Today i'm working on a project where I will create a relational database through source code and not through the built-in wizard.I have been looking for tutorials which explain to me the processes of doing this but seem to not be able to do so. Most have tutorials on how to use the build-in wizard and add content to tables, my main goal is to actually have a utility that users could use which includes a self-building database. if you have examples of this, I would greatly appreciate it or if you know of any good tutorials that will be helpful too
Thanks!
class Program
{
static string strcon = #"user id = sde ; password = passrd;
server =dfgserver;database =valrollclients";
static SqlCommand cmdinserted = new SqlCommand();
static SqlConnection con; //declaring a connection object
static void Main(string[] args)
{
cmdinserted.CommandText = "[dbo].[prcinsert_client]";
cmdinserted.CommandTimeout = 0;
cmdinserted.CommandType = CommandType.StoredProcedure;
cmdinserted.Connection = con;
cmdinserted.Parameters.Add("#client_name",
SqlDbType.VarChar, 12).Value = "me";
cmdinserted.Parameters.Add("#client_lastname",
SqlDbType.VarChar, 15).Value = "abutair";
cmdinserted.Parameters.Add("#client_age ",
SqlDbType.Int, 4).Value = 4;
try
{
con.Open(); //open connection
cmdinserted.ExecuteNonQuery(); //execute the stored procedure
con.Close();//close connection
}
catch (SqlException) //catch an error
{
throw; //throw it back to the calling method
}
This is the code you have to run on the server:
USE master;
GO
CREATE DATABASE Sales
ON
( NAME = Sales_dat,
FILENAME = 'C:\Program Files\Microsoft SQL Server\MSSQL11.MSSQLSERVER\MSSQL \DATA\saledat.mdf',
SIZE = 10,
MAXSIZE = 50,
FILEGROWTH = 5 )
LOG ON
( NAME = Sales_log,
FILENAME = 'C:\Program Files\Microsoft SQL Server\MSSQL11.MSSQLSERVER\MSSQL\DATA\salelog.ldf',
SIZE = 5MB,
MAXSIZE = 25MB,
FILEGROWTH = 5MB ) ;
GO
You can add it into a SqlCommand. You will need an SqlConnection which I see you have.
Hope it helps.
It seems like this is being made way more complicated than it needs to be if you're planning to use SQL server.
Your application offers the user a way to enter a SQL server instance location and user with admin rights.
You then have a class with various methods which create your database, create your tables etc.
So you would do:
1) If not exists create database X.
2) IF not exists create tables A B C etc
3) alter the tables to setup the relations
4) If not exists create stored proc spA spB etc etc
and just build up the database that way.
Each step above would be a separate method which executes some inline SQL.
If you write the SQL to always check if the thing you're going to create exists it can be used to upgrade as well as create.
Related
I am developing an asp.net web application and I am trying to add a user xp system to it. I have a SQL Server database connected to it and I am trying to make a function that will give 5 experience points to the user.
I queried to the user that is logged in, accessed the user_xp column, and I am trying to add +5 to the old session variable for xp, then send that back into the database to be stored. Here is my code, I am not sure what is wrong with it.
void generateXp()
{
try
{
SqlConnection con = new SqlConnection(strcon);
if (con.State == ConnectionState.Closed)
{
con.Open();
}
SqlCommand cmd = new SqlCommand("UPDATE member_master_tbl SET user_xp = #user_xp WHERE " +
"user_name = '" + Session["username"].ToString().Trim() + "'", con);
int xp = 5;
int current_xp = Convert.ToInt32(Session["user_xp"]);
int new_xp = xp + current_xp;
string new_xp2 = Convert.ToString(new_xp);
cmd.Parameters.AddWithValue("user_xp", new_xp2);
}
catch (Exception ex)
{
}
}
Try renaming the SQL parameter to #user_xp.
cmd.Parameters.AddWithValue("#user_xp", new_xp2);
I don't have an accessible database to test. Also, you need to add the command to execute the query at the end.
cmd.ExecuteNonQuery()
That being said, it's a good practice to learn to separate DB queries to stored procedures or functions.
