How to execute a update statement using Oracle ODP.Net in C# - c#

I am using Oracle.DataAccess.Client to work with Oracle database in my ASP.Net application. There is no help documentation in MSDN for ODP.Net and Oracle's documentation is really really bad. I am not able find the answer to this simple question.
Is it not possible to execute a simple update statement without having to build a dataset object and updating the dataset?
How to execute an update statement using Oracle ODP.Net in C#?

I will need to check the exact syntax, but here is some quick code off the top of my head
using (OracleConnection con = new OracleConnection(...))
{
con.Open();
OracleCommand cmd = con.CreateCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText = "update table set col1 = :param1, col2 = :param2 where key = :keyValue";
cmd.Parameters.AddWithValue("param1", 1);
cmd.Parameters.AddWithValue("param2", "Text data");
cmd.Parameters.AddWithValue("keyValue", "1");
cmd.ExecuteNonQuery();
}
The above creates a command object sets the command up to execute an SQL Update statement, in this example I show one way to setup a parameterized query, you should always go with a parameterized query. Once the command is setup you just call ExecuteNonQuery to actually execute the command.

So after a bit of sleuthing and working this one out for a while, I found that the method I used to add a new parameter to the connection command is as follows. I did not find the method as was stated in the previous post. Mind you I am using a query object that I am passing the values around with.
public Boolean InsertMethod(Query _query)
{
var success = false;
var queryString = string.Format(#"INSERT INTO TABLE(ID, OWNER, TEXT) VALUES (TABLE_SEQ.NEXTVAL,:OWNER, :TEXT)");
try
{
using (OracleConnection con = new OracleConnection(ConString))
{
con.Open();
OracleCommand cmd = con.CreateCommand();
cmd.CommandText = queryString;
cmd.Parameters.Add("OWNER", _query.Owner);
cmd.Parameters.Add("TEXT", _query.Text);
int rowsUpdated = cmd.ExecuteNonQuery();
if (rowsUpdated > 0) success = true;
}
return success;
}
catch (Exception ex)
{
log.Error(ex);
throw;
}
}

Further to #Chris's answer, here is the documentation page of OracleParameter class which has sample code on using OracleCommand to execute Updates.
EDIT: Here is the entry point for ODP.net documentation.

