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closedxml to datatable without looping

at work I've used closedXML in the past to go from a datatable or dataset to excel extremely quickly without looping. Now I need to go the other way but the only documentation I can find on closed XMl or anything else to go from excel to datatable is to loop. I can't imagine with the current demand for speed, the large amounts of data that can go into excel and the widespread use of Office that nobody has figured out a faster way than looping.
Is there a way in closed XML or another reasonably sized, safe library that quickly moves excel to datables or other system.data objects such as datasets without looping?

You can use a plain OleDb connection to read data from a worksheet into a DataTable:
string strExcelConn = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=c:\filename.xlsx;Extended Properties='Excel 12.0 Xml;HDR=YES;'";
using (OleDbConnection connExcel = new OleDbConnection(strExcelConn))
{
string selectString = "SELECT * FROM [CA$A1:D500]";
using (OleDbCommand cmdExcel = new OleDbCommand(selectString,connExcel))
{
cmdExcel.Connection = connExcel;
connExcel.Open();
DataTable dt=new DataTable();
OleDbDataAdapter adp = new OleDbDataAdapter();
adp.SelectCommand = cmdExcel;
adp.FillSchema(dt, SchemaType.Source);
adp.Fill(dt);
int range=dt.Columns.Count;
int row = dt.Rows.Count;
}
}

Importing Excel files with a large number of columns header into mysql with c#

i just was just wondering, how do i import large excel files into mysql with c#? My coding experience isn't great and i was hoping if there's anyone out there who could give me some rough idea to start on it. So far, i was able to load excel files into datagridview with the following codes:
string PathConn = " Provider=Microsoft.JET.OLEDB.4.0;Data Source=" + pathTextBox.Text + ";Extended Properties =\"Excel 8.0;HDR=Yes;\";";
OleDbConnection conn = new OleDbConnection(PathConn);
conn.Open();
OleDbDataAdapter myDataAdapter = new OleDbDataAdapter("Select * from [" + loadTextBox.Text + "$]", conn);
table = new DataTable();
myDataAdapter.Fill(table);
but after that, i don't know how i could extract the information and save it into mysql database. Assuming i have a empty scheme created before, how do i work on uploading excel files into mysql? thanks.

I think you would then need to loop over the items in the datatable and do something with them (maybe an insert statement to your DB)
like so
foreach(DataRow dr in table.Rows)
{
string s = dr[0].ToString() // this will be the first column in the datatabl as they are zero indexed
}

this is what i do in data migration scenarios from one SQL Server to another or DataFiles to SQL:
Create the new Table on the destination SQL Server (Column names, Primary Key etc.)
Load existing Data into a DataTable (Thats what you did already)
Now Query the new Table with the DataAdapter into another DataTable (Same as you did with the excel file except you now query the SQL Table.)
Load OldData from 'table' into 'newTable' using DataTable Method "Load()"
string PathConn = (MYSQL Connection String goes here)
OleDbConnection conn = new OleDbConnection(PathConn);
conn.Open();
OleDbDataAdapter myDataAdapter = new OleDbDataAdapter("Select * from [" + loadTextBox.Text + "$]", conn);
newTable = new DataTable();
myDataAdapter.Fill(newTable);
Now use the Load() Method on the new table:
newTable.Load(table.CreateDataReader(), <Specify LoadOption here>)
Matching columns will be imported into the new DataTable. (You can ensure the mapping through using Aliases in the select statements)
After Loading the existing Data into the new Table you will be able to use an DataAdapter to write the changes back to database.
Example for writing data back: ConnString - connection String for DB,
SelectStmt (can use the same as you did on the empty Table before) and provide the newTable as dtToWrite
public static void writeDataTableToServer(string ConnString, string selectStmt, DataTable dtToWrite)
{
using (OdbcConnection odbcConn = new OdbcConnection(ConnString))
{
odbcConn.Open();
using (OdbcTransaction trans = odbcConn.BeginTransaction())
{
using (OdbcDataAdapter daTmp = new OdbcDataAdapter(selectStmt, ConnString))
{
using (OdbcCommandBuilder cb = new OdbcCommandBuilder(daTmp))
{
try
{
cb.ConflictOption = ConflictOption.OverwriteChanges;
daTmp.UpdateBatchSize = 5000;
daTmp.SelectCommand.Transaction = trans;
daTmp.SelectCommand.CommandTimeout = 120;
daTmp.InsertCommand = cb.GetInsertCommand();
daTmp.InsertCommand.Transaction = trans;
daTmp.InsertCommand.CommandTimeout = 120;
daTmp.UpdateCommand = cb.GetUpdateCommand();
daTmp.UpdateCommand.Transaction = trans;
daTmp.UpdateCommand.CommandTimeout = 120;
daTmp.DeleteCommand = cb.GetDeleteCommand();
daTmp.DeleteCommand.Transaction = trans;
daTmp.DeleteCommand.CommandTimeout = 120;
daTmp.Update(dtToWrite);
trans.Commit();
}
catch (OdbcException ex)
{
trans.Rollback();
throw ex;
}
}
}
}
odbcConn.Close();
}
}
Hope this helps.
Primary Key on the newTable is necessary, otherwise you might get a CommandBuilder exception.
BR
Therak

