Develop Reference

How to save only the new rows AND modified rows in datagridview?

I'm trying to save my data from datagridview row to my sql database. My problem is with my current code, it reads and updates all the rows regardless if it has any changes or not. I know this is going to be a problem especially if my table has large amounts of data.
These are what I did with my code so far:
//retrieve data from dbase
public void loadToDGV()
{
DBConn.DBConnect();
SqlDataAdapter sqlDA = new SqlDataAdapter("SELECT * from TableName", DBConnection.conn);
sqlDA.Fill(dataTable);
gridView.DataSource = dataTable;
}
Below is what's in my Save button.
foreach (DataGridViewRow row in gridView.Rows)
{
DBConn.DBConnect();
SqlCommand comm = new SqlCommand();
comm.Connection = DBConnection.conn;
comm = new SqlCommand("SPName", DBConnection.conn);
comm.CommandType = CommandType.StoredProcedure;
comm.Parameters.AddWithValue("#ID", row.Cells["ID"].Value == DBNull.Value ? "" : row.Cells["ID"].Value);
comm.ExecuteNonQuery();
}
I have another sample code where I can only save modified rows
changeTable = dataTable.GetChanges(DataRowState.Modified);
foreach (DataRow row in changeTable.Rows)
{
DBConn.DBConnect();
SqlCommand comm = new SqlCommand();
comm.Connection = DBConnection.conn;
comm = new SqlCommand("SPName", DBConnection.conn);
comm.CommandType = CommandType.StoredProcedure;
comm.Parameters.AddWithValue("#ID", row["ID"].ToString());
comm.ExecuteNonQuery();
}
What I wanted to do is save only BOTH the "New Rows" AND "Modified Rows".
Is there any way to only get newly added/edited rows? and not include all the rows from the gridview?
My Stored Procedure only checks if the ID is existing or not.
IF NOT EXISTS (SELECT 1 FROM TABLE WHERE ID = #ID)
-- INSERT QUERY
ELSE
-- UPDATE QUERY

You should not be using a loop at all, nor even referring to the grid. You obviously have a DataTable already. If you're not already doing so, populate it with a data adapter, bind it to a BindingSource and bind that to the grid. When it's time to save, call EndEdit on the BindingSource call Update on the data adapter and pass the DataTable. That's it, that's all. There's no need to call GetChanges.
Obviously you will have to configure the data adapter appropriately, with an InsertCommand to insert new records and an UpdateCommand to save modified records. I won't go into specifics as you haven't gone into specifics but there are plenty of examples around. You can find my own here.
EDIT:
The short answer to your question is that, if you want both modified and added rows, then specify both Modified and Added rows. The DataRowState enumeration has the Flags attribute, which means that you can create compound values. That would mean that this:
changeTable = dataTable.GetChanges(DataRowState.Modified);
would become this:
changeTable = dataTable.GetChanges(DataRowState.ModifiedData Or RowState.Added);
If you were going to then loop through those rows, you wouldn't create a new command object every iteration. You'd create one command and add the parameters once, then simply set the Value of each parameter in the loop. You would also need to call AcceptChanges on the original DataTable afterwards.
You should do any of that though. As I said, you should use the same data adapter as you used to retrieve the data to save the changes. Normally you'd use different SQL for the InsertCommand and UpdateCommand but, in your case, you can use the same. Just create a single command object with the appropriate parameters and assign it to both the InsertCommand and UpdateCommand properties, then call Update.