As others noted, you simply forgot to do a execute non query to run the command that you setup.
However, you can write things this way. You don't mention or note what the data type the experience points column is - I assumed "int".
So, your code block can be written this way:
using (SqlCommand cmd = new SqlCommand("UPDATE member_master_tbl SET user_xp = #user_xp WHERE user_name = #user",
new SqlConnection(strcon)))
{
cmd.Parameters.Add("#user_xp", SqlDbType.Int).Value = 5 + Session("user_xp");
cmd.Parameters.Add("#user", SqlDbType.NVarChar).Value = Session("username");
cmd.Connection.Open();
cmd.ExecuteNonQuery();
}
note how the command object has a connection object (so we don't need a separate one).
And while several people here "lamented" the string concentration to build the sql and warned about sql injection?
Actually, the introduction of # parameters for both values cleans up the code. So you get nice parameters - nice type checking, and you don't have to remember to add/use/have things like quotes around teh string, but not for numbers.
And I let .net cast the number expression from session() - this also likely is ok.
Also the "using block" also correctly cleans up the command object and also the connection object - so the using block is a good idea here.
I wrote the following code for connecting to an oracle database with my c# code:
private string GenerateConnectionString()
{
return "Data Source=( DESCRIPTION = ( ADDRESS_LIST = ( ADDRESS = ( PROTOCOL = TCP )( HOST = 192.168.X.XXX)( PORT = 1521 ) ) )( CONNECT_DATA = ( SERVER = DEDICATED )( SERVICE_NAME = XXXX ) ) ); User Id= xxxxxx; Password = xxxxxx;";
}
private void button1_Click_1(object sender, EventArgs e)
{
try
{
using (OracleConnection connection = new OracleConnection(GenerateConnectionString()))
{
connection.Open();
lblState.Text = connection.State.ToString();
OracleCommand oc = connection.CreateCommand();
oc.CommandText = "INSERT INTO TABLE (NO1, NO2, NO3, NO4, NO5, NO6, NO7, NO8, NO9, NO10, NO11, NO12, DATE) VALUES(1,2,3,1,1,1,'{txb_Textbox1.Text}',5,0.5,10,11,12,TO_DATE('09.07.2020 16:24:00', 'DD.MM.YYYY HH24:MI:SS'))";
oc.ExecuteNonQuery();
}
}
catch (Exception ex)
{
MessageBox.Show( "Exception: " + ex.Message );
lblState.Text = ex.Message;
}
}
I also installed all the necessary drivers for connecting to the oracle database and added the System.Data.OracleClient.dll as a reference to my c# project and added the "oraocci19.dll" and "oraocci19d.dll" file to the project file. I also added the oracle client to the system environment variables under PATH. Furthermore, I declared using System.Data.OracleClient;at the beginning of my overall code.
Please don't tell me that I do not use the latest Oracle Data Access Components (ODACs). I know that. We have a very old Oracle Database and I like the idea that I only need to install a few oracle dll's for it to work.
I just don't know what to do and spent the whole Friday and the whole weekend researching so that I could write to the Oracle database. I hope that someone experienced recognizes the problem directly and can help me.
Thank you very much in advance! :) Best regards
Edit1: Maybe I should try the other Oracle Data Access Components (ODACs) and their dlls. But normally my dll files should also work. A colleague of mine used my ODAC Installation and he said everything worked with it. But, he only had to read data from an Oracle table and not write in one.
Edit2: I got the problem! I was able to find the solution. Their was a mistake in my Oracle Prompt in the string. The C# code was correct. Here on stackoverflow I have of course reformulated and generalized the Oracle prompt string because it contains trusted data. The error was in the Oracle Command. This thread can be closed. Pete -S- got the right answer!
