QUERY.C
/*
PROGRAM: QURYDEMO
========
PURPOSE:
========
demonstrates a simple MDI (Multiple Document Interface)application
that allows a user to simultaneously connect to multiple
hetrogeneous databases and perform SQL queries to get results.
FUNCTIONS:
==========
InitSQLEnvironment() - Initialize ODBC library
DisplayDatabases() - Display available Data Sources
ConnectDatabase() - Connect to a specific data source
DriverConnectDatabase() - Connect through driver specific dialogs
DisplayConnections() - Display List of made connections
DisplayQueries() - Display list of Query Handles (hstmts)
NewQueryWindow() - Open a new hstmt and update displays
ChangeCurrentCursor() - Change current cursor display
ChangeCurrentQuery() - Change current query display
DisplayNewCrsrAndStmt() - update cusor & query displays
FreeConnect() - free a connection
FreeQuery() - free a query handle
CloseQueryWindow() - close a query window
ExecuteQuery() - execute a user specified query
CloseDatabases() - check if all connections are closed
FreeSQLEnvironment() - free ODBC library
DisplayError() - displays SQL Error and Warnings
COMMENTS:
=========
Created by Microsoft Corporation.
The application uses MDI Child Window Titles to store values of
connected SQLHDBCs and SQLHSTMTs. These values are also stored in the
comboboxes that are displayed on the toolbar.
*/
#include <stdio.h>
#include <string.h>
#include <windows.h>
#include "sql.h"
#include "sqlext.h"
#include "qurydemo.h"
/*
FUNCTION: InitSQLEnvironment()
COMMENTS: Allocate an environment handle for ODBC function calls.
*/
BOOL FAR PASCAL InitSQLEnvironment()
{
// reset child window count
nChildCount = 0;
// Allocate an Environment Handle
if (SQLAllocHandle(SQL_HANDLE_ENV,SQL_NULL_HANDLE,&henv) != SQL_SUCCESS)
return FALSE;
return (SQLSetEnvAttr(henv, SQL_ATTR_ODBC_VERSION,
(SQLPOINTER) SQL_OV_ODBC3, SQL_IS_INTEGER) == SQL_SUCCESS);
}
/*
FUNCTION: DisplayDatabases(HWND hWnd)
COMMENTS: Display a list of available data sources. Use
SQLDataSources function call.
*/
void FAR PASCAL DisplayDatabases(HWND hWnd)
{
SWORD nDirection; //fetch direction
SWORD nDataSourceNameLength; //DSN str length
SWORD nSourceDescriptionLength; //Driver Description str length
char szDataSourceName[MAXBUFLEN+1]; //DSN string
char szSourceDescription[MAXBUFLEN+1]; //Driver Description string
SQLRETURN nResult; //Return Code
//Call SQLDataSources, first with SQL_FETCH_FIRST and from then on
//with SQL_FETCH_NEXT until it returns SQL_NO_DATA. Add
//all returned DSNs in the provided combo box for display.
SendMessage(hWnd, CB_RESETCONTENT, 0, 0);
for (nDirection = SQL_FETCH_FIRST;
(nResult = SQLDataSources(henv, nDirection, szDataSourceName, MAXBUFLEN,
&nDataSourceNameLength, szSourceDescription, MAXBUFLEN, &nSourceDescriptionLength)) !=
SQL_NO_DATA &&
nResult != SQL_ERROR;
nDirection = SQL_FETCH_NEXT
)
SendMessage(hWnd, CB_ADDSTRING, 0, (LPARAM)(LPSTR)szDataSourceName);
SendMessage(hWnd, CB_SETCURSEL, 0, 0);
}
/*
FUNCTION: ConnectDatabase(HWND hWnd)
COMMENTS: Connect to a DSN.
*/
BOOL FAR PASCAL ConnectDatabase(HWND hWnd)
{
char szBuffer[MAXBUFLEN+1]; // buffer to display successful connection on hdbc combo-box
char szDBName[MAXBUFLEN+1]; // DSN sting
char szUserName[MAXBUFLEN+1];// User name
char szPassword[MAXBUFLEN+1];// Password
SQLHDBC hdbc; // hdbc
SQLRETURN nResult; // Result code
// check if enough windows are already open, refuse connection
if (nChildCount >= MAXCHILDWNDS) {
MessageBox(hWndFrame, MAXCHILDEXCEEDED, MAXCHLDERR, MB_OK | MB_ICONHAND);
return (FALSE);
}
// retrieve DSN, UID and PWD values from the connect dialog box
GetDlgItemText(hWnd, IDCOMBO_DATASOURCE, szDBName, MAXBUFLEN);
GetDlgItemText(hWnd, IDTEXT_USERNAME, szUserName, MAXBUFLEN);
GetDlgItemText(hWnd, IDTEXT_PASSWORD, szPassword, MAXBUFLEN);
// Allocate a new SQLHDBC. If successful then call SQLConnect using the
// allocated hdbc and supplied connection information.
if ((nResult = SQLAllocHandle(SQL_HANDLE_DBC,henv, (SQLHDBC FAR *)&hdbc)) != SQL_SUCCESS) {
DisplayError(nResult, hWnd, SQL_HANDLE_ENV, henv);
return (FALSE);
}
nResult = SQLConnect(hdbc,(LPSTR)szDBName,SQL_NTS,(LPSTR)szUserName,SQL_NTS,(LPSTR)szPassword,SQL_NTS);
// if failed to connect, free the allocated hdbc before return
if (nResult != SQL_SUCCESS && nResult != SQL_SUCCESS_WITH_INFO) {
DisplayError(nResult, hWnd, SQL_HANDLE_DBC, hdbc);
SQLFreeHandle(SQL_HANDLE_DBC,hdbc);
return (FALSE);
}
// display any connection information if driver returns SQL_SUCCESS_WITH_INFO
if (nResult == SQL_SUCCESS_WITH_INFO)
DisplayError(nResult, hWnd, SQL_HANDLE_DBC, hdbc);
// update the hdbc(s) combo-box and create a new hstmt and its
// associated window.
wsprintf(szBuffer, DSN_HDBC_FORMAT, (LPSTR)szDBName, hdbc);
nResult = (UINT)SendMessage(hWndCrsrList, CB_ADDSTRING, 0, (LPARAM)(LPSTR)szBuffer);
SendMessage(hWndCrsrList, CB_SETCURSEL, (WPARAM)nResult, 0);
SendMessage(hWndCrsrList, CB_SELECTSTRING, 0, (LPARAM)(LPSTR)szBuffer);
ChangeCurrentCursor(hWndCrsrList);
NewQueryWindow();
return (TRUE);
}
/*
FUNCTION: DriverConnectDatabase(HWND hWnd)
COMMENTS: Connect to a DSN using SQLDriverConnect function call. It
allows driver manager and drivers to interact with the user
directly to prompt for connection information.
