (reader.Read())
{
answer = (int)reader.GetDecimal(0);
}
return answer;
}
}
}
}
And this one:
public string dbLoginWorker(int workerNumber)
{
SqlCommand cmd;
SqlDataReader reader;
using (conn = new SqlConnection(ConfigurationManager.ConnectionStrings["dbConnect"].ConnectionString))
{
conn.Open();
cmd = new SqlCommand("SELECT column FROM table WHERE id= #workernumber", conn);
cmd.Parameters.Add("#workernumber", SqlDbType.Decimal).Value = workerNumber;
reader = cmd.ExecuteReader();
if (!reader.HasRows)
{
cmd = new SqlCommand("STORED_PROCEDURE1", conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("#ID", SqlDbType.Decimal).Value = workerNumber;
cmd.Parameters.Add("#VARCHAR", SqlDbType.VarChar).Value = "text";
cmd.Prepare();
reader.Close();
cmd.ExecuteNonQuery();
cmd.Dispose();
reader.Dispose();
return "procedure 1 executed";
else
{
cmd = new SqlCommand("STORED_PROCEDURE2", conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("#ID", SqlDbType.Decimal).Value = workerNumber;
cmd.Parameters.Add("#INT", SqlDbType.SmallInt).Value = 1;
cmd.Parameters.Add("#VARCHAR", SqlDbType.VarChar).Value = "text";
cmd.Prepare();
reader.Close();
cmd.ExecuteNonQuery();
cmd.Dispose();
reader.Dispose();
return "procedure 2 executed";
}
}
}
Both methods are functional (if I did no mistake in rewriting :) ). I'm not sure which of these methods (1st or 2nd) are better in terms of stability and if this approach is better and more ressistant to SQL Injection. Can someone comment on this subject? Thank you again for any help!
1) It is best to always use USING blocks when possible. This includes SqlConnection, SqlCommand, SqlReader and other objects that implement IDisposable. USING blocks automatically close and dispose of the objects, so you do not have to do so.
2) I believe that you are using the Prepare() method in the wrong place. Look at the following StackOverflow article for proper usage:
PrepareMethodInstructions.
3) in the dbLoginWorker() method, the first query is just used to determine if rows are found. Therefore, I suggest changing the SELECT command to SELECT TOP 1 column FROM table WHERE id= #workernumber so that the query is faster and more efficient.
4) I do not believe your commands are subject to SQL Injection attacks because they are fully parameterized. Good job on that one.
5) As a general thought, I suggest reading up on refactoring techniques. Your dbLoginWorker() method could be made more readable and maintainable, as well as self-documenting, if you created three additional methods, one for each SQL command, and named them something appropriate. You could also setup a method for creating a connection based on a connection name, and you would not have as much duplicate code. For example:
public static SqlConnection GetConnection(string connectionName)
{
SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings[connectionName].ConnectionString);
conn.Open();
return conn;
}
public string dbLoginWorker(int workerNumber)
{
using (conn = GetConnection("dbConnect"))
{
if (CanFindWorkerNumber(conn, workerNumber))
ExecuteProcedure1(conn);
else
ExecuteProcedure2(conn);
}
}
public bool CanFindWorkerNumber (SqlConnection conn, int workerNumber)
{
bool success = false;
using (SqlCommand cmd = new SqlCommand("SELECT TOP 1 column FROM table WHERE id= #workernumber", conn))
{
cmd.Parameters.Add("#workernumber", SqlDbType.Decimal);
cmd.Prepare();
cmd.Parameters[0].Value = workerNumber;
success = cmd.ExecuteScalar() != null;
}
return success;
}
public void ExecuteProcedure1(SqlConnection conn)
{
using (SqlCommand cmd = new SqlCommand("STORED_PROCEDURE1", conn))
{
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("#ID", SqlDbType.Decimal);
cmd.Parameters.Add("#VARCHAR", SqlDbType.VarChar);
cmd.Prepare();
cmd.Parameters[0].Value = workerNumber;
cmd.Parameters[1].Value = "text";
cmd.ExecuteNonQuery();
}
}
public void ExecuteProcedure1(SqlConnection conn)
{
using (SqlCommand cmd = new SqlCommand("STORED_PROCEDURE1", conn))
{
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("#ID", SqlDbType.Decimal);
cmd.Parameters.Add("#INT", SqlDbType.SmallInt).Value);
cmd.Parameters.Add("#VARCHAR", SqlDbType.VarChar);
cmd.Prepare();
cmd.Parameters[0] = workerNumber;
cmd.Parameters[1] = 1;
cmd.Parameters[2] = "text";
cmd.ExecuteNonQuery();
}
}
You could actually do this in one SQL commend. Right now you are pulling back a result set only to see if it has rows or not, then executing different commands based on that. You should be able to do that in one command, disposing of it and the connection appropriately:
var sql =
#"
IF EXISTS(Some Command WHERE id=#workernumber)
BEGIN
exec STORED_PROCEDURE1 #workernumber;
exec STORED_PROCEDURE2 #workernumber;
END
ELSE
exec STORED_PROCEDURE3 #workernumber;
";
Note that you're not vulnerable to SQL injection because you're not dealing with strings, only integers.