Updating SQL table with the contents of a datatable

I am creating an application in WPF using C# where users populate a datagrid and the information is then stored in a DataTable called smb1. The following code works for inserting the data into the SQL database but when I modify the code for updating it does not work. Does anyone know how I can modify my code to allow Updates as there are no errors thrown when I run my application in Visual Studio. I must add that the Equipment column cannot be edited in the datagrid so the returned data is the same as the data taken from the database so that the updated rows will be matched to the equipment rows in the SQL database using the WHERE clause. Below is the original insertion code plus my attempt for updating the database.
Insert Code
SqlConnection con = new SqlConnection(MyConnectionString);
string SqlCmdText = "Insert into SHIFTLOG Values(#EQUIPMENT,#BATCHNO,#PRODUCTNO,#STATUS,#DATE,#PERIOD,#MACHINE)";
SqlCommand sc = new SqlCommand(SqlCmdText, con);
con.Open();
foreach (DataRow row in smb1.Rows)
{
sc.Parameters.Clear();
sc.Parameters.AddWithValue("#EQUIPMENT", row["EQUIPMENT"]);
sc.Parameters.AddWithValue("#BATCHNO", row["BATCHNO"]);
sc.Parameters.AddWithValue("#PRODUCTNO", row["PRODUCTNO"]);
sc.Parameters.AddWithValue("#STATUS", row["STATUS"]);
sc.Parameters.AddWithValue("#DATE", DateTime.Now.ToString("yyyy-MM-dd"));
sc.Parameters.AddWithValue("#PERIOD", DateTime.Now.ToString("tt"));
sc.Parameters.AddWithValue("#MACHINE", "SMB1");
sc.ExecuteNonQuery();
}
con.Close();
Attempt for Update Code
SqlConnection con = new SqlConnection(MyConnectionString);
string SqlCmdText = "UPDATE SHIFTLOG SET EQUIPMENT='#EQUIPMENT',BATCHNO='#BATCHNO',PRODUCTNO='#PRODUCTNO',STATUS='#STATUS',DATE='2013-09-12',PERIOD='#PERIOD',MACHINE='#MACHINE' WHERE EQUIPMENT='#EQUIPMENT'";
SqlCommand sc = new SqlCommand(SqlCmdText, con);
con.Open();
foreach (DataRow row in smb1.Rows)
{
sc.Parameters.Clear();
sc.Parameters.AddWithValue("#EQUIPMENT", row["EQUIPMENT"]);
sc.Parameters.AddWithValue("#BATCHNO", row["BATCHNO"]);
sc.Parameters.AddWithValue("#PRODUCTNO", row["PRODUCTNO"]);
sc.Parameters.AddWithValue("#STATUS", row["STATUS"]);
sc.Parameters.AddWithValue("#PERIOD", DateTime.Now.ToString("tt"));
sc.Parameters.AddWithValue("#MACHINE", row["MACHINE"]);
sc.ExecuteNonQuery();
}
con.Close();
Thanks for any help.

Remove the single quotes around the parameters.
string SqlCmdText = "UPDATE SHIFTLOG SET EQUIPMENT=#EQUIPMENT,BATCHNO=#BATCHNO,PRODUCTNO=#PRODUCTNO,STATUS=#STATUS,DATE='2013-09-12',PERIOD=#PERIOD,MACHINE=#MACHINE WHERE EQUIPMENT=#EQUIPMENT";
Also, I think the update section for EQUIPMENT=#EQUIPMENT is redundant, as the where clause will not be correct if it has changed. So you could use
string SqlCmdText = "UPDATE SHIFTLOG SET BATCHNO=#BATCHNO,PRODUCTNO=#PRODUCTNO,STATUS=#STATUS,DATE='2013-09-12',PERIOD=#PERIOD,MACHINE=#MACHINE WHERE EQUIPMENT=#EQUIPMENT";

remove the '' in all the parameters in your sql statement
"UPDATE SHIFTLOG SET BATCHNO=#BATCHNO,....... WHERE EQUIPMENT=#EQUIPMENT
if you use quotes all your parameters take as string values, not as SQL parameters
And also you need to use columns with [] like [DATE] if those are reserved keywords
How to deal with SQL column names that look like SQL keywords?

Using OleDbDataAdapter to update a DataTable C#

I have been trying to use OleDbDataAdapter to update a DataTable but got confused about the commands.
Since I sometimes get info from diffrent tables I can't use a CommandBuilder.
So I have tried to create the commands on my on but found it hard with the parameters.
DataTable.GetChanges returns rows that needs to use an INSERT or an UPDATE command - I guess I can't distinct between them.
I need you to complete the following:
DataTable dt = new DataTable();
OleDbDataAdapter da = new OleDbDataAdapter();
// Here I create the SELECT command and pass the connection.
da.Fill(dt);
// Here I make changes (INSERT/UPDATE) to the DataTable (by a DataGridView).
da.UpdateCommand = new OleDbCommand("UPDATE TABLE_NAME SET (COL1, COL2, ...) VALUES (#newVal1, #newVal2, ...) WHERE id=#id"); // How can I use the values of the current row (that the da is updating) as the parameters (#newVal1, #newVal2, id....)?
Thank you very much!