*/
BOOL FAR PASCAL DriverConnectDatabase(HWND hWnd)
{
char szBuffer[MAXBUFLEN+1]; //display successful connection info on hdbc(s) combo-box
char szDBName[MAXBUFLEN+1]; //DSN string
SWORD swStrLen; //String length
SQLHDBC hdbc; //hdbc
SQLRETURN nResult; //result code
// Allocate a new Connection Handle.
if ((nResult = SQLAllocHandle(SQL_HANDLE_DBC,henv, (SQLHDBC FAR *)&hdbc)) != SQL_SUCCESS) {
DisplayError(nResult, hWnd, SQL_HANDLE_ENV, henv);
return (FALSE);
}
// Call SQLDriverConnect to make a connection request. Provide SQL_DRIVER_COMPLETE_REQUIRED
// flag sothat driver manager and driver can ask for connection information
// If failed to connect, free the allocated hdbc in previous step.
nResult = SQLDriverConnect(hdbc, hWnd, "", 0, szBuffer, MAXBUFLEN, &swStrLen, SQL_DRIVER_COMPLETE_REQUIRED);
if (nResult != SQL_SUCCESS && nResult != SQL_SUCCESS_WITH_INFO) {
SQLFreeHandle(SQL_HANDLE_DBC,hdbc);
return (FALSE);
}
// If driver returns additional information with SQL_SUCCESS_WITH_INFO
// flag, display the information
if (nResult == SQL_SUCCESS_WITH_INFO)
DisplayError(nResult, hWnd, SQL_HANDLE_DBC, hdbc);
// Call SQLGetInfo to find out the DSN name for the above connection.
// Note, application should not depend upon the DSN name being present
// in the returned connection string.
strcpy(szDBName, DEFDBNAME); // initialize the string value
SQLGetInfo(hdbc, SQL_DATA_SOURCE_NAME, (PTR)szDBName, MAXBUFLEN+1, &swStrLen);
if( !*szDBName)
strcpy(szDBName,"nameless");
// Display the new connection information in the hdbc(s) combo-box.
// Create a new hstmt and its associated window.
wsprintf(szBuffer, DSN_HDBC_FORMAT, (LPSTR)szDBName, hdbc);
nResult = (UINT)SendMessage(hWndCrsrList, CB_ADDSTRING, 0, (LPARAM)(LPSTR)szBuffer);
SendMessage(hWndCrsrList, CB_SETCURSEL, (WPARAM)nResult, 0);
SendMessage(hWndCrsrList, CB_SELECTSTRING, 0, (LPARAM)(LPSTR)szBuffer);
ChangeCurrentCursor(hWndCrsrList);
NewQueryWindow();
return (TRUE);
}
/*
FUNCTION: DisplayConnections(HWND hWndhdbc)
COMMENTS: Display list of available hdbc(s) in the given list box.
*/
void FAR PASCAL DisplayConnections(HWND hWndhdbc)
{
int nConnects; // # of connections
int nIndex; // counter
char szBuffer[MAXBUFLEN+1]; // string buffer
// read the information from the hdbc(s) combo-box in the tool bar
// and feed it in the given list box.
SendMessage(hWndhdbc, LB_RESETCONTENT, 0, 0);
nConnects = (int) SendMessage(hWndCrsrList, CB_GETCOUNT, 0, 0);
for (nIndex = 0; nIndex < nConnects; nIndex++) {
SendMessage(hWndCrsrList, CB_GETLBTEXT, nIndex, (LPARAM)(LPSTR)szBuffer);
SendMessage(hWndhdbc, LB_ADDSTRING, 0, (LPARAM)(LPSTR)szBuffer);
}
SendMessage(hWndhdbc, LB_SETCURSEL, 0, 0);
}
/*
FUNCTION: DisplayQueries(HWND hWndhstmt int nCrsrIndex)
COMMENTS: Display list of hstmt(s) for the currently selected hdbc
in the given listbox.
*/
void FAR PASCAL DisplayQueries(HWND hWndhstmt, HWND hWndhdbc, int nCrsrIndex)
{
char szBuffer[MAXBUFLEN+1]; // MDI child window title
HWND hWndChild; // MDI child window handle
SQLHDBC hdbc1; // hdbc in the window title
SQLHDBC hdbc2; // selected hdbc in the list box
SQLHSTMT hstmt; // hstmt in the window title
// reset the hstmt list box in the disconnect dialog box
SendMessage(hWndhstmt, LB_RESETCONTENT, 0, 0);
// go through all available MDI child windows and check if the
// hdbc in the title matches the one selected in the list box.
// if they match, use the hstmt in the window title to create
// a new entry in the hstmt(s) list box.
for (hWndChild=GetWindow(hWndMDIClient, GW_CHILD); hWndChild; hWndChild=GetWindow(hWndChild, GW_HWNDNEXT)) {
// Class name check is necessary as some of MDI child
// windows may be iconized by the user and MDIClient
// in such cases create additional windows (such as
// icon titles).