You could try this:
//Do the insert
oc.CommandText = "INSERT INTO TABLE (NO1, NO2, NO3, NO4, NO5, NO6, NO7, NO8, NO9, NO10, NO11, NO12, DATE) VALUES(1,2,3,1,1,1,'{txb_Textbox1}',5,0.5,10,11,12,TO_DATE('09.07.2020 16:24:00', 'DD.MM.YYYY HH24:MI:SS'))";
oc.ExecuteNonQuery;
//Retrieve in a separate action (you have to update your command to SELECT from INSERT)
oc.CommandText = "SELECT * FROM TABLE"; Statement
OracleDataReader reader = oc.ExecuteReader();
Another thing you can look at, is the CommandBuilder; but, it's the easy way out then a good solution. You can then specify the SELECT and the command builder will create the INSERT, UPDATE and DELETE commands.
Other thoughts
I don't think you can bind a data reader to a .DataSource. You can load a data table from a data reader, see this example.
Here is more information on DataAdapters and DataReaders
To UPDATE/INSERT: use .ExecuteNonQuery
To SELECT: there are different options, one is to build a DataTable via DataAdapaters and bind the data source using the data table.
You are doing it in the wrong order, you need to set the command text first and then execute the command (with ExecuteNonQuery() or ExecuteReader()):
OracleCommand oc = connection.CreateCommand();
oc.CommandText = "INSERT INTO TABLE (NO1, NO2, NO3, NO4, NO5, NO6, NO7, NO8, NO9, NO10, NO11, NO12, DATE) VALUES(1,2,3,1,1,1,'{txb_Textbox1}',5,0.5,10,11,12,TO_DATE('09.07.2020 16:24:00', 'DD.MM.YYYY HH24:MI:SS'))";
OracleDataReader reader = oc.ExecuteReader();
I want to insert values in "Navn" row and "Varenr" row in the DB table, when I'm clicking on a button. I have following code:
private void button2_Click(object sender, EventArgs e)
{
using (SqlConnection cn = new SqlConnection(#"Data Source=(LocalDB)\v11.0;AttachDbFilename=|DataDirectory|\Produkt.mdf;Integrated Security=True"))
{
try
{
SqlCommand cm = new SqlCommand();
cm.Connection = cn;
string col1 = textBox2.Text;
string col2 = textBox3.Text;
//generate sql statement
cm.CommandText = "INSERT INTO ProduktTable (Navn,Varenr) VALUES (#col1,#col2)";
//add some SqlParameters
SqlParameter sp_add_col1 = new SqlParameter();
sp_add_col1.ParameterName = "#col1";
//data type in sqlserver
sp_add_col1.SqlDbType = SqlDbType.NVarChar;
//if your data type is not number,this property must set
//sp_add_col1.Size = 20;
sp_add_col1.Value = textBox2.Text;
//add parameter into collections
cm.Parameters.Add(sp_add_col1);
//in your insert into statement, there are how many parameter, you must write the number of parameter
SqlParameter sp_add_col2 = new SqlParameter();
sp_add_col2.ParameterName = "#col2";
//data type in sqlserver
sp_add_col2.SqlDbType = SqlDbType.NVarChar;
//if your data type is not number,this property must set
//sp_add_col2.Size = 20;
sp_add_col2.Value = textBox2.Text;
//add parameter into collections
cm.Parameters.Add(sp_add_col2);
//open the DB to execute sql
cn.Open();
cm.ExecuteNonQuery();
cn.Close();
}
catch (Exception ex)
{
MessageBox.Show("Error\n" + ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
}
But unfortunately, my data table is still empty:
I have set a breakpoint on the ExecuteNonQuery function, and it is triggered, when pressing on the button:
My table definition:
Your connection string is causing this:
Data Source=(LocalDB)\v11.0;AttachDbFilename=|DataDirectory|\Produkt.mdf;Integrated Security=True"
|DataDirectory| Your database that is being updated in this method is in your App Data Directory while the one you are trying to retrieve data from is in your project folder...
|DataDirectory| is a substitution string that indicates the path to the database. DataDirectory also makes it easy to share a project and also to deploy an application. For my PC my App Data Directory is:
C:\Users\MyUserName\AppData\...