Related

How to insert data into local database using C#

I am working on my first project using local database on C#. I have searched on internet different code for inserting data, but nothing has worked for me. I am trying different code, the problem that occurs to me is the built in functions they are using doesn't show up in my code. Can someone share the authentic code for inserting, retrieving and deleting in local database ?
The recent code that I have tried, some exception is occurring in SqlCeConnection.
This is my code :
string str="Data Source=(localdb)shop_database;Initial Catalog=shop_database;Integrated Security=True";
SqlCeConnection con = new SqlCeConnection(str);
SqlCeDataAdapter sda = new SqlCeDataAdapter();
SqlCeCommand cmd = con.CreateCommand();
cmd.CommandText = "Insert into Account_details (Account_No,Customer_name,Customer_father_name,Profession,Mobile_No,Office_Address,House_Address,CNIC,Item_name,Item_color,Item_model,Item_engine_NO,Item_chasis_NO,Cash_price,Installment_price,Advance_given,Amount_left,Monthly_Installment,Monthly_Rent,Date_of_giving,Sponsor_name,Sponsor_father_name,Sponsor_profession,Sponsor_Address,Sponsor_CNIC,Sponsor_Mobile_No) values (#Account_No,#Customer_name,#Customer_father_name,#Profession,#Mobile_No,#Office_Address,#House_Address,#CNIC,#Item_name,#Item_color,#Item_model,#Item_engine_NO,#Item_chasis_NO,#Cash_price,#Installment_price,#Advance_given,#Amount_left,#Monthly_Installment,#Monthly_Rent,#Date_of_giving,#Sponsor_name,#Sponsor_father_name,#Sponsor_profession,#Sponsor_Address,#Sponsor_CNIC,#Sponsor_Mobile_No)";
cmd.Parameters.AddWithValue("#Account_No", this.Textbox0.Text);
cmd.Parameters.AddWithValue("#Customer_name", this.Textbox1.Text);
cmd.Parameters.AddWithValue("#Customer_father_name", this.Textbox2.Text);
cmd.Parameters.AddWithValue("#Profession", this.Textbox3.Text);
cmd.Parameters.AddWithValue("#Mobile_No", this.Textbox4.Text);
cmd.Parameters.AddWithValue("#Office_Address", this.Textbox5.Text);
cmd.Parameters.AddWithValue("#House_Address", this.Textbox6.Text);
cmd.Parameters.AddWithValue("#CNIC", this.Textbox7.Text);
cmd.Parameters.AddWithValue("#Item_name", this.Textbox14.Text);
cmd.Parameters.AddWithValue("#Item_color", this.Textbox15.Text);
cmd.Parameters.AddWithValue("#Item_model", this.Textbox16.Text);
cmd.Parameters.AddWithValue("#Item_engine_NO", this.Textbox17.Text);
cmd.Parameters.AddWithValue("#Item_chasis_NO", this.Textbox18.Text);
cmd.Parameters.AddWithValue("#Cash_price", this.Textbox19.Text);
cmd.Parameters.AddWithValue("#Installment_price", this.Textbox20.Text);
cmd.Parameters.AddWithValue("#Advance_given", this.Textbox21.Text);
cmd.Parameters.AddWithValue("#Amount_left", this.Textbox25.Text);
cmd.Parameters.AddWithValue("#Monthly_Installment", this.Textbox22.Text);
cmd.Parameters.AddWithValue("#Monthly_Rent", this.Textbox23.Text);
cmd.Parameters.AddWithValue("#Date_of_giving", this.Textbox24.Text);
cmd.Parameters.AddWithValue("#Sponsor_name", this.Textbox8.Text);
cmd.Parameters.AddWithValue("#Sponsor_father_name", this.Textbox9.Text);
cmd.Parameters.AddWithValue("#Sponsor_profession", this.Textbox10.Text);
cmd.Parameters.AddWithValue("#Sponsor_Address", this.Textbox11.Text);
cmd.Parameters.AddWithValue("#Sponsor_CNIC", this.Textbox12.Text);
cmd.Parameters.AddWithValue("#Sponsor_Mobile_No", this.Textbox13.Text);
try
{
cmd.ExecuteNonQuery();
MessageBox.Show("Successfully saved");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
To edit, insert, in general interact with your database you need the class SqlCommand. First you create a connection to your database with an SqlConnection object. Then you pass the SQL statement as a string and the connection into the constructor of the SqlConnection class. Little example:
SqlConnection con = new SqlConnection("server=localhost;database=test_db;uid=root;password=yourpassword");
SqlCommand cmd = new SqlCommand("select * from your_table", con);
To retreive the data from the database you need to use the SQL Statements. For example an SQL statement is something like:
insert into my_table (value1, value2)
values("Example", "Insertion");
When you created your SqlConnection and the SqlCommand you need to open the database connection and execute the command. Wether it's a command for receiving information from the database or editing the database you use ExecuteReader() or ExecuteNonQuery(). For example when you want to receive all the Information stored in one table you use:
SqlConnection con = new SqlConnection("connection string as shown above");
SqlCommand cmd = new SqlCommand("select * from example_table", con);
con.Open();
SqlDataReader reader = cmd.ExecuteReader();
while(reader.Read())
Console.WriteLine(reader[<table_index or attribute Name>]);
And finally dont forget to call the close method on your SqlConnection and SqlDataReader object
You are probably making two mistakes:
Problem 1. Your connecting string looks like wrong. Instead of:
Data Source=(localdb)shop_database;Initial Catalog=shop_database;Integrated Security=True";
It should be:
Data Source=(LocalDb)\MSSQLLocalDB;Initial Catalog=shop_database;Integrated Security=True";
Problem 2. You are not opening the connection before executing the command. Your code in the block should be like this:
try
{
conn.Open(); // Open the connection
cmd.ExecuteNonQuery();
MessageBox.Show("Successfully saved");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
finally
{
conn.Close(); // Close the connection
}
As a best practice, I recommend that you use "using" block to create your connection. In that case, you don't have to explicitly close the connection and set it to null:
try
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
conn.Open();
// Remaining code
}
}
catch(Exception ex)
{
// Manage your exception here
}