GetClassName(hWndChild, szBuffer, MAXBUFLEN);
if (strcmp(szBuffer, ODBCMDICLASS))
continue;
GetWindowText(hWndChild, szBuffer, MAXBUFLEN);
sscanf(szBuffer, SCANHDBCHSTMT_FORMAT, &hdbc1, &hstmt);
SendMessage(hWndhdbc, LB_GETTEXT, (WPARAM)nCrsrIndex, (LPARAM)(LPSTR)szBuffer);
sscanf(szBuffer, SCANHDBC_FORMAT, &hdbc2);
if (hdbc1 != hdbc2)
continue;
wsprintf(szBuffer, ((hWndChild == hWndActiveChild) ? CURQUERY_STRING: QUERY_STRING), hstmt);
SendMessage(hWndhstmt, LB_ADDSTRING, 0, (LPARAM)(LPSTR)szBuffer);
}
SendMessage(hWndhstmt, LB_SETSEL, TRUE, 0);
}
/*
FUNCTION: NewQueryWindow()
COMMENTS: Create a new hstmt on current hdbc and its associated window
*/
void FAR PASCAL NewQueryWindow()
{
int nCurrenthdbc; // current selection in the hdbc combobox
char szBuffer[MAXBUFLEN+1]; // string in the hdbc combobox on the toolbar
char szDBName[MAXBUFLEN+1]; // DSN string
SQLHDBC hdbc; // hdbc value in the combobox
SQLHSTMT hstmt; // hstmt
MDICREATESTRUCT mcs; // MDI child window create structure
SQLRETURN nResult; // Result code
szDBName[0]='\0';
szBuffer[0]= '\0';
// check if there is hdbc selected in the combobox
if ((nCurrenthdbc = (int)SendMessage(hWndCrsrList, CB_GETCURSEL, 0, 0)) == CB_ERR) {
MessageBox(hWndFrame, MAKECONNECT, NOHDBCERROR, MB_OK | MB_ICONHAND);
return;
}
// check if the number of windows exceeds MAXCHILDWNDS
if (nChildCount >= MAXCHILDWNDS) {
MessageBox(hWndFrame, MAXCHILDEXCEEDED, MAXCHLDERR, MB_OK | MB_ICONHAND);
return;
}
// Scan DSN string and hdbc value from the combo-box
SendMessage(hWndCrsrList, CB_GETLBTEXT, (WPARAM)nCurrenthdbc, (LPARAM)(LPSTR)szBuffer);
sscanf(szBuffer, SCANDSNHDBC_FORMAT, szDBName, &hdbc);
// Allocate a new Statement Handle on the scanned hdbc
if ((nResult = SQLAllocHandle(SQL_HANDLE_STMT,hdbc, &hstmt)) != SQL_SUCCESS) {
DisplayError(nResult, hWndFrame, SQL_HANDLE_DBC, hdbc);
return;
}
// create a new MDI client window. maximized, if the previous is so.
mcs.szClass = ODBCMDICLASS;
mcs.szTitle = UNTITLED;
mcs.hOwner = hAppInstance;
mcs.style = hWndActiveChild && IsZoomed(hWndActiveChild) ? WS_MAXIMIZE : 0;
mcs.x = mcs.cx = mcs.y = mcs.cy = CW_USEDEFAULT;
hWndActiveChild = (HWND)(UINT)SendMessage(hWndMDIClient, WM_MDICREATE, 0, (LPARAM)(LPMDICREATESTRUCT)&mcs);
// check if it was created, if it wasn't free up resource and flag warning
if (!hWndActiveChild) {
MessageBox(hWndFrame, CREATECHILDERR, EXECERROR, MB_OK|MB_ICONEXCLAMATION|MB_TASKMODAL);
SQLFreeHandle(SQL_HANDLE_STMT,hstmt);
return;
}
// display the DSN string, SQLHDBC and SQLHSTMT in the title of newly
// created window. Increment the child window counter
wsprintf(szBuffer, QUERY_STRING, hstmt);
SendMessage(hWndStmtList, CB_ADDSTRING, 0, (LPARAM)(LPSTR)szBuffer);
SendMessage(hWndStmtList, CB_SELECTSTRING, 0, (LPARAM)(LPSTR)szBuffer);
wsprintf(szBuffer, DSN_HDBC_HSTMT_FORMAT, (LPSTR)szDBName, hdbc, hstmt);
SetWindowText(hWndActiveChild, szBuffer);
nChildCount++;
// update the hstmt(s) combo-box in the tool bar.
ChangeCurrentQuery(hWndStmtList);
}
/*
FUNCTION: ChangeCurrentCursor(HWND hWndCrsrList)
COMMENTS: Change the displayed hdbc in the hdbc(s) combobox
Also activate the appropriate MDI child window that
has the same hdbc as the new hdbc in the combobox.
*/
void FAR PASCAL ChangeCurrentCursor(HWND hWndCrsrList)
{
int nNewhdbc; //new hdbc position
int nConnects; //# of connections
int nIndex; //counter
char szBuffer[MAXBUFLEN+1]; //string buffer
BOOL bChangedFocus; //Activate a different MDI child?
HWND hWndChild; //MDI Child window
SQLHDBC hdbc1; //hdbc in the window title
SQLHDBC hdbc2; //hdbc in the combobox
SQLHSTMT hstmt; //hstmt in the window title
// check to see if the current selection in the combo-box
// differs from the previous selection, if it is the same then
// simply return. Check is made by searching a marked string
// in the hdbc(s) combobox.
nNewhdbc = (int)SendMessage(hWndCrsrList, CB_GETCURSEL, 0, 0);
nConnects = (int)SendMessage(hWndCrsrList, CB_GETCOUNT, 0, 0);
for(nIndex = 0; nIndex < nConnects; nIndex++) {
SendMessage(hWndCrsrList, CB_GETLBTEXT, nIndex, (LPARAM)(LPSTR)szBuffer);
if (strstr(szBuffer, CUR_MARK))
break;
}
if (nIndex == nNewhdbc)
return;
// if there was a current marked hdbc in the combobox, remove the
// mark from the string and replace it in the combobox.
if (nIndex != nConnects) {
SendMessage(hWndCrsrList, CB_GETLBTEXT, nIndex, (LPARAM)(LPSTR)szBuffer);
szBuffer[strlen(szBuffer)-2] = '\0';
SendMessage(hWndCrsrList, CB_INSERTSTRING, nIndex, (LPARAM)(LPSTR)szBuffer);
SendMessage(hWndCrsrList, CB_DELETESTRING, nIndex+1, 0);
}
// Create a new marked string with currently selected hdbc string in
// the combobox and replace it with the original.
SendMessage(hWndCrsrList, CB_GETLBTEXT, nNewhdbc, (LPARAM)(LPSTR)szBuffer);
strcat(szBuffer, CUR_MARK);
SendMessage(hWndCrsrList, CB_INSERTSTRING, nNewhdbc, (LPARAM)(LPSTR)szBuffer);
SendMessage(hWndCrsrList, CB_DELETESTRING, nNewhdbc+1, 0);
SendMessage(hWndCrsrList, CB_SELECTSTRING, 0, (LPARAM)(LPSTR)szBuffer);
// reset the hstmt(s) combobox. Search through the MDI child windows
// and collect all hstmt(s) from window titles that have the same
// hdbc value as the newly selected hdbc in the hdbc(s) combo-box above.
