BCP efficient batch Import

In SQL Server, many people concatenate SQL statements by repeating the Excel data read by oledb. This is not only error-prone but also inefficient. The best way is to use BCP, that is, system. data. sqlclient. sqlbulkcopy class. Not only is the speed fast, but the code is simple. The following test code imports a sheet with more than 60 thousand pieces of data, including reading (all reading is slow). It takes about 10 seconds in my development environment, the real import process takes only 4.5 seconds.

1. Using system;
2. Using system. Data;
3. Using system. Windows. forms;
4. Using system. Data. oledb;
5. Namespace windowsapplication2
6. {
7. Public partial class form1: Form
8. {
9. Public form1 ()
10. {
11. Initializecomponent ();
12. }
14. Private void button#click (Object sender, eventargs E)
15. {
16. // Test. Import Sheet 1 in Excel to sqlserver.
17. String connstring = "Server = localhost; uid = sa; Pwd = sqlgis; database = Master ";
18. System. Windows. Forms. openfiledialog FD = new openfiledialog ();
19. If (FD. showdialog () = dialogresult. OK)
20. {
21. Transferdata (FD. filename, "sheet1", connstring );
22. }
23. }
25. Public void transferdata (string excelfile, string sheetname, string connectionstring)
26. {
27. Dataset DS = new dataset ();
28. Try
29. {
30. // Obtain all data
31. String strconn = "provider = Microsoft. Jet. oledb.4.0;" + "Data Source =" + excelfile + ";" + "extended properties = Excel 8.0 ;";
32. Oledbconnection conn = new oledbconnection (strconn );
33. Conn. open ();
34. String strexcel = "";
35. Oledbdataadapter mycommand = NULL;
36. Strexcel = string. Format ("select * from [{0} $]", sheetname );
37. Mycommand = new oledbdataadapter (strexcel, strconn );
38. Mycommand. Fill (DS, sheetname );
40. // Create a table if the target table does not exist
41. String strsql = string. Format ("If object_id (& apos; {0} & apos;) is null create table {0} (", sheetname );
42. Foreach (system. Data. datacolumn C in DS. Tables [0]. columns)
43. {
44. Strsql + = string. Format ("[{0}] varchar (255),", C. columnname );
45. }
46. Strsql = strsql. Trim (& apos;, & apos;) + ")";
48. Using (system. Data. sqlclient. sqlconnection sqlconn = new system. Data. sqlclient. sqlconnection (connectionstring ))
49. {
50. Sqlconn. open ();
51. System. Data. sqlclient. sqlcommand command = sqlconn. createcommand ();
52. Command. commandtext = strsql;
53. Command. executenonquery ();
54. Sqlconn. Close ();
55. }
56. // Use bcp to import data
57. Using (system. Data. sqlclient. sqlbulkcopy BCP = new system. Data. sqlclient. sqlbulkcopy (connectionstring ))
58. {
59. BCP. sqlrowscopied + = new system. Data. sqlclient. sqlrowscopiedeventhandler (bcp_sqlrowscopied );
60. BCP. batchsize = 100; // number of rows transmitted each time
61. BCP. policyafter = 100; // number of rows prompted by the progress
62. BCP. destinationtablename = sheetname; // target table
63. BCP. writetoserver (Ds. Tables [0]);
64. }
65. }
66. Catch (exception ex)
67. {
68. System. Windows. Forms. MessageBox. Show (ex. Message );
69. }
71. }
73. // Progress display
74. Void bcp_sqlrowscopied (Object sender, system. Data. sqlclient. sqlrowscopiedeventargs E)
75. {
76. This. Text = E. rowscopied. tostring ();
77. This. Update ();
78. }
81. }
82. }

The above transferdata can be used directly. If you need to consider it carefully, you can use oledb to obtain the table structure of Excel and add columnmappings to set the control field, in this way, you can achieve the same effect as data transmission of sqlserver.

Getoledbschematable:
Using system;
Namespace consoleapplication11
...{
Class Program
...{
Public static void main ()
...{
Getexcelfileinfo (@ "C: a.xls ");
}
Private Static void getexcelfileinfo (string path)
...{
String strconn = "provider = Microsoft. Jet. oledb.4.0;" + "Data Source =" + path + ";" + "extended properties = Excel 8.0 ;";
System. Data. oledb. oledbconnection conn = new system. Data. oledb. oledbconnection (strconn );
Conn. open ();
System. Data. datatable table = conn. getoledbschematable (system. Data. oledb. oledbschemaguid. Tables, null );

Foreach (system. Data. datarow Drow in table. Rows)
...{
String tablename = Drow ["table_name"]. tostring ();
Console. writeline (tablename + ":");
System. Data. datatable tablecolumns = conn. getoledbschematable (system. Data. oledb. oledbschemaguid. columns, new object []... {null, null, tablename, null });
Foreach (system. Data. datarow drowcolumns in tablecolumns. Rows)
...{
String columnname = drowcolumns ["column_name"]. tostring ();
Console. writeline ("" + columnname );
}
}
Console. readkey (true );
}
}
}

JDBC corresponds:
Rs1_stmt.exe cutequery (SQL );
Rsmd = Rs. getmetadata ();

For (INT I = 1; I <= rsmd. getcolumncount (); I ++)
If (rsmd. getcolumntype (I) = 4) // int type
Xmlcontent + = rsmd. getcolumnname (I) + "= '" + Rs. getint (rsmd. getcolumnname (I) + "'";
Else
Xmlcontent + = rsmd. getcolumnname (I) + "= '" + Rs. getstring (rsmd. getcolumnname (I) + "'";