analytics/informix/demo/odbcdemo/distsel.c

/***************************************************************************
*	Licensed Materials - Property of IBM and/or HCL
*
*	IBM Informix Client-SDK
*
*	Copyright IBM Corporation 1997, 2013 All rights reserved.
*	(c) Copyright HCL Technologies Ltd. 2017.  All Rights Reserved. 
*
*
*
*
*
*  Title:          distsel.c
*
*  Description:    To select data from a column that uses a DISTINCT
*                  datatype
*                  -- the column selected is 'unit_price' of the 'item'
*                     table, which is of distinct type DOLLAR based on
*                     decimal
*
*
***************************************************************************
*/


#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#ifndef NO_WIN32
#include <io.h>
#include <windows.h>
#include <conio.h>
#endif /*NO_WIN32*/

#include "infxcli.h"

#define BUFFER_LEN      25
#define ERRMSG_LEN      200

SQLCHAR   defDsn[] = "odbc_demo";


SQLINTEGER checkError (SQLRETURN       rc,
                       SQLSMALLINT     handleType,
                       SQLHANDLE       handle,
                       SQLCHAR*            errmsg)
{
    SQLRETURN       retcode = SQL_SUCCESS;

    SQLSMALLINT     errNum = 1;
    SQLCHAR		    sqlState[6];
    SQLINTEGER      nativeError;
    SQLCHAR		    errMsg[ERRMSG_LEN];
    SQLSMALLINT     textLengthPtr;


    if ((rc != SQL_SUCCESS) && (rc != SQL_SUCCESS_WITH_INFO))
    {
        while (retcode != SQL_NO_DATA)
        {
            retcode = SQLGetDiagRec (handleType, handle, errNum, sqlState, &nativeError, errMsg, ERRMSG_LEN, &textLengthPtr);

            if (retcode == SQL_INVALID_HANDLE)
            {
                fprintf (stderr, "checkError function was called with an invalid handle!!\n");
                return 1;
            }

            if ((retcode == SQL_SUCCESS) || (retcode == SQL_SUCCESS_WITH_INFO))
                fprintf (stderr, "ERROR: %d:  %s : %s \n", nativeError, sqlState, errMsg);

            errNum++;
        }

        fprintf (stderr, "%s\n", errmsg);
        return 1;   /* all errors on this handle have been reported */
    }
    else
        return 0;	/* no errors to report */
}




int main (long         argc,
          char*        argv[])
{
    /* Declare variables
    */

    /* Handles */
    SQLHDBC         hdbc;
    SQLHENV         henv;
    SQLHSTMT        hstmt;

    /* Miscellaneous variables */

    SQLCHAR         dsn[20];   /*name of the DSN used for connecting to the database*/
    SQLRETURN       rc = 0;
    SQLINTEGER      in;

    SQLCHAR         verInfoBuffer[BUFFER_LEN];
    SQLSMALLINT		verInfoLen;

    SQLCHAR*        selectStmt = (SQLCHAR *) "SELECT item_num, description, unit_price FROM item";
    SQLCHAR         description[BUFFER_LEN];
    SQLLEN          item_num, cbItemNum, cbDescription, cbUnitPrice;
    SQLREAL         unit_price;



    /*  STEP 1. Get data source name from command line (or use default)
    **          Allocate the environment handle and set ODBC version
    **          Allocate the connection handle
    **          Establish the database connection
    **          Get version information from the database server
    **          -- if version < 9.x (not UDO enabled), exit with error message
    **          Allocate the statement handle
    */

    /* If(dsn is not explicitly passed in as arg) */
    if (argc != 2)
    {
        /* Use default dsn - odbc_demo */
        fprintf (stdout, "\nUsing default DSN : %s\n", defDsn);
        strcpy ((char *)dsn, (char *)defDsn);
    }
    else
    {
        /* Use specified dsn */
        strcpy ((char *)dsn, (char *)argv[1]);
        fprintf (stdout, "\nUsing specified DSN : %s\n", dsn);
    }


    /* Allocate the Environment handle */
    rc = SQLAllocHandle (SQL_HANDLE_ENV, SQL_NULL_HANDLE, &henv);
    if (rc != SQL_SUCCESS)
    {
        fprintf (stdout, "Environment Handle Allocation failed\nExiting!!\n");
        return (1);
    }


    /* Set the ODBC version to 3.0 */
    rc = SQLSetEnvAttr (henv, SQL_ATTR_ODBC_VERSION, (SQLPOINTER) SQL_OV_ODBC3, 0);
    if (checkError (rc, SQL_HANDLE_ENV, henv, (SQLCHAR *) "Error in Step 1 -- SQLSetEnvAttr failed\nExiting!!\n"))
        return (1);


    /* Allocate the connection handle */
    rc = SQLAllocHandle (SQL_HANDLE_DBC, henv, &hdbc);
    if (checkError (rc, SQL_HANDLE_ENV, henv, (SQLCHAR *) "Error in Step 1 -- Connection Handle Allocation failed\nExiting!!\n"))
        return (1);


    /* Establish the database connection */
    rc = SQLConnect (hdbc, dsn, SQL_NTS, (SQLCHAR *) "", SQL_NTS, (SQLCHAR *) "", SQL_NTS);
    if (checkError (rc, SQL_HANDLE_DBC, hdbc, (SQLCHAR *) "Error in Step 1 -- SQLConnect failed\nExiting!!\n"))
        return (1);


    /* Get version information from the database server
       If version < 9.x (not UDO enabled), exit with error message */

    rc = SQLGetInfo (hdbc, SQL_DBMS_VER, verInfoBuffer, BUFFER_LEN, &verInfoLen);
    if (checkError (rc, SQL_HANDLE_DBC, hdbc, (SQLCHAR *) "Error in Step 1 -- SQLGetInfo failed\n"))
        return 1;

    if ((strncmp ((char *) verInfoBuffer, "09", 2)) < 0 )
    {
        fprintf (stdout, "\n** This test can only be run against UDO-enabled database server -- version 9 or higher **\n");
        return 1;
    }


    /* Allocate the statement handle */
    rc = SQLAllocHandle (SQL_HANDLE_STMT, hdbc, &hstmt );
    if (checkError (rc, SQL_HANDLE_DBC, hdbc, (SQLCHAR *) "Error in Step 1 -- Statement Handle Allocation failed\nExiting!!\n"))
        return (1);



    fprintf (stdout, "STEP 1 done...connected to