SendMessage(hWndStmtList, CB_RESETCONTENT, 0, 0);
for (bChangedFocus=FALSE, hWndChild=GetWindow(hWndMDIClient, GW_CHILD); hWndChild; hWndChild = GetWindow(
hWndChild, GW_HWNDNEXT)) {
// check class name to skip iconized titles or other
// such non MDI Child windows
GetClassName(hWndChild, szBuffer, MAXBUFLEN);
if (strcmp(szBuffer, ODBCMDICLASS))
continue;
GetWindowText(hWndChild, szBuffer, MAXBUFLEN);
sscanf(szBuffer, SCANHDBCHSTMT_FORMAT, &hdbc1, &hstmt);
SendMessage(hWndCrsrList, CB_GETLBTEXT, (WPARAM)nNewhdbc, (LPARAM)(LPSTR)szBuffer);
sscanf(szBuffer, SCANHDBC_FORMAT, &hdbc2);
if (hdbc1 != hdbc2)
continue;
if (!bChangedFocus) {
// If the first match is found, change the active window
// and update the hstmt(s) combobox with a new entry that
// has hstmt marked with current marker.
bChangedFocus = TRUE;
hWndActiveChild = hWndChild;
SendMessage(hWndMDIClient, WM_MDIACTIVATE, (WPARAM)hWndChild, 0);
wsprintf(szBuffer, CURQUERY_STRING, hstmt);
SendMessage(hWndStmtList, CB_ADDSTRING, 0, (LPARAM)(LPSTR)szBuffer);
SendMessage(hWndStmtList, CB_SELECTSTRING, 0, (LPARAM)(LPSTR)szBuffer);
}
else {
// simply add the hstmt in the hstmt(s) combobox.
wsprintf(szBuffer, QUERY_STRING, hstmt);
SendMessage(hWndStmtList, CB_ADDSTRING, 0, (LPARAM)(LPSTR)szBuffer);
}
}
}
/*
FUNCTION: ChangeCurrentQuery(HWND hWndStmtList)
COMMENTS: Change the current selection in the hstmt(s) combobox.
Update the current marker in the combobox and activate
proper MDI Child window.
*/
void FAR PASCAL ChangeCurrentQuery(HWND hWndStmtList)
{
int nNewhstmt; //new selection in combobox
int nStmts; //# of hstmts
int nIndex; //counter
char szBuffer[MAXBUFLEN+1]; //string buffer to update displays
HWND hWndChild; //MDI child window handle
SQLHDBC hdbc1 = NULL; //hdbc in hdbc(s) combobox
SQLHDBC hdbc2 = NULL; //hdbc in child window title
SQLHSTMT hstmt1 = NULL; //newly selected hstmt
SQLHSTMT hstmt2 = NULL; //hstmt in child window title
// find the index of new selection and total number of hstmt(s)
nNewhstmt = (int)SendMessage(hWndStmtList, CB_GETCURSEL, 0, 0);
nStmts = (int)SendMessage(hWndStmtList, CB_GETCOUNT, 0, 0);
// check if the current selection is same as previous one, if
// so simply return. Check for marker to determine previous selection
for(nIndex = 0; nIndex < nStmts; nIndex++) {
SendMessage(hWndStmtList, CB_GETLBTEXT, nIndex, (LPARAM)(LPSTR)szBuffer);
if (strstr(szBuffer, CUR_MARK))
break;
}
if (nIndex == nNewhstmt)
return;
// if a previous selection was found, remove current marker
// and update it in the hstmt(s) combobox.
if (nIndex != nStmts) {
SendMessage(hWndStmtList, CB_GETLBTEXT, nIndex, (LPARAM)(LPSTR)szBuffer);
szBuffer[strlen(szBuffer)-2] = '\0';
SendMessage(hWndStmtList, CB_INSERTSTRING, nIndex, (LPARAM)(LPSTR)szBuffer);
SendMessage(hWndStmtList, CB_DELETESTRING, nIndex+1, 0);
}
// mark the current selection and update it in the hstmt(s) combobox
SendMessage(hWndStmtList, CB_GETLBTEXT, nNewhstmt, (LPARAM)(LPSTR)szBuffer);
strcat(szBuffer, CUR_MARK);
SendMessage(hWndStmtList, CB_INSERTSTRING, nNewhstmt, (LPARAM)(LPSTR)szBuffer);
SendMessage(hWndStmtList, CB_DELETESTRING, nNewhstmt+1, 0);
SendMessage(hWndStmtList, CB_SELECTSTRING, 0, (LPARAM)(LPSTR)szBuffer);
// scan hstmt value and hdbc value from current selection in
// hdbc(s) and hstmt(s) comboboxes.
sscanf(szBuffer, QUERY_STRING, &hstmt1);
SendMessage(hWndCrsrList, CB_GETLBTEXT, (UINT)SendMessage(hWndCrsrList, CB_GETCURSEL, 0, 0),
(LPARAM)(LPSTR)szBuffer);
sscanf(szBuffer, SCANHDBC_FORMAT, &hdbc1);
// go through list of MDI Child windows and match the hstmt and hdbc
// values. If a match if found (must be), activate the window
for (hWndChild=GetWindow(hWndMDIClient, GW_CHILD); hWndChild; hWndChild=GetWindow(hWndChild, GW_HWNDNEXT)) {
// ignore non MDI child windows
GetClassName(hWndChild, szBuffer, MAXBUFLEN);
if (strcmp(szBuffer, ODBCMDICLASS))
continue;
GetWindowText(hWndChild, szBuffer, MAXBUFLEN);
sscanf(szBuffer, SCANHDBCHSTMT_FORMAT, &hdbc2, &hstmt2);
if (hdbc1 == hdbc2 && hstmt1 == hstmt2) {
hWndActiveChild = hWndChild;
SendMessage(hWndMDIClient, WM_MDIACTIVATE, (WPARAM)hWndChild, 0);
break;
}
}
}
/*
FUNCTION: DisplayNewCrsrAndStmt()
COMMENTS: If user changes currently active MDI Child Window, both
hstmt(s) and hdbc(s) comboboxes need to be updated to
reflect currently selected MDI child. match the hstmt and
hdbc value in the title of MDI child to those on display
in hstmt(s) and hdbc(s) comboboxes respectively.
*/
void FAR PASCAL DisplayNewCrsrAndStmt()
{
int nConnects; // # of hdbc(s)
int nStmts; // # of hstmt(s)
int nOldhdbc; // prev selection in hdbc combobox
int nOldhstmt; // prev selection in hstmt combobox
int nIndex; // counter
char szBuffer[MAXBUFLEN+1]; // display buffer
HWND hWndChild; // MDI Child window
SQLHDBC hdbc1; // hdbc in window title
SQLHDBC hdbc2; // hdbc in hdbc(s) combobox
SQLHSTMT hstmt1; // hstmt in window title
SQLHSTMT hstmt2; // hstmt in hstmt(s) combobox
// scan hdbc and hstmt values from newly selected window
GetWindowText(hWndActiveChild, szBuffer, MAXBUFLEN);
sscanf(szBuffer, SCANHDBCHSTMT_FORMAT, &hdbc1, &hstmt1);
// search through list of hdbc(s) in hdbc combobox and find
// matching hdbc. remove marker from prev selection and add
// marker to the new selection. update combobox accordingly.
nConnects = (int)SendMessage(hWndCrsrList, CB_GETCOUNT, 0, 0);
nOldhdbc = (int)SendMessage(hWndCrsrList, CB_GETCURSEL, 0, 0);
for(hdbc2 = (SQLHDBC)(nIndex = 0); hdbc1 != hdbc2; nIndex++) {
SendMessage(hWndCrsrList, CB_GETLBTEXT, nIndex, (LPARAM)(LPSTR)szBuffer);
sscanf(szBuffer, SCANHDBC_FORMAT, &hdbc2);
}
if (--nIndex != nOldhdbc) // change in hdbc combobox required.