Running a t-sql stored procedure with EXECUTE AS statement with .NET SqlCommand

I have a .NET web service application that executes parameterized MS SQL Server stored procedures using System.Data.SqlCommand. The application receives a name of the stored procedure and its parameters from user input.
Also the application deployed within Windows AD domain and it is able to obtain the name of a remote user with the help of SSPI authentication.
using (var con = new SqlConnection(connectionString)) {
using (var cmd = new SqlCommand(procedureName, con)) {
cmd.CommandType = CommandType.StoredProcedure;
foreach (var pair in pairs.AllKeys) {
cmd.Parameters.Add(new SqlParameter(pair, pairs[pair]));
}
con.Open();
using (var reader = cmd.ExecuteReader()) {
// processing results
}
}
}
Now I want to execute a stored procedure with an EXECUTE AS statement.
use [db]
go
execute as user = 'domain\user' --execute as RemoteUser
exec [db].[stored_procdure] #param1=value1
Can this be done? How can I add EXECUTE AS to the SqlCommand?
I would not like to resort to sql injection prone code and build the sql request from strings received from user.
Solved it some time ago with a colleague of mine.
To achieve the requested behavior the execute as statement should be run in a separate preceeding SqlCommand while in the same SqlConnection.
After the closing of the reader, still in the same SqlConnection, there's another separate SqlCommand needed - revert - to switch back the context.
I was having a similar issue where I was able to Execute as User but the Revert wasn't working. By following prot's answer I was able to fix it. So for anyone having a similar issue this is how the code looks
SqlCommand cmd = new SqlCommand("EXECUTE AS USER = 'domain\\user';");
OSSDBDataContext dc = new OSSDBDataContext();
cmd.Connection = dc.Connection as SqlConnection;
cmd.Connection.Open();
cmd.ExecuteNonQuery();
//Execute stored procedure code goes here
SqlCommand cmd2 = new SqlCommand("REVERT;");
cmd2.Connection = dc.Connection as SqlConnection;
cmd2.ExecuteNonQuery();

SQL Update statement doesn't update values when adding multiple columns otherwise it does

No exceptions, everything gets executed but the update doesn't happen!
Everything works ok when I have just #JIR parameter but now I added #Paragon and the update doesn't do it's job. No exception whatsoever data passed is OK...
I don't see anything wrong with this query does anyone know what could possibly be going wrong?
private static void InsertJIR(FisDnevni racun)
{
using (OleDbConnection con = new OleDbConnection(RegistarBlagajna.Modul.VezaNaBazu.ConnectionString))
{
try
{
con.Open();
OleDbCommand cmd = new OleDbCommand(#"
UPDATE FisDnevni
SET [JIR] = #JIR,
[Paragon] = #Paragon
WHERE BrojRacuna = #BrojRacuna"
, con);
cmd.Parameters.AddWithValue("#JIR", racun.JIR.Substring(0,37));
cmd.Parameters.AddWithValue("#BrojRacuna", racun.BrojRacuna);
cmd.Parameters.AddWithValue("#Paragon", racun.Paragon);
cmd.ExecuteNonQuery();
con.Close();
}
catch (Exception)
{
throw;
}
}
}
This is a good old problem - ensure the query parameters in OleDbParameter are declared in proper order like this:
using (OleDbConnection con = new OleDbConnection(RegistarBlagajna.Modul.VezaNaBazu.ConnectionString))
{
try
{
con.Open();
using (OleDbCommand cmd = new OleDbCommand(#"UPDATE FisDnevni SET [JIR] = #JIR, [Paragon] = #Paragon WHERE BrojRacuna = #BrojRacuna", con)
{
cmd.Parameters.AddWithValue("#JIR", racun.JIR.Substring(0,37));
// this must be the second parameter instead of third one
cmd.Parameters.AddWithValue("#Paragon", racun.Paragon);
cmd.Parameters.AddWithValue("#BrojRacuna", racun.BrojRacuna);
cmd.ExecuteNonQuery();
con.Close();
}
}
catch (Exception)
{
throw;
}
}
Note that OLE DB .NET Provider doesn't recognize named parameters for OleDbCommand when CommandType is set to Text, but it apparently does recognize the parameter order, hence as long as they're passed in proper order, it'll accepted as query parameter.
Related issue:
how to update a table using oledb parameters?
maybe i've just never used it, but why is there an # here?
OleDbCommand(#"
i also havent worked with C# in a while but is multi-line concatenation possible without a + or something?
thirdly why are you using [] on these column names? i don't see any special characters or spaces.
this post is sounding a lot more dikkish than i mean it to be, im not trying, just legit curious

Execute any Raw SQL Query

IS it possible to execute a raw SQL command of any type (SELECT, UPDATE, DELETE....) in C#. I am looking to add a feature similar to the SQL Server Management Studio query window where I can just type in any SQL command and it executes it. In my case I am not worried about sql injection, I know this risk with this feature. All the connection parameters are passed to me (I have a valid connection string), but I know nothing about the database itself. The SQL command is also syntactically correct before I get the command. I cannot seem to find a solution that will work in all cases, probably just overlooking the obvious solution.
Here is an ADO example for you
using System;
using System.Data;
using System.Data.SqlClient;
class Program
{
static void Main()
{
string connectionString =
"Data Source=(local);Initial Catalog=Northwind;"
+ "Integrated Security=true";
// Provide the query string with a parameter placeholder.
string queryString =
"UPDATE [dbo].[USR_Users] SET [Active] = 1 WHERE Id = 1";
using (SqlConnection connection =
new SqlConnection(connectionString))
{
SqlCommand command = new SqlCommand(queryString, connection);
try
{
connection.Open();
command.ExecuteNonQuery();
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
Console.ReadLine();
}
}
You can simply use ADO .NET and show the results of the query if it executed successfully or not, just put the following code in the event handler when you want to execute your query:
using (SqlConnection conn = ConnectionClass.GetInstance().Connection())
using (SqlCommand cmd = new SqlCommand(TextBoxQuery.Text, conn))
{
conn.Open();
TextBoxNoOfRowEffected.Text = cmd.ExecuteNonQuery().ToString();
}
SqlCommand.ExecuteNonQuery() Documentation