Your halfway there, You have obtained the information from the Excel spreadsheet and have it stored in a DataTable.
The first thing you need to do before you look to import a significant amount of data into SQL is validate what you have read in from the spreadsheets.
You have a few options, one of which is do something very similar to how you read in your data and that is use a SQLAdapter to perform am INSERT into the SQL Database. All your really needing to do in this case is create a new connection and write the INSERT command.
There are many example of doing this on here.
Another option which i would use, is LINQ to CSV (http://linqtocsv.codeplex.com/).
With this you can load all of your data into class objects which makes it easier to validate each object before you perform your INSERT into SQL.
If you have limited experience then use the SQLAdapter to connect to you DB.
Good Luck

excel data to datagridview through dataset using OLE skips the initial blank rows and blank columns

I am using OLE related API's for reading data to DataSet and later to view in DataGridView. The source is an excel file. If the first row or column is empty than that row or column is getting skipped. I wish to read the data irrespective of empty/has data. Other rows/columns even if its empty its working fine, but only starting is missing.
I read about ColumnHeader and tried changing connectionString (HDR=NO) and others but nothing worked out.
Any additional things need to be specified while calling the API? One to one mapping with the excel column and the DataGridView column is missing because of skipping this initial blank rows/columns.
Anything needs to be added/modified to this OleDbDataAdapter parameter, which actually reads the data and fills to dataset:
OleDbDataAdapter cmd = new System.Data.OleDb.OleDbDataAdapter(
"select * from [" + worksheetName + "$]", con);
Yes, I am setting some required information and calling a method to read data from each sheet. I am not doing any action on the rows/columns except reading them.
OleDbConnection con = new System.Data.OleDb.OleDbConnection(connectionString);
System.Data.DataTable getWorksheetData(OleDbConnection con, OleDbDataAdapter cmd)
{
con.Open();
System.Data.DataSet excelDataSet = new DataSet();
cmd.Fill(excelDataSet);
con.Close();
return excelDataSet.Tables[0];
}
My connection string is:
string connectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" +
fileName + "; Extended Properties=\"Excel 12.0 Xml;HDR=NO;Mode=Read;ReadOnly=True;\"";

Reading Data From MS Excel in .net

I have written a piece of code that reads excel data in data table through ado.net. Now i have seen a strange behavior, That the column data type in ms excel is specified as general, but if the 1st row of the excel of that particular column contains some text, ado.net is unable to read numbers in that particular column and if 1st row contains some numeric information ado.net is unable to read textual data of that particular column. here is the code i am using to read data from excel.
string excelConString = #"Provider=Microsoft.Jet.OLEDB.4.0;
Data Source=D:\A.xls;
Extended Properties=""Excel 8.0;HDR=YES;""";
var oleDbConnection = new OleDbConnection(excelConString);
var cmd = oleDbConnection.CreateCommand();
cmd.CommandText = "select * from [WorkSheet$] where ID>=1500";
OleDbDataAdapter da = new OleDbDataAdapter(cmd);
DataTable dt = new DataTable();
da.Fill(dt);
Any help would be appreciated.
Regards
Ahsan Iqbal

change your connectionstring to
string excelConString = #"Provider=Microsoft.Jet.OLEDB.4.0;
Data Source=D:\A.xls;
Extended Properties=""Excel 8.0;HDR=YES;IMEX=1;TypeGuessRows=0;ImportMixedTypes=Text"""

Excel through OleDb shows numbers differently...depending on whether spreadsheet is open?

I'm opening an Excel worksheet into a DataTable using OleDb like this:
string select = string.Format("SELECT * FROM [{0}$]", worksheetName);
using (var con = new OleDbConnection(connectionString))
using (var adapter = new OleDbDataAdapter(select, con))
{
con.Open();
var dt = new DataTable();
adapter.Fill(dt);
con.Close();
return dt;
}
Then I loop through the rows of the DataTable reading various bits of data like this:
decimal charge;
bool isChargeReadable =
decimal.TryParse(row["Charge"].ToString(), out charge);
I discovered just now that my code was choking on cells with dollar amounts such as "$1100.00", which it can't parse to decimal. Not so surprising...except that this is code that was working perfectly before just now.
Further investigation revealed that if I run this code while the workbook is open, it sees one of those cells as "1100". If I run it while the workbook is closed, it sees "$1100.00".
Why is this happening? Obviously I'll have to rework my code to function while the workbook is closed, but why would it make a difference? I would've thought it would just be reading the saved workbook.
The connection string I'm using is this...
"Provider=Microsoft.Jet.OLEDB.4.0;
Data Source={0};
Extended Properties=""Excel 8.0;HDR=NO;IMEX=1"";"
...where {0} is replaced by the Excel file name, of course.

I've found that my oledb operations work better in excel withOUT an IMEX=number set. Perhaps your problem is there?