{
SendMessage(hWndCrsrList, CB_GETLBTEXT, nOldhdbc, (LPARAM)(LPSTR)szBuffer);
szBuffer[strlen(szBuffer)-2] = '\0';
SendMessage(hWndCrsrList, CB_INSERTSTRING, nOldhdbc, (LPARAM)(LPSTR)szBuffer);
SendMessage(hWndCrsrList, CB_DELETESTRING, nOldhdbc+1, 0);
SendMessage(hWndCrsrList, CB_GETLBTEXT, nIndex, (LPARAM)(LPSTR)szBuffer);
strcat(szBuffer, CUR_MARK);
SendMessage(hWndCrsrList, CB_INSERTSTRING, nIndex, (LPARAM)(LPSTR)szBuffer);
SendMessage(hWndCrsrList, CB_DELETESTRING, nIndex+1, 0);
SendMessage(hWndCrsrList, CB_SELECTSTRING, 0, (LPARAM)(LPSTR)szBuffer);
// reset the hstmt(s) combobox, search through the list
// of MDI child windows and find all hstmt(s) associated to
// new hdbc. Build the new list of hstmt(s) for the hstmt
// combobox. Mark the one hstmt that matches the currently
// activated MDI child window.
SendMessage(hWndStmtList, CB_RESETCONTENT, 0, 0);
for (hWndChild=GetWindow(hWndMDIClient,GW_CHILD);hWndChild;hWndChild=GetWindow(hWndChild,GW_HWNDNEXT)) {
GetClassName(hWndChild, szBuffer, MAXBUFLEN);
if (strcmp(szBuffer, ODBCMDICLASS))
continue;
GetWindowText(hWndChild, szBuffer, MAXBUFLEN);
sscanf(szBuffer, SCANHDBCHSTMT_FORMAT, &hdbc2, &hstmt2);
if (hdbc1 != hdbc2)
continue;
if (hWndActiveChild == hWndChild) {
wsprintf(szBuffer, CURQUERY_STRING, hstmt2);
SendMessage(hWndStmtList, CB_ADDSTRING, 0, (LPARAM)(LPSTR)szBuffer);
SendMessage(hWndStmtList, CB_SELECTSTRING, 0, (LPARAM)(LPSTR)szBuffer);
}
else {
wsprintf(szBuffer, QUERY_STRING, hstmt2);
SendMessage(hWndStmtList, CB_ADDSTRING, 0, (LPARAM)(LPSTR)szBuffer);
}
}
}
else // no change in hdbc combobox required
{
// go through the list of hstmt(s) in hstmt combobox.
// find the one that matches the currently activated MDI
// child window.
nOldhstmt = (int)SendMessage(hWndStmtList, CB_GETCURSEL, 0, 0);
nStmts = (int)SendMessage(hWndStmtList, CB_GETCOUNT, 0, 0);
for(hstmt2 = (SQLHDBC)(nIndex = 0); hstmt1 != hstmt2; nIndex++) {
SendMessage(hWndStmtList, CB_GETLBTEXT, nIndex, (LPARAM)(LPSTR)szBuffer);
sscanf(szBuffer, QUERY_STRING, &hstmt2);
}
if (--nIndex != nOldhstmt) // new index in hstmt differs from previous selection
{
// remove the marker from previous selection. Add
// it to the new string and update the combobox display
SendMessage(hWndStmtList, CB_GETLBTEXT, nOldhstmt, (LPARAM)(LPSTR)szBuffer);
szBuffer[strlen(szBuffer)-2] = '\0';
SendMessage(hWndStmtList, CB_INSERTSTRING, nOldhstmt, (LPARAM)(LPSTR)szBuffer);
SendMessage(hWndStmtList, CB_DELETESTRING, nOldhstmt+1, 0);
SendMessage(hWndStmtList, CB_GETLBTEXT, nIndex, (LPARAM)(LPSTR)szBuffer);
strcat(szBuffer, CUR_MARK);
SendMessage(hWndStmtList, CB_INSERTSTRING, nIndex, (LPARAM)(LPSTR)szBuffer);
SendMessage(hWndStmtList, CB_DELETESTRING, nIndex+1, 0);
SendMessage(hWndStmtList, CB_SELECTSTRING, 0, (LPARAM)(LPSTR)szBuffer);
}
}
}
/*
FUNCTION: FreeConnect(HWND hWndhdbc)
COMMENTS: Disconnect and Free the currently selected hdbc in
the hdbc listbox in disconnect dialog. Call SQLDisconnect
and SQLFreeConnect to free the hdbc. Close all MDI
child windows associated with this hdbc. That will
automatically free associated hstmt(s).
*/
void FAR PASCAL FreeConnect(HWND hWndhdbc)
{
int nIndex; // current selection in the listbox of disconnect dlg
int nCurrent; // current selection in hdbc(s) combobox
char szBuffer[MAXBUFLEN+1]; // display buffer
char szSelect[MAXBUFLEN+1]; // original selection in hdbc(s) combobox
char szDBName[MAXBUFLEN+1]; // DSN string
HWND hWndChild; // MDI Child window
SQLHDBC hdbc1 = NULL; // hdbc in the list box of disconnect dlg
SQLHDBC hdbc2 = NULL; // hdbc in the MDI child window title
szDBName[0]='\0';
// check current selection in the list box of disconnect dialog. scan
// hdbc value from the current selection.
if ((nIndex = (int)SendMessage(hWndhdbc, LB_GETCURSEL, 0, 0)) == LB_ERR)
return;
SendMessage(hWndhdbc, LB_GETTEXT, (WPARAM)nIndex, (LPARAM)(LPSTR)szBuffer);
sscanf(szBuffer, SCANDSNHDBC_FORMAT, szDBName, &hdbc1);
// go through the list of MDI child windows and find matching hdbc(s)
// close all children who have the same hdbc value. Closing them
// automatically frees associated hstmts. see CloseQueryWindow.
