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3.1 Main Program

---

The main program looks as follows:

#include <windows.h>
#include <odbcinst.h>
#include <stdio.h>
#include <stdlib.h>
#include <sqlext.h>
void main()
{
    I_SetupLicense();
    I_DefineDatabase();
    I_CreateSystemDatabanks();
    I_StartupDatabaseServer();
    I_CreateApplicationObjects();
    exit(0);
} 

3.1.1 I_SetupLicense

The first example subroutine adds a Mimer SQL license key. Note that different machines usually have different installation numbers and license keys. This routine is only needed when an application is distributed with a license key.

void I_SetupLicense()
{
    BOOL rc; 
    rc = SQLConfigDataSource(NULL, ODBC_ADD_SYS_DSN,
         "MIMER",
         "InstallationNo=12345\0"
         "LicenseKey=23CB23B7C8D33E2F206A23CDEF67\0"
         "DESCRIPTION=This is my license key\0\0");
    if (!rc) {
        I_InstError("Error adding Mimer SQL license:"); 
    }
} 

3.1.2 I_DefineDatabase

This routine defines the ODBC data source and the Mimer SQL database parameters:

void I_DefineDatabase()
{
    BOOL rc;
    rc = SQLConfigDataSource(NULL, ODBC_ADD_SYS_DSN,
         "MIMER",
         "DSN=MyODBC\0DATABASE=MyMIMER\0"
         "DIRECTORY=c:\\MyDirectory\0"
         "USERS=200\0"
         "DESCRIPTION=This is my sample database\0\0");
    if (!rc) {
        I_InstError("Error creating database definition:"); 
    }
} 

3.1.3 I_CreateSystemDatabanks

This routine starts a process that runs the Mimer SQL system databank generation program in silent mode.

void I_CreateSystemDatabanks()
{
    BOOL rc;
    rc = SQLConfigDataSource(NULL, ODBC_CONFIG_SYS_DSN,
         "MIMER",
         "DATABASE=MyMimer\0"
         "SDBGEN=-pSYSPSW MyMimer\0\0");
    if (!rc) {
        I_InstError("Error creating System Databanks:");
    }
} 

3.1.4 I_StartupDatabaseServer

The following code starts the database server:

void I_StartupDatabaseServer()
{
    BOOL rc;
    rc = SQLConfigDataSource(NULL, ODBC_CONFIG_SYS_DSN,
         "MIMER",
         "DATABASE=MyMimer\0"
         "DbServer=START\0\0");
    if (!rc) {
        I_InstError("Error starting database server:");
    }
} 

3.1.5 I_CreateApplicationObjects

This routine sets up the Mimer SQL database environment needed by the application. For clarity, error handling has been left out of this routine.

void I_CreateApplicationObjects()
{
    RETCODE rc;
    HENV hEnv;
    HDBC hCon;
    HSTMT hStmt;
    rc = SQLAllocEnv(&hEnv);
    rc = SQLAllocConnect(hEnv, &hCon);
    rc = SQLConnect(hCon,
         "MyODBC", SQL_NTS,
         "SYSADM", SQL_NTS,
         "SYSPSW", SQL_NTS);
    rc = SQLAllocStmt(hCon, &hStmt);
/*
 *  Add application specific object creation here
 */
    rc = SQLExecDirect(hStmt,
         "CREATE IDENT ...", SQL_NTS);
    .
    .
    . 
/*
 *  Done, logout from database system
 */
    rc = SQLDisconnect(hCon);
    rc = SQLFreeEnv(hEnv);
} 

To make the sample complete, you should add code for creating the Mimer SQL objects such as databanks, users, tables, and views needed to run the application.

3.1.6 I_InstError

An example of the error handling used by the other examples follows:

void I_InstError(char *pszOperation)
{
    RETCODE rc;
    WORD iError, cbErrorMsg;
    DWORD fErrorCode;
    char szErrorMsg[1000];
    printf("%s\n", pszOperation);
    for (iError = 1; iError <= 8; iError++) {
        rc = SQLInstallerError(iError,
             &fErrorCode, 
             szErrorMsg,
             sizeof(szErrorMsg),
             &cbErrorMsg);
        if (rc == SQL_NO_DATA_FOUND ||
            rc == SQL_ERROR) {
            break;
        }
        printf("%d: Error code = %d, Message = %s\n",
            iError,
            fErrorCode,
            szErrorMsg);
    }
} 

The routine SQLInstallerError is further described in SQLInstallerError and also in the Microsoft ODBC documentation.

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