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bcp_setbulkmode

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW)

bcp_setbulkmode lets you specify the column format in a bulk copy operation, setting all the column attributes in a single function call.

Syntax

  
RETCODE bcp_setbulkmode (  
   HDBC hdbc,  
   INT property,  
   void * pField,  
   INT cbField,  
   void * pRow,  
   INT cbRow  
);  

Arguments

hdbc
The bulk copy-enabled ODBC connection handle.

property
A constant of type BYTE. See the table in the Remarks section for a list of the constants.

pField
The pointer to the field terminator value.

cbField
The length (in bytes) of the field terminator value.

pRow
The pointer to the row terminator value.

cbRow
The length in bytes of the row terminator value.

Returns

SUCCEED or FAIL

Remarks

bcp_setbulkmode can be used to bulk copy out of either a query or a table. When bcp_setbulkmode is used to bulk copy out a query statement, it must be called before calling bcp_control with BCP_HINT.

bcp_setbulkmode is an alternative to using bcp_setcolfmt and bcp_columns, which only let you specify the format of one column per function call.

The following table lists the constants for the property parameter.

Property Description
BCP_OUT_CHARACTER_MODE Specifies character output mode.

Corresponds to the -c option in BCP.EXE, and to bcp_setcolfmt with BCP_FMT_TYPE property set to SQLCHARACTER.
BCP_OUT_WIDE_CHARACTER_MODE Specifies Unicode output mode.

Corresponds to the -w option in BCP.EXE and bcp_setcolfmt with BCP_FMT_TYPE property set to SQLNCHAR.
BCP_OUT_NATIVE_TEXT_MODE Specifies native types for non-character types and Unicode for character types.

Corresponds to the -N option in BCP.EXE and bcp_setcolfmt with BCP_FMT_TYPE property set to SQLNCHAR if the column type is a string (default if not a string).
BCP_OUT_NATIVE_MODE Specifies native database types.

Corresponds to the -n option in BCP.EXE and bcp_setcolfmt with BCP_FMT_TYPE property set to the default.

You should not use bcp_setbulkmode with a sequence of function calls that includes bcp_setcolfmt, bcp_control, and bcp_readfmt. For example, you should not call bcp_control(BCPTEXTFILE) and bcp_setbulkmode.

You can call bcp_control and bcp_setbulkmode for bcp_control options that do not conflict with bcp_setbulkmode. For example, you can call bcp_control(BCPFIRST) and bcp_setbulkmode.

If you attempt to call bcp_setbulkmode with a sequence of function calls that includes bcp_setcolfmt, bcp_control, and bcp_readfmt, one of the function calls will return a sequence error failure. If you choose to correct the failure, call bcp_init to reset all the settings and start over.

Below are some examples of function calls that result in a function sequence error:

bcp_init("table", DB_IN);  
bcp_setbulkmode();  
bcp_init("table", DB_OUT);  
bcp_setbulkmode();  
bcp_readfmt();  
bcp_init(NULL, DB_OUT);  
bcp_control(BCPHINTS, "select ...");  
bcp_setbulkmode();  
bcp_init("table", DB_OUT);  
bcp_setbulkmode();  
bcp_setcolfmt();  
bcp_init("table", DB_OUT);  
bcp_control(BCPDELAYREADFMT, true);  
bcp_readfmt();  
bcp_setcolfmt();  
bcp_init(NULL, DB_OUT);  
bcp_control(BCPDELAYREADFMT, true);  
bcp_setbulkmode();  
bcp_control(BCPHINTS, "select ...");  
bcp_readfmt();  
bcp_init("table", DB_OUT);  
bcp_control(BCPDELAYREADFMT, true);  
bcp_columns();  
bcp_init("table", DB_OUT);  
bcp_control(BCPDELAYREADFMT, true);  
bcp_setcolfmt();  

Example

The following sample creates four files using different settings of bcp_setbulkmode.

// compile with: sqlncli11.lib odbc32.lib  
  
#include <windows.h>  
#include <stdio.h>  
#include <tchar.h>  
#include <sqlext.h>  
#include "sqlncli.h"  
  
// Global variables  
SQLHENV g_hEnv = NULL;  
SQLHDBC g_hDbc = NULL;  
  
void ODBCCleanUp() {  
   if (g_hDbc) {  
      SQLDisconnect(g_hDbc);  
      SQLFreeHandle(SQL_HANDLE_DBC, g_hDbc);  
      g_hDbc = NULL;  
   }  
   if (g_hEnv) {  
      SQLFreeHandle(SQL_HANDLE_ENV, g_hEnv);  
      g_hEnv = NULL;  
   }  
}  
  
BOOL MakeODBCConnection(TCHAR * pszServer) {  
   TCHAR szConnectionString[500];  
   TCHAR szOutConnectionString[500];  
   SQLSMALLINT iLen;  
   SQLRETURN rc;  
  