If you browse to this location and then go to following folders
...\Local\Apps\2.0\Data
You will be able to find your particular application directory probably stored with your assembly name, or some hash when you go there you will find it the database there is being updated just fine. This connection string is best for deployment.
You can also try this:
If you notice that Server Explorer is detecting all the databases on my PC and you can notice that there are couple of MINDMUSCLE.MDF files but all are at different paths, this is because there is one file in DEBUG directory, one in my PROJECT directory, one in my APP DATA directory. The ones starting with the numbers are stored in my APP DATA directories... If you select your respective database file and then run the SELECT query against it, you will get your data.
I made a tutorial some time ago. May be it will help you:
Check the value that ExecuteNonQuery is returning. It should return an int with the number of records affected by the SQL statement.
If it comes back with a value other than 0, then you know a record is being inserted somewhere. Before you close the connection, run a SQL query against the table to select all of the records and see if they come back through the code.
SELECT * FROM ProduktTable
If you get some records, then you may want to double check the database you're looking at through the IDE and the one your inserting records into through the code. It could be possible that you've got two different databases and you're querying one while inserting into another one.
Those are the steps that I would go through to help narrow down the issue and sounds like something I've probably done before. I hope it helps!
Whenever I run the following code I get the expected output
private int NewBorrower(string givenName, string surname)
{
int returnValue = 0;
using (conn)
{
conn.Open();
string sql = "AddBorrower";
cmd = new SqlCommand(sql, conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("#givenName", SqlDbType.NVarChar).Value = givenName;
cmd.Parameters.Add("#surname", SqlDbType.NVarChar).Value = surname;
SqlParameter id = cmd.Parameters.Add("#id", SqlDbType.Int);
id.Direction = ParameterDirection.ReturnValue;
try
{
cmd.ExecuteNonQuery();
returnValue = (int)cmd.Parameters["#id"].Value;
}
catch (Exception e)
{
Console.WriteLine("Commit Exception Type: {0}", e.GetType());
Console.WriteLine(" Message: {0}", e.Message);
}
}
return returnValue;
}
When run from the front end I get the results I want, but when I check the database it doesn't show up in the table.
For good measure this is also the stored procedure being used
CREATE PROCEDURE [dbo].[AddBorrower]
#givenName nvarchar(50),
#surname nvarchar(50),
#id int = NULL OUTPUT
AS
INSERT INTO llBorrowers (givenName, surname)
VALUES (#givenName, #surname);
SET #id = SCOPE_IDENTITY();
RETURN #id
I've tried using transactions on both the c# and sql sides, and that didn't work at all.
I should also mention that it is a local database, but I'm not sure that should affect it.
When you use the DataDirectory substitution string in a WinForms application, its real value changes depending on your debug or release configuration.
In DEBUG your DataDirectory points to PROJECTFOLDER\BIN\DEBUG (or x86 variation if it is the case).
So it is extremely easy to get fooled by this. You create a connection in server explorer but this connection is ignored by your code that works on a different database.
You could create another connection in Server Explorer and name it DebugConnection, still keeping the original one for schema changes while you use the DebugConnection to check if your code executes as expected
As a side note, keep particular attention to the property Copy To the Output Directory property on the MDF file if it is listed between the project items. If you set it to Copy Always every time you start a debug session a fresh copy of your db will be copied from the project directory to the output directory effectively destroying the updates executed by your code. I recommend to set it to Copy Never and handle manually the database schema changes
A reference: Where is DataDirectory
You may try creating a SQLTransaction in C# part
Also, try changing your code like -
//Just create a SQL connection - cmd = new SqlCommand(conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.CommandText = "AddBorrower";
Background:
I am using sql statements to create a Temp database on a server which will store data until it is needed further by my client program.