Calling Oracle stored procedure from C#?

How does one call a stored procedure in oracle from C#?
Please visit this ODP site set up by oracle for Microsoft OracleClient Developers:
http://www.oracle.com/technetwork/topics/dotnet/index-085703.html
Also below is a sample code that can get you started to call a stored procedure from C# to Oracle. PKG_COLLECTION.CSP_COLLECTION_HDR_SELECT is the stored procedure built on Oracle accepting parameters PUNIT, POFFICE, PRECEIPT_NBR and returning the result in T_CURSOR.
using Oracle.DataAccess;
using Oracle.DataAccess.Client;
public DataTable GetHeader_BySproc(string unit, string office, string receiptno)
{
using (OracleConnection cn = new OracleConnection(DatabaseHelper.GetConnectionString()))
{
OracleDataAdapter da = new OracleDataAdapter();
OracleCommand cmd = new OracleCommand();
cmd.Connection = cn;
cmd.InitialLONGFetchSize = 1000;
cmd.CommandText = DatabaseHelper.GetDBOwner() + "PKG_COLLECTION.CSP_COLLECTION_HDR_SELECT";
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("PUNIT", OracleDbType.Char).Value = unit;
cmd.Parameters.Add("POFFICE", OracleDbType.Char).Value = office;
cmd.Parameters.Add("PRECEIPT_NBR", OracleDbType.Int32).Value = receiptno;
cmd.Parameters.Add("T_CURSOR", OracleDbType.RefCursor).Direction = ParameterDirection.Output;
da.SelectCommand = cmd;
DataTable dt = new DataTable();
da.Fill(dt);
return dt;
}
}
I have now got the steps needed to call procedure from C#
//GIVE PROCEDURE NAME
cmd = new OracleCommand("PROCEDURE_NAME", con);
cmd.CommandType = CommandType.StoredProcedure;
//ASSIGN PARAMETERS TO BE PASSED
cmd.Parameters.Add("PARAM1",OracleDbType.Varchar2).Value = VAL1;
cmd.Parameters.Add("PARAM2",OracleDbType.Varchar2).Value = VAL2;
//THIS PARAMETER MAY BE USED TO RETURN RESULT OF PROCEDURE CALL
cmd.Parameters.Add("vSUCCESS", OracleDbType.Varchar2, 1);
cmd.Parameters["vSUCCESS"].Direction = ParameterDirection.Output;
//USE THIS PARAMETER CASE CURSOR IS RETURNED FROM PROCEDURE
cmd.Parameters.Add("vCHASSIS_RESULT",OracleDbType.RefCursor,ParameterDirection.InputOutput);
//CALL PROCEDURE
con.Open();
OracleDataAdapter da = new OracleDataAdapter(cmd);
cmd.ExecuteNonQuery();
//RETURN VALUE
if (cmd.Parameters["vSUCCESS"].Value.ToString().Equals("T"))
{
//YOUR CODE
}
//OR
//IN CASE CURSOR IS TO BE USED, STORE IT IN DATATABLE
con.Open();
OracleDataAdapter da = new OracleDataAdapter(cmd);
da.Fill(dt);
Hope this helps
It's basically the same mechanism as for a non query command with:
command.CommandText = the name of the
stored procedure
command.CommandType
= CommandType.StoredProcedure
As many calls to command.Parameters.Add as the number of parameters the sp requires
command.ExecuteNonQuery
There are plenty of examples out there, the first one returned by Google is this one
There's also a little trap you might fall into, if your SP is a function, your return value parameter must be first in the parameters collection
Connecting to Oracle is ugly. Here is some cleaner code with a using statement. A lot of the other samples don't call the IDisposable Methods on the objects they create.