   _sntprintf_s(szConnectionString, 500, TEXT("DRIVER={SQL Server Native Client 11.0};Server=%s;Trusted_connection=yes;"), pszServer);  
   rc = SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE,&g_hEnv);  
   if (SQL_SUCCESS != rc && SQL_SUCCESS_WITH_INFO != rc) {  
      printf("SQLAllocHandle(SQL_HANDLE_ENV...) failed\n");  
      return false;  
   }  
   rc = SQLSetEnvAttr(g_hEnv,SQL_ATTR_ODBC_VERSION, (SQLPOINTER)SQL_OV_ODBC3, SQL_IS_UINTEGER);  
   if (SQL_SUCCESS != rc && SQL_SUCCESS_WITH_INFO != rc) {  
      printf("SQLSetEnvAttr failed\n");  
      SQLFreeHandle(SQL_HANDLE_ENV, g_hEnv);  
      return false;  
   }  
   rc = SQLAllocHandle( SQL_HANDLE_DBC, g_hEnv , &g_hDbc);  
   if (SQL_SUCCESS != rc && SQL_SUCCESS_WITH_INFO != rc) {  
      printf("SQLAllocHandle(SQL_HANDLE_DBC...) failed\n");  
      SQLFreeHandle(SQL_HANDLE_ENV, g_hEnv);  
      return false;  
   }  
   // Enable BCP  
   rc = SQLSetConnectAttr(g_hDbc, SQL_COPT_SS_BCP, (SQLPOINTER)SQL_BCP_ON, SQL_IS_INTEGER);  
   if (SQL_SUCCESS != rc && SQL_SUCCESS_WITH_INFO != rc) {  
      printf("SQLSetConnectAttr(.. SQL_COPT_SS_BCP, (SQLPOINTER)SQL_BCP_ON ...) failed\n");  
      ODBCCleanUp();  
      return false;  
   }  
   // connecting ...  
   rc = SQLDriverConnect(g_hDbc,NULL, (SQLTCHAR*)szConnectionString, SQL_NTS, (SQLTCHAR*)szOutConnectionString, 500, &iLen, SQL_DRIVER_NOPROMPT);  
   if (SQL_SUCCESS != rc && SQL_SUCCESS_WITH_INFO != rc) {  
      printf("SQLDriverConnect(SQL_HANDLE_DBC...) failed\n");  
      ODBCCleanUp();  
      return false;  
   }  
   return true;  
}  
  
BOOL BCPSetBulkMode(TCHAR * pszServer, TCHAR * pszQureryOut, char BCPType, TCHAR * pszDataFile) {  
   SQLRETURN rc;  
  
   if (!MakeODBCConnection(pszServer))  
      return false;  
   rc = bcp_init(g_hDbc, NULL, pszDataFile, NULL, DB_OUT);   // bcp init for queryout  
   if (SUCCEED != rc) {  
      printf("bcp_init failed\n");  
      ODBCCleanUp();  
      return false;  
   }  
   // setbulkmode  
   char ColTerm[] = "\t";  
   char RowTerm[] = "\r\n";  
   wchar_t wColTerm[] = L"\t";  
   wchar_t wRowTerm[] = L"\r\n";  
   BYTE * pColTerm = NULL;  
   int cbColTerm = NULL;  
   BYTE * pRowTerm = 0;  
   int cbRowTerm = 0;  
   int bulkmode = -1;  
  
   if (BCPType == 'c') {   // bcp -c  
      pColTerm = (BYTE*)ColTerm;  
      pRowTerm = (BYTE*)RowTerm;  
      cbColTerm = 1;  
      cbRowTerm = 2;  
      bulkmode = BCP_OUT_CHARACTER_MODE;  
   }  
   else  
      if (BCPType == 'w') {   // bcp -w   
         pColTerm = (BYTE*)wColTerm;  
         pRowTerm = (BYTE*)wRowTerm;  
         cbColTerm = 2;  
         cbRowTerm = 4;  
         bulkmode = BCP_OUT_WIDE_CHARACTER_MODE;  
      }  
      else  
         if (BCPType == 'n')   // bcp -n  
            bulkmode = BCP_OUT_NATIVE_MODE;  
         else  
            if (BCPType == 'N')   // bcp -n  
               bulkmode = BCP_OUT_NATIVE_TEXT_MODE;  
            else {  
               printf("unknown bcp mode\n");  
               ODBCCleanUp();  
               return false;  
            }  
            rc = bcp_setbulkmode(g_hDbc, bulkmode, pColTerm, cbColTerm, pRowTerm, cbRowTerm);  
            if (SUCCEED != rc) {  
               printf("bcp_setbulkmode failed\n");  
               ODBCCleanUp();  
               return false;  
            }  
            // set queryout T-SQL statement  
            rc = bcp_control(g_hDbc, BCPHINTS , pszQureryOut);  
            if (SUCCEED != rc) {  
               printf("bcp_control(..BCP_OPTION_HINTS..) failed\n");  
               ODBCCleanUp();  
               return false;  
            }  
            // bcp copy  
            DBINT nRowsInserted = 0;  
            rc = bcp_exec(g_hDbc, &nRowsInserted);  
            if (SUCCEED != rc) {  
               printf("bcp_exec failed\n");  
               ODBCCleanUp();  
               return false;  
            }  
            printf("bcp done\n");  
            ODBCCleanUp();  
            return true;  
}  
  
int main() {  
   BCPSetBulkMode(TEXT("localhost"), TEXT("SELECT 'this is a bcp -c test', 1,2") , 'c', TEXT("bcpc.dat"));  
   BCPSetBulkMode(TEXT("localhost"), TEXT("SELECT 'this is a bcp -w test', 1,2") , 'w', TEXT("bcpw.dat"));  
   BCPSetBulkMode(TEXT("localhost"), TEXT("SELECT 'this is a bcp -c test', 1,2") , 'n', TEXT("bcpn.dat"));  
   BCPSetBulkMode(TEXT("localhost"), TEXT("SELECT 'this is a bcp -w test', 1,2") , 'N', TEXT("bcp_N.dat"));  
}  

See Also

Bulk Copy Functions