Problem:
My sql statement to create the database works properly and creates the database with all the required specifications when run through Sql Management studio, on the other hand when my program executes the statement it only creates a database with the 'Default' settings except for the name.
Questions:
Why is this?
How can I make it create a database with my specifications
Sql statement:
CREATE DATABASE Temp ON PRIMARY(
NAME = Temp
, FILENAME = 'C:\Temp.mdf'
, SIZE = 2MB
, FILEGROWTH = 10%) LOG ON (
NAME = Temp_Log
, FILENAME = 'C:\Temp.ldf'
, SIZE = 1MB, MAXSIZE = 70MB
, FILEGROWTH = 10%)
Code:
public void AcuConvert()
{
using (DestD)
{
SqlCommand command = new SqlCommand();
DestD.Open();
command.Connection = DestD;
foreach (var item in Entity.SqlDestinationQueries.ToList())
{
command.CommandText = item.Query;
command.ExecuteNonQuery(); //This is where the command is run
}
foreach (var item in Entity.SystemQueries.ToList())
{
command.CommandText = item.Query.Replace("#Sys", SysD.Database);
command.ExecuteNonQuery();
}
foreach (var item in Entity.InsertQueries.ToList())
{
command.CommandText = item.Query.Replace("#Source", SourceD.Database); ;
command.ExecuteNonQuery();
}
}
}
Have you tried using SQL Server Management Objects instead of a raw SQL statement?
For example:
using Microsoft.SqlServer.Management.Smo;
using Microsoft.SqlServer.Management.Common;
...
// Connect to the default instance
Server server = new Server();
// Establish new database details
Database database = new Database(server, "MyTempDB");
// Add primary filegroup details
database.FileGroups.Add(new FileGroup(database, "PRIMARY"));
// Set Primary datafile properties
DataFile primaryFile = new DataFile(database.FileGroups["PRIMARY"],
"MyTempDB_Data", "C:\\MyTempDB.mdf");
primaryFile.Size = 2048; // Sizes are in KB
primaryFile.GrowthType = FileGrowthType.Percent;
primaryFile.Growth = 10;
// Add to the Primary filegroup
database.FileGroups["PRIMARY"].Files.Add(primaryFile);
// Define the log file
LogFile logfile = new LogFile(database, "MyTempDB_Log", "C:\\MyTempDB_Log.ldf");
logfile.Size = 1024;
logfile.GrowthType = FileGrowthType.Percent;
logfile.Growth = 10;
logfile.MaxSize = 70 * 1024;
// Add to the database
database.LogFiles.Add(logfile);
// Create
database.Create();
database.Refresh();
You can connect to the server with specific credentials, too, of course:
http://msdn.microsoft.com/en-us/library/microsoft.sqlserver.management.smo.server.aspx
If, however, you're stuck with using text scripts to create your database, I'd ensure that your Initial Catalog is set correctly (i.e. to 'master') in your connection string and your user has the necessary permissions - CREATE DATABASE / CREATE ANY DATABASE / ALTER DATABASE. If this still doesn't give you any joy, try stripping out the rest of your C# code and run the create SQL independently of the other statements - it could be that there's a side-effect from a preceding query. Use Profiler to see exactly what's running as you add them back in.
Edit:
I tested your script against a local SQL Server instance (2012 SqlLocalDB) via a small C# program using SqlClient and it ran just fine after changing the file paths to ones I had write access to (root of C is protected by default). The only other amendment was that the Primary size had to start at 3MB or more. Any smaller and the default tables could not be created. This may be another avenue of investigation for you to explore.
Your alternative option could be to use the Process class to run the sqlcmd.exe
Eg.
var process = Process.Start(WORKING_PATH, argument);
%WORKING_PATH% being "C:\tools\sql\sqlcmd.exe"
%argument% being "C:\scripts\Create.sql"
I use this strategy to dump test data into test environments when bootstrapping acceptance test fixtures.
Cheers