for(hWndChild = GetWindow(hWndMDIClient, GW_CHILD); hWndChild; ) {
// store next window handle before destroying the currentone
HWND hWndTemp = GetWindow(hWndChild, GW_HWNDNEXT);
// ignore non MDI child windows
GetClassName(hWndChild, szBuffer, MAXBUFLEN);
if (!strcmp(szBuffer, ODBCMDICLASS)) {
GetWindowText(hWndChild, szBuffer, MAXBUFLEN);
sscanf(szBuffer, SCANHDBC_TITLEFORMAT, &hdbc2);
if (hdbc1 == hdbc2) {
// destroy the window and restart search
SendMessage(hWndMDIClient, WM_MDIDESTROY, (WPARAM)hWndChild, 0);
hWndTemp = GetWindow(hWndMDIClient, GW_CHILD);
}
}
hWndChild = hWndTemp;
}
// call SQLDisconnect and SQLFreeConnect to disconnect and free hdbc
SQLDisconnect(hdbc1);
SQLFreeHandle(SQL_HANDLE_DBC,hdbc1);
// update the hdbc(s) combobox display by removing the deleted hdbc
// from the list and reselecting the previous selection
wsprintf(szBuffer, DSN_HDBC_FORMAT, (LPSTR)szDBName, hdbc1);
nCurrent = (int)SendMessage(hWndCrsrList, CB_GETCURSEL, 0, 0);
SendMessage(hWndCrsrList, CB_GETLBTEXT, nCurrent, (LPARAM)(LPSTR)szSelect);
nIndex = (int)SendMessage(hWndCrsrList, CB_FINDSTRING, 0, (LPARAM)(LPSTR)szBuffer);
SendMessage(hWndCrsrList, CB_DELETESTRING, (WPARAM)nIndex, 0);
SendMessage(hWndCrsrList, CB_SELECTSTRING, 0, (LPARAM)(LPSTR)szSelect);
// if there is no query window open and the current selected SQLHDBC
// was deleted, make sure to make the next available SQLHDBC as current
if (SendMessage(hWndCrsrList, CB_GETCOUNT, 0, 0) &&
!GetWindow(hWndMDIClient, GW_CHILD) && (nCurrent == nIndex)) {
if ((nCurrent = (int)SendMessage(hWndCrsrList, CB_GETCURSEL, 0, 0))!=CB_ERR)
return;
SendMessage(hWndCrsrList, CB_GETLBTEXT, 0, (LPARAM)(LPSTR)szSelect);
strcat(szSelect, CUR_MARK);
SendMessage(hWndCrsrList, CB_INSERTSTRING, 0, (LPARAM)(LPSTR)szSelect);
SendMessage(hWndCrsrList, CB_DELETESTRING, 1, 0);
SendMessage(hWndCrsrList, CB_SELECTSTRING, 0, (LPARAM)(LPSTR)szSelect);
}
}
/*
FUNCTION: FreeQuery(HWND hWndhstmt, HWND hWndhdbc, int nIndex)
COMMENTS: Free a query window based upon current selection in
hstmt list box in the disconnect dialog.
*/
void FAR PASCAL FreeQuery(HWND hWndhstmt, HWND hWndhdbc, int nIndex)
{
char szBuffer[MAXBUFLEN+1]; // display buffer
HWND hWndChild; // MDI child window
SQLHDBC hdbc1; // hdbc in the hdbc listbox of disconnect dlg
SQLHDBC hdbc2; // hdbc in the MDI child window title
SQLHSTMT hstmt1; // hstmt in the hstmt listbox of disconnect dlg
SQLHSTMT hstmt2; // hstmt in the MDI child window title
// scan the hstmt and hdbc values from the current selections in
// respective listboxes of disconnect dialog box.
SendMessage(hWndhstmt, LB_GETTEXT, nIndex, (LPARAM)(LPSTR)szBuffer);
sscanf(szBuffer, QUERY_STRING, &hstmt1);
SendMessage(hWndhdbc, LB_GETTEXT, (UINT)SendMessage(hWndhdbc, LB_GETCURSEL, 0, 0), (LPARAM)(LPSTR)szBuffer);
sscanf(szBuffer, SCANHDBC_FORMAT, &hdbc1);
// go through the list of MDI child windows and find matching window
// that has same values for hdbc and hstmt. Destroy the matching window.
// that will call CloseQueryWindow and thus free up associated hstmt.
for(hWndChild=GetWindow(hWndMDIClient, GW_CHILD); hWndChild; hWndChild=GetWindow(hWndChild, GW_HWNDNEXT)) {
// ignore non MDI child windows
GetClassName(hWndChild, szBuffer, MAXBUFLEN);
if (strcmp(szBuffer, ODBCMDICLASS))
continue;
GetWindowText(hWndChild, szBuffer, MAXBUFLEN);
sscanf(szBuffer, SCANHDBCHSTMT_FORMAT, &hdbc2, &hstmt2);
if (hdbc1 == hdbc2 && hstmt1 == hstmt2)
break;
}
SendMessage(hWndMDIClient, WM_MDIDESTROY, (WPARAM)hWndChild, 0);
}
/*
FUNCTION: CloseQueryWindow(HWND hWnd)
COMMENTS: Close a Query window. Call SQLFreeHandle to free
associated hstmt.
*/
void FAR PASCAL CloseQueryWindow(HWND hWnd)
{
char szBuffer[MAXBUFLEN+1]; // display buffer
char szSelect[MAXBUFLEN+1]; // current selection in hstmt(s) combobox
SQLHSTMT hstmt; // hstmt value in window title
// scan the hstmt value from the window title
GetWindowText(hWnd, szBuffer, MAXBUFLEN);
sscanf(szBuffer, SCANHSTMT_TITLEFORMAT, &hstmt);
// Drop the current Statement Handle
SQLFreeHandle(SQL_HANDLE_STMT,hstmt);
// find the matching hstmt in the hstmt(s) combobox and remove it
// from the list. Closure of a MDI child window will cause MDIClient
// to automatically activate a different child window if available.
// that will automatically refresh the hstmt and hdbc displays. See
// DisplayNewCrsrAndStmt function.
wsprintf(szBuffer, QUERY_STRING, hstmt);
SendMessage(hWndStmtList, CB_GETLBTEXT, (WPARAM)SendMessage(hWndStmtList, CB_GETCURSEL, 0, 0), (LPARAM)(LPSTR)szSelect);
SendMessage(hWndStmtList, CB_DELETESTRING, (WPARAM)SendMessage(hWndStmtList, CB_FINDSTRING, 0,
(LPARAM)(LPSTR)szBuffer), 0);
SendMessage(hWndStmtList, CB_SELECTSTRING, (WPARAM)-1, (LPARAM)(LPSTR)szSelect);
// decrement the child window counter.
nChildCount--;
}
/*
FUNCTION: ExecuteQuery()
COMMENTS: Execute the user typed SQL Statements in the currently
active MDI child window. If successful, then prepare
the list of results and display it in the child listbox.
