sqlbulkcopy using sql CE
Is it possible to use SqlBulkcopy with Sq开发者_Go百科l Compact Edition e.g. (*.sdf) files?
I know it works with SQL Server 200 Up, but wanted to check CE compatibility.
If it doesnt does anyone else know the fastest way of getting a CSV type file into SQL Server CE without using DataSets (puke here)?
BULKCOPY is not supported in SQL CE. Here is the fastest way if you have a huge number of rows in your table; insert is too slow!
using (SqlCeConnection cn = new SqlCeConnection(yourConnectionString))
{
if (cn.State == ConnectionState.Closed)
cn.Open();
using (SqlCeCommand cmd = new SqlCeCommand())
{
cmd.Connection = cn;
cmd.CommandText = "YourTableName";
cmd.CommandType = CommandType.TableDirect;
using (SqlCeResultSet rs = cmd.ExecuteResultSet(ResultSetOptions.Updatable | ResultSetOptions.Scrollable))
{
SqlCeUpdatableRecord record = rs.CreateRecord();
using (var sr = new System.IO.StreamReader(yourTextFilePath))
{
string line;
while ((line = sr.ReadLine()) != null)
{
int index = 0;
string[] values = line.Split('\t');
//write these lines as many times as the number of columns in the table...
record.SetValue(index, values[index++] == "NULL" ? null : values[index - 1]);
record.SetValue(index, values[index++] == "NULL" ? null : values[index - 1]);
record.SetValue(index, values[index++] == "NULL" ? null : values[index - 1]);
rs.Insert(record);
}
}
}
}
}
Benchmark: table with 34370 rows
with inserts: 38 rows written per second
this way: 260 rows written per second
I have a SqlCeBulkCopy library here: http://sqlcebulkcopy.codeplex.com - even support IEnumerable.
Is possible to increase a lot this kind of operation. To turn this operation usefull (I mean fast and pretty safe), u can use CE DataAdapter.
By sample, no care about keys, the steps listed bellow can help u:
- Make sure that sorce and target tables have same fields structure;
- Clone a virtual datatable with a datatable from source database (your select);
- Create a CE command with the table name as commandtext (TableDirect as commandtype);
- Create a CE dataadapter from CE command;
- Create a CE commandbuilder from CE dataatapter;
- Pass the Insert command from CE commandbuilder to CE dataadapter;
Copy "n" batch rows from your source datatable to the target datatable (the clone), doing something like this:
'... previous codes For Each currentRow In sourceTable.Rows 'u can do RaiseEvent Processing(currentRow, totalRows) here with DoEvents If targetTable.Rows.Count < 100 Then targetTable.InportRow(currentRow) targetTable.Rows(targetTable.Rows.Count - 1).SetAdded Else '...Here you wll call the CE DataAdapter's Update method (da.Update(targetTable)) '...and then be sure you clone the targetTable again, erasing all previous rows. '...Do a clone again, don't do just a "clear" in the Rows collection. '...If u have an Autoincrement it will break all Foreign Keys. End If Next '... next codes
With this way u can update several rows with no much time.
I've some applications using this method and the average rate is about 1500 rows per second in a table with 5 NTEXT fields (slow) and 800000 rows.
Of course, all depends of your table's structure. IMAGE and NTEXT are both slow datatypes.
P.S.: As I said, this method don't care so much about keys, so be carefull.
No, I don't think that SqlBulkCopy
is supported (see MSDN). Perhaps throw the data in as xml and strip it apart at the server? SQL/XML is pretty good in 2005/2008.
You might also want to look at table-value-parameters, but I doubt that CE supports these.
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