The data adapter can work in conjunction with the datatable. As such, I've actually wrapped mine together into a class and works quite well. Aside from the complexities of my stuff, here's a snippet that might help you along. When adding a parameter, you can identify the column source that the data is coming from FROM the DataTable. This way, when a record is internally identified as "Added" or "Updated" (or "Deleted"), when you build your SQL Insert/Update/Delete commands, it will pull the data from the columns from the respective rows.
For example. Say I have a DataTable, primary Key is "MyID" and has columns "ColX, ColY, ColZ". I create my DataAdapter and build out my select, update, delete commands something like... (? is a place-holder for the parameters)
DataAdapter myAdapter = new DataAdapter()
myAdapter.SelectCommand = new OleDbCommand();
myAdapter.InsertCommand = new OleDbCommand();
myAdapter.UpdateCommand = new OleDbCommand();
myAdapter.DeleteCommand = new OleDbCommand();
myAdapter.SelectCommand.CommandText = "select * from MyTable where MyID = ?";
myAdapter.InsertCommand.CommandText = "insert into MyTable ( ColX, ColY, ColZ ) values ( ?, ?, ? )";
myAdapter.UpdateCommand.CommandText = "update MyTable set ColX = ?, ColY = ?, ColZ = ? where MyID = ?";
myAdapter.DeleteCommand.CommandText = "delete from MyTable where MyID = ?";
Now, each has to have their respective "Parameters". The parameters have to be addded in the same sequence as their corresponding "?" place-holders.
// Although I'm putting in bogus values for preparing the parameters, its just for
// data type purposes. It does get changed through the data adapter when it applies the changes
OleDbParameter oParm = new OleDbParameter( "myID", -1 );
oParm.DbType = DbType.Int32;
oParm.SourceColumn = "myID"; // <- this is where it looks back to source table's column
oParm.ParameterName = "myID"; // just for consistency / readability reference
myAdapter.SelectCommand.Parameters.Add( oParm );
do similar for rest of parameters based on their types... char, int, double, whatever
Again, I have like a wrapper class that handles managment on a per-table basis... in brief
public myClassWrapper
{
protected DataTable myTable;
protected DataAdapter myAdapter;
... more ...
protected void SaveChanges()
{
}
}
Its more complex than just this, but during the "SaveChanges", The datatable and dataAdapter are in synch for their own purposes. Now, flushing the data. I check for the status of the table and then you can pass the entire table to the dataAdapter for update and it will cycle through all changed records and push respective changes. You'll have to trap for whatever possible data errors though.
myAdapter.Update( this.MyTable );
As it finds each "changed" record, it pulls the values from the Column Source as identified by the parameter that is found in the table being passed to the adapter for processing.
Hopefully this has given you a huge jump on what you are running into.
---- COMMENT PER FEEDBACK ----
I would put your update within a try/catch, and step into the program to see what the exception is. The message adn/or inner exception of the error might give more info. However, try to simplify your UPDATE to only include a FEW fields with the WHERE "Key" element.
Additionally, and I oopsed, missed this from first part answer. You might have to identify the datatable's "PrimaryKey" column. To do so, its a property of the DataTable that expects and array of columns that represent the primary key for the table. What I did was...
// set the primary key column of the table
DataColumn[] oCols = { myDataTbl.Columns["myID"] };
myDataTbl.PrimaryKey = oCols;
I would comment out your full update string and all its parameters for your UPDATE. Then, build it with just as simple as my sample of only setting 2-3 columns and the where clause
myAdapter.UpdateCommand.CommandText = "update MyTable set ColX = ?, ColY = ? where MyID=?";
Add Parameter object for "X"
Add Parameter object for "Y"
Add Parameter object for "MyID"
Pick fields like int or char so they have the least probability of problems for data type conversions, then, once that works, try adding all your "int" and "character" columns... then add any others. Also, which database are you going against. SOME databases don't use "?" as placeholder in the command but use "named" parameters, some using
"actualColumn = #namedCol"
or even
"actualColumn = :namedCol"
Hope this gets you over the hump...

You could use the String.Format Method to replace the #newVal1, #newVal2, ... in your code, like this da.UpdateCommand = new OleDbCommand(String.Format("UPDATE TABLE_NAME SET (COL1, COL2, ...) VALUES ({0}, {1}, ...) WHERE id=#id",OBJECT_ARRAY_CONTAINING_VALUES_FROM_THEDG));
[Eidt per comment]
To handle the row[0], row[1] you need a loop like:
for(i=0; i<rows.Count; i++)
{
da.UpdateCommand = new OleDbCommand(String.Format("UPDATE...",row[i]);
da.Update(dt);
}

inserting data into multiple tables using a web form

i would like to know what is the standard/best way of doing the following:
i have a form web app in asp.net and using C#
the user will enter data into the form and click INSERT and it will insert data into 4 different tables.
the fields are:
primarykey, animal, street, country
the form allows for multiple animals, multiple streets and multiple countries per primarykey. so when i have data like this:
[1],[rhino,cat,dog],[luigi st, paul st], [russia,israel]
i need it inserted into tables like this:
table1:
1,rhino
1,cat
1,dog
table2:
1,luigi st
1, paul st
table3:
1,russia
1,israel
questions
I'm at a total loss on how to do this. if i just had one table and one set of data per primary key i would just use the InsertQuery and do it this way, but since it is multiple tables i don't know how to do this??
what control(s) should i use in order to allow user to input multiple values? currently i am just using textboxes and thinking of separating the entries by semi colons, but that's probably not the right way.