using (OracleConnection connection = new OracleConnection("ConnectionString"))
using (OracleCommand command = new OracleCommand("ProcName", connection))
{
command.CommandType = CommandType.StoredProcedure;
command.Parameters.Add("ParameterName", OracleDbType.Varchar2).Value = "Your Data Here";
command.Parameters.Add("SomeOutVar", OracleDbType.Varchar2, 120);
command.Parameters["return_out"].Direction = ParameterDirection.Output;
command.Parameters.Add("SomeOutVar1", OracleDbType.Varchar2, 120);
command.Parameters["return_out2"].Direction = ParameterDirection.Output;
connection.Open();
command.ExecuteNonQuery();
string SomeOutVar = command.Parameters["SomeOutVar"].Value.ToString();
string SomeOutVar1 = command.Parameters["SomeOutVar1"].Value.ToString();
}
This Code works well for me calling oracle stored procedure
Add references by right clicking on your project name in solution explorer >Add Reference >.Net then Add namespaces.
using System.Data.OracleClient;
using System.Data;
then paste this code in event Handler
string str = "User ID=username;Password=password;Data Source=Test";
OracleConnection conn = new OracleConnection(str);
OracleCommand cmd = new OracleCommand("stored_procedure_name", conn);
cmd.CommandType = CommandType.StoredProcedure;
--Ad parameter list--
cmd.Parameters.Add("parameter_name", "varchar2").Value = value;
....
conn.Open();
cmd.ExecuteNonQuery();
And its Done...Happy Coding with C#
In .Net through version 4 this can be done the same way as for SQL Server Stored Procs but note that you need:
using System.Data.OracleClient;
There are some system requirements here that you should verify are OK in your scenario.
Microsoft is deprecating this namespace as of .Net 4 so third-party providers will be needed in the future. With this in mind, you may be better off using Oracle Data Provider for .Net (ODP.NET) from the word go - this has optimizations that are not in the Microsoft classes. There are other third-party options, but Oracle has a strong vested interest in keeping .Net developers on board so theirs should be good.
Instead of
cmd = new OracleCommand("ProcName", con);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("ParName", OracleDbType.Varchar2, ParameterDirection.Input).Value = "foo";
You can also use this syntax:
cmd = new OracleCommand("BEGIN ProcName(:p0); END;", con);
cmd.CommandType = CommandType.Text;
cmd.Parameters.Add("ParName", OracleDbType.Varchar2, ParameterDirection.Input).Value = "foo";
Note, if you set cmd.BindByName = False (which is the default) then you have to add the parameters in the same order as they are written in your command string, the actual names are not relevant. For cmd.BindByName = True the parameter names have to match, the order does not matter.
In case of a function call the command string would be like this:
cmd = new OracleCommand("BEGIN :ret := ProcName(:ParName); END;", con);
cmd.CommandType = CommandType.Text;
cmd.Parameters.Add("ret", OracleDbType.RefCursor, ParameterDirection.ReturnValue);
cmd.Parameters.Add("ParName", OracleDbType.Varchar2, ParameterDirection.Input).Value = "foo";
// cmd.ExecuteNonQuery(); is not needed, otherwise the function is executed twice!
var da = new OracleDataAdapter(cmd);
da.Fill(dt);
Below worked for me in .NET Core solution. Note that it uses OracleDataReader and Oracle CommandType is CommandType.Text
using Oracle.ManagedDataAccess.Client;
.......
string spSql = "BEGIN STORED_PROC_NAME(:IN_PARAM, :OUT_PARAM1, :OUT_PARAM2); END; ";
using (OracleConnection oraCnn = new OracleConnection(cnnString))
using (OracleCommand oraCommand = new OracleCommand(spSql, oraCnn))
{
await oraCnn.OpenAsync(cancellationToken);
oraCommand.CommandType = CommandType.Text;
oraCommand.BindByName = true;
oraCommand.Parameters.Add("IN_PARAM", OracleDbType.Long, ParameterDirection.Input).Value = 123;
oraCommand.Parameters.Add("OUT_PARAM1", OracleDbType.Int32, null, ParameterDirection.Output);
oraCommand.Parameters.Add("OUT_PARAM2", OracleDbType.Varchar2, 4000, null, ParameterDirection.Output);
OracleDataReader objReader = oraCommand.ExecuteReader();
string outParamValue= oraCommand.Parameters["OUT_PARAM2"].Value.ToString();
}

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