Display errors in the ODBC function(s) failed.
*/
void FAR PASCAL ExecuteQuery()
{
char szBuffer[MAXBUFLEN+1]; // display buffer
HWND hList; // result listbox handle
SQLHDBC hdbc; // hdbc
SQLHSTMT hstmt; // hstmt
SWORD nCols = 0; // # of result columns
SWORD nCount; // index
SWORD swColType; // column data type
SWORD swColScale; // column scale
SWORD swColNull; // nullable column ?
SWORD swColLength = MAXDATALEN; // column data length
DWORD dwText; // tab stop for listbox
UDWORD udwColDef; // precision on the column
SQLRETURN nReturn; // return code
HCURSOR hOldCursor; // default cursor handle
int nRows; // # of result rows
// check if there is an active window available
if (!hWndActiveChild) {
MessageBox(hWndFrame, ((SendMessage(hWndCrsrList, CB_GETCOUNT, 0, 0) <=0) ?
MAKECONNECT : OPENWINDOW ), NOHSTMTERROR, MB_OK | MB_ICONHAND);
return;
}
// change cursor shape to hour glass
hOldCursor = SetCursor(LoadCursor((HINSTANCE)NULL, IDC_WAIT));
// initialize column data and column data length arrays
for (nCount = 0; nCount < MAX_COL; nCount++) {
dwDataLen[nCount] = 0;
rgbData[nCount][0] = '\0';
}
// scan hdbc, hstmt values
GetWindowText(hWndActiveChild, szBuffer, MAXBUFLEN);
sscanf(szBuffer, SCANHDBCHSTMT_FORMAT, &hdbc, &hstmt);
// get the user typed SQL
GetWindowText(GetDlgItem((HWND)GetWindowLong(hWndActiveChild, GWLAPP_HDLG), IDTEXT_SQL), szBuffer, MAXBUFLEN);
// execute SQL and process errors if any
// call SQLExecDirect to execute the SQL statement
nReturn = SQLExecDirect(hstmt, szBuffer, SQL_NTS);
if (nReturn != SQL_SUCCESS) {
DisplayError(nReturn, hWndActiveChild, SQL_HANDLE_STMT, hstmt);
// if the return value was just information, carry on
if (nReturn != SQL_SUCCESS_WITH_INFO) {
// Close the open result set.
SQLCloseCursor(hstmt);
SetCursor(hOldCursor);
return;
}
}
// call SQLNumResultCols to calculate the number of columns in
// the result set, if more than the MAX_COL (the array boundary)
// limit the number to MAX_COL and display truncation warning.
// if it is 0, the statement probably was a non-SELECT simply return
nReturn = SQLNumResultCols(hstmt, &nCols);
if (nCols >= MAX_COL) {
nCols = MAX_COL;
wsprintf(szDispBuffer, COLTRUNC_WARNG, MAX_COL);
MessageBox(hWndFrame, szDispBuffer, TRUNCERR, MB_OK | MB_ICONINFORMATION);
}
else if (nCols == 0) {
// Close the open result set.
SQLCloseCursor(hstmt);
SetCursor(hOldCursor);
return;
}
// call SQLBindCol to bind column data array and column data length
// array to the result set
for(nCount=0; nCount<nCols; nCount++)
SQLBindCol(hstmt, (UWORD)(nCount+1), SQL_C_CHAR, rgbData[nCount], MAXDATALEN, &dwDataLen[nCount]);
// reset the display in the list box. Set tabstops to display
// multiple columns in the list box separated by tabs.
hList = GetDlgItem((HWND)GetWindowLong(hWndActiveChild, GWLAPP_HDLG), IDLIST_RSLT);
SendMessage(hList, LB_RESETCONTENT, 0, 0);
SendMessage(hList, WM_SETREDRAW, FALSE, 0);
dwText = LISTTABSTOP;
SendMessage(hList, LB_SETTABSTOPS, (WPARAM)1, (LPARAM)(LPINT)&dwText);
// call SQLDescribeCol to get description of each column in the
// result set. Store the column name in the display buffer and
// make it the first entry in the results list box of the MDI
// child window.
for(nCount=1, szDispBuffer[0]='\0'; nCount <= nCols; nCount++) {
SQLDescribeCol(hstmt, nCount, szBuffer, MAXDATALEN, &swColLength, &swColType, &udwColDef,
&swColScale, &swColNull);
strcat(szDispBuffer, szBuffer);
dwText = strlen(szDispBuffer);
szDispBuffer[dwText++] = '\t';
szDispBuffer[dwText] = '\0';
}
if (*szDispBuffer)
szDispBuffer[strlen(szDispBuffer)-1]='\0';
SendMessage(hList, LB_ADDSTRING, 0, (LPARAM)(LPSTR)szDispBuffer);
// call SQLFetch to fetch each row of the result set. Extract data
// value and store it in the display buffer, separated by tabs.
// continue until SQLFetch fails.
for(nRows = 0; (nReturn = SQLFetch(hstmt))==SQL_SUCCESS || nReturn==SQL_SUCCESS_WITH_INFO;) {
if (nReturn != SQL_SUCCESS)
DisplayError(nReturn, hWndActiveChild, SQL_HANDLE_STMT, hstmt);
for(nCount=0, szDispBuffer[0]='\0'; nCount<nCols; nCount++) {
// check if the column is a null value?
strcat(szDispBuffer, (dwDataLen[nCount]==SQL_NULL_DATA)?NULLDATASTRING:rgbData[nCount]);
dwText = strlen(szDispBuffer);
szDispBuffer[dwText++] = '\t';
szDispBuffer[dwText] = '\0';
}
if (*szDispBuffer)
szDispBuffer[strlen(szDispBuffer)-1]='\0';
else
break;
SendMessage(hList, LB_ADDSTRING, 0, (LPARAM)(LPSTR)szDispBuffer);
if (++nRows == MAX_ROW) {
wsprintf(szDispBuffer, ROWTRUNC_WARNG, MAX_ROW);
MessageBox(hWndFrame, szDispBuffer, TRUNCERR, MB_OK | MB_ICONINFORMATION);
break;
}
}
// set the horizontal scroll extent in the list box and ask for repaint.
SendMessage(hList, LB_SETHORIZONTALEXTENT, (WPARAM)(nCols*LISTHORZSCROLL+LISTHORZEXT), 0);
SendMessage(hList, WM_SETREDRAW, TRUE, 0);
// if there was any error returned by SQLFetch, display it
if (nReturn == SQL_ERROR)
DisplayError(nReturn, hWndActiveChild, SQL_HANDLE_STMT, hstmt);
// Close the open result set.
// Unbind all bound columns.
SQLCloseCursor(hstmt);
SQLFreeStmt(hstmt, SQL_UNBIND);
// restore the cursor to default value
SetCursor(hOldCursor);
}
/*
FUNCTION: CloseDatabases()
COMMENTS: Go through all open connections (hdbcs) and hstmt(s)
and close them one by one.
*/
BOOL FAR PASCAL CloseDatabases()
{
int nIndex; // index
int nCount; // # of connected hdbc(s)
char szBuffer[MAXBUFLEN+1]; // display string buffer
HWND hWndChild; // MDI Child Window
SQLHDBC hdbc1; // hdbc value in the hdbc(s) combobox
SQLHDBC hdbc2; // hdbc value in the MDI Child window title
// get count of connected hdbc(s) from the hdbc(s) combobox on the toolbar
if (!(nCount = (int)SendMessage(hWndCrsrList, CB_GETCOUNT, 0, 0)))
return (TRUE);
// go through all available MDI child windows and for each hdbc,
// find the matching MDI child window and ask it for closure, thereby
// freeing the associated hstmt (see CloseQueryWindow). Once all
// associated hstmt(s) are freed, free the hdbc
for (nIndex = 0; nIndex < nCount; nIndex++) {
// scan current indexed hdbc from hdbc(s) combobox
SendMessage(hWndCrsrList, CB_GETLBTEXT, (WPARAM)nIndex, (LPARAM)(LPSTR)szBuffer);
sscanf(szBuffer, SCANHDBC_FORMAT, &hdbc1);
// search through the list of MDI Child Windows
for(hWndChild = GetWindow(hWndMDIClient, GW_CHILD); hWndChild; ) {
// store the next child, before destroying the current
HWND hWndTemp = GetWindow(hWndChild, GW_HWNDNEXT);
// ignore non MDI child windows
GetClassName(hWndChild, szBuffer, MAXBUFLEN);
if (!strcmp(szBuffer, ODBCMDICLASS)) {
GetWindowText(hWndChild, szBuffer, MAXBUFLEN);
sscanf(szBuffer, SCANHDBC_TITLEFORMAT, &hdbc2);
if (hdbc1 == hdbc2) {
// destroy the window and restart search
SendMessage(hWndMDIClient, WM_MDIDESTROY, (WPARAM)hWndChild, 0);
hWndTemp = GetWindow(hWndMDIClient, GW_CHILD);
}
}
hWndChild = hWndTemp;
}
// call SQLDisconnect and SQLFreeConnect to disconnect and
// free the curren hdbc resource
SQLDisconnect(hdbc1);
SQLFreeHandle(SQL_HANDLE_DBC,hdbc1);
}
// reset the hdbc(s) combobox display and display all connections
// closed message. return success to let application exit.
SendMessage(hWndCrsrList, CB_RESETCONTENT, 0, 0);
MessageBox(hWndFrame, CLOSEALLHDBC, LOGOUTINFO, MB_OK | MB_ICONINFORMATION);
return (TRUE);
}
/*
FUNCTION: FreeSQLEnvironment()
COMMENTS: Free the ODBC environment.
*/
BOOL FAR PASCAL FreeSQLEnvironment()
{
// Free up all ODBC related resources
return (SQLFreeHandle(SQL_HANDLE_ENV,henv) == SQL_SUCCESS);
}
/*
FUNCTION: DisplayError(SQLRETURN nResult, HWND hWnd, SWORD fHandleType, SQLHANDLE handle)
COMMENTS: Format and display errors or warnings.
*/
void FAR PASCAL DisplayError(SQLRETURN nResult, HWND hWnd, SWORD fHandleType, SQLHANDLE handle)
{
UCHAR szErrState[SQL_SQLSTATE_SIZE+1]; // SQL Error State string
UCHAR szErrText[SQL_MAX_MESSAGE_LENGTH+1]; // SQL Error Text string
char szBuffer[SQL_SQLSTATE_SIZE+SQL_MAX_MESSAGE_LENGTH+MAXBUFLEN+1];
// formatted Error text Buffer
SWORD wErrMsgLen; // Error message length
UDWORD dwErrCode; // Native Error code
int iSize; // Display Error Text size
SQLRETURN nErrResult; // Return Code from SQLGetDiagRec
SWORD sMsgNum = 1;
SWORD fFirstRun = TRUE;
szBuffer[0] = '\0';
do
{
// continue to bring messageboxes till all errors are displayed.
// more than one message box may be reqd. as err text has fixed
// string size.
// initialize display buffer with the string in error text buffer
strcpy(szDispBuffer, szBuffer);
// call SQLGetDiagRec function with proper ODBC handles, repeatedly until
// function returns SQL_NO_DATA. Concatenate all error strings
// in the display buffer and display all results.
while ((nErrResult = SQLGetDiagRec(fHandleType, handle, sMsgNum++,
szErrState, &dwErrCode, szErrText,
SQL_MAX_MESSAGE_LENGTH-1, &wErrMsgLen))
!= SQL_NO_DATA) {
if(nErrResult == SQL_ERROR || nErrResult == SQL_INVALID_HANDLE)
break;
wsprintf(szBuffer, SQLERR_FORMAT, (LPSTR)szErrState, dwErrCode, (LPSTR)szErrText);
iSize = strlen(szDispBuffer);
if (iSize && (iSize+strlen(szBuffer)+1) >= MAXDISPLAYSIZE)
break;
if (iSize)
strcat(szDispBuffer, "\n");
strcat(szDispBuffer, szBuffer);
}
// display proper ERROR or WARNING message with proper title
if (nResult == SQL_SUCCESS_WITH_INFO)
MessageBox(hWnd, szDispBuffer, (fFirstRun? SQLWRNMSGTITLE : SQLWRNCNTDTITLE),
MB_OK | MB_ICONINFORMATION);
else
MessageBox(hWnd, szDispBuffer, (fFirstRun? SQLERRMSGTITLE : SQLERRCNTDTITLE),
MB_OK | MB_ICONEXCLAMATION);
if (fFirstRun)
fFirstRun = FALSE;
}
while (!(nErrResult == SQL_NO_DATA || nErrResult == SQL_ERROR || nErrResult == SQL_INVALID_HANDLE));
}
/********************************************* END OF FILE **************************************************/