Cannot add data into database in visual c#

As a beginner to c#, and I actaully spent a lot of time researching this:
I cannot add some data into the database, I can extract data from it, but cannot add anything into the database. I use sql server as my database.
try {
fname = fname_tb.Text;// first name
sname = sname_tb.Text; // second name
q = "insert into beforebath1(firstname,secondname) values(#fname,#sname)";
conn_string = Properties.Settings.Default.beforebath_connection_string;
SqlConnection co = new SqlConnection(conn_string);
SqlCommand cmd;
co.Open();
cmd = new SqlCommand(q, co);
cmd.Connection = co;
cmd.Parameters.AddWithValue("#fname", fname_tb.Text);
cmd.Parameters.AddWithValue("#sname", sname_tb.Text);
cmd.ExecuteNonQuery();
co.Close();
}
catch(Exception err) {
MessageBox.Show(err.toString());
}
my sql connection string is this:
Data Source=(LocalDB)\v11.0;AttachDbFilename=|DataDirectory|\beforebath_db.mdf;Integrated Security=True;Connect Timeout=30
It is automatically generated when I created the database. Please help me insert the text in the two textboxes (fname_tb.Text and sname_tb.Text) into the table called beforebath1 of the database called beforebath_db.mdf.
Is it something to do with my data directory?
I see a couple of mistakes in your code.
First, why catch an exception that will only be shown in a message?
It is often best to let the exception bubble up to have the stack trace in debug. This is not the same if this is production code, which I doubt.
Second, make sure to dispose your objects adequately.
The Using Statement is the most prefered way to work with disposeable items such as a database connection and a command.
using (var cnx = new SqlConnection(connectionString)) {
cnx.Open();
var sql = #"insert into beforebath1 (first_name, second_name)
values (#fname, #lname)";
using (var cmd = new SqlCommand(sql, cnx)) {
cmd.Parameters.AddWithValue("#fname", fname_tb.Text);
cmd.Parameters.AddWithValue("#lname", lname_tb.Text);
try {
int rowsAffected = cmd.ExecuteNonQuery();
if (0 < rowsAffected) MessageBox.Show("Success!");
else MessageBox.Show("Failed!");
} catch (SqlException ex) {
// It is almost prefered to let the exception be thrown freely
// so that you may have its full stack trace and have more
// details on your error.
MessageBox.Show(ex.Message);
} finally {
if (cnx.State == ConnectionState.Open) cnx.Close();
}
}
}
This way, wrapping your disposable objects within using blocks, you make sure that everything is getting to get disposed automatically when exiting the code block.
As for your "it doesn't work" problem, I guess the problem be either at the connection string level, or at your table_name level.
You wish to insert into beforebath1, and your insert statement states table_name. Make sure you put the right table name where it belongs so that it may work properly.
Can you change you connection string to this:
Server=(LocalDB)\v11.0;Database=beforebath_db;Trusted_Connection=True;
This means the your app and other programs using the Db will all share the same instance.
Also, as mentioned by #Will, you should wrap your SQLConnection in a using statement for garbage collection.
For better implementations you can use stored_procedures like bellow:
Step1: Declare Stored Procedure for your Query:
CREATE PROCEDURE [dbo].[ADD_TO_BEFORE_PATH_SP]
/*Type of this variables should be their column types*/
#fname varchar(MAX),
#lname varchar(MAX)
AS
BEGIN
INSERT INTO [dbo].[beforebath1] (fname, lname)
VALUES (#fname,#lname)
END
Step2: Using Stored Procedure where you need:
SqlConnection con = new SqlConnection(connectionString);
SqlCommand com = new SqlCommand("ADD_TO_BEFORE_PATH_SP", con);
com.Parameters.AddWithValue("#fname", fname_tb.Text);
com.Parameters.AddWithValue("#lname", lname_tb.Text);
com.CommandType = CommandType.StoredProcedure;
try
{
con.Open();
com.ExecuteNonQuery();
}
catch (Exception)
{
throw;
}
finally
{
if (con.State == ConnectionState.Open)
con.Close();
}

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