I wanted to recommend that you take advantage of the new multirow insert statement in SQL 2008 so that you can just pass a sql statement like this:
INSERT INTO table1(id,animal_name) values (1,cat),(1,dog),(1,horse)...
To your SqlCommand but I don't know how to build a statement like that w/o risking being victim of a SQL Injection Attack.
Another alternative is to define data table types in your sql database:
And then construct a DataTable in C# that matches your datatable type definition:
DataTable t = new DataTable();
t.Columns.Add("id");
t.Columns.Add("animal_name");
foreach(var element in your animals_list)
{
DaraRow r = t.NewRow();
r.ItemArray = new object[] { element.id, element.animal_name };
t.Rows.Add(r);
}
// Assumes connection is an open SqlConnection.
using (connection)
{
// Define the INSERT-SELECT statement.
string sqlInsert = "INSERT INTO dbo.table1 (id, animal_name) SELECT nc.id, nc.animal_name FROM #animals AS nc;"
// Configure the command and parameter.
SqlCommand insertCommand = new SqlCommand(sqlInsert, connection);
SqlParameter tvpParam = insertCommand.Parameters.AddWithValue("#animals", t);
tvpParam.SqlDbType = SqlDbType.Structured;
tvpParam.TypeName = "dbo.AnimalTable";
// Execute the command.
insertCommand.ExecuteNonQuery();
}
Read more here.
Or if you are familiar with Stored Procedures, same as previous suggestion but having the stored procedure receive the DataTable t as parameter.
If none of the above work for you, create a SqlTranscation from the Connection object and iterate through each row of each data set inserting the record in the appropriate table and finally commit the transaction. Example here.

Use Checkboxes on the front end. Have a service/repository to save the user data. Something like the following:
public void UpdateUserAnimals(Guid userId, string[] animals)
{
using (SqlConnection conn = new SqlConnection("connectionstring..."))
{
using (SqlCommand cmd = new SqlCommand("Insert Into UserAnimals(UserId, Animals) values (#UserId, #Animal)"))
{
conn.Open();
cmd.Parameters.AddWithValue("#UserId", userId);
foreach(string animal in animals)
{
cmd.Parameters.AddWithValue("#Animal", animal);
cmd.ExecuteNonQuery();
}
}
}
}
There are more complex solutions, but this is a simple one.

how to update datatable in c# with code?

I want move data from database to another database.
I write 2 function. function 1 : I fill table from database1 into a datatable and named this DT
in function 2 I fill table in database2 with Dt and named its dtnull
I update dtnull in database 2
function 2:
{
SqlDataAdapter sda = new SqlDataAdapter();
sda.SelectCommand = new SqlCommand();
sda.SelectCommand.Connection = objconn;
sda.SelectCommand.CommandText = "Select * from " + TableName + "";
DataTable dtnull = new DataTable();
sda.Fill(dtnull);
SqlCommandBuilder Builder = new SqlCommandBuilder();
Builder.DataAdapter = sda;
Builder.ConflictOption = ConflictOption.OverwriteChanges;
string insertCommandSql = Builder.GetInsertCommand(true).CommandText;
foreach (DataRow Row in Dt.Rows)
{
dtnull.ImportRow(Row);
}
sda.Fill(dtnull);
sda.Update(dtnull);
}

If you need to copy SQL database then just back it up and restore. Alternatively use DTS services.

If it's just a few tables I think you can
right click on the table you want in the SQL Management studio
generate a create script to your clipboard
execute it
Go back to your original table and select all the rows
copy them
go to your new table and paste
No need to make this harder than it is.

You don't really need to use an update for this. You might try out this solution, it might be the easiest way for you do this.
http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqlbulkcopy.aspx
If you would like a LINQ solution, I could provide you with one.

There is a lot that is left unexplained. For example, do the source table and target table have the same column structure?
Can you see both database from the same SqlConnection (i.e. are they on the same machine)? If so, you can do it all in one SQL statement. Assuming you want to copy the data from table T1 in databse DB1 to table T2 in database DB2, you would write
insert DB2.dbo.T2 select * from DB1.dbo.T1
Excecute using ExecuteNonQuery.
If the databases require different SqlConnections, I would read the data from the source using a SqlDataReader and update the target row by row. I think it would be faster than using a SqlDataAdapter and DataTable since they require more structure and memory. The Update command writes the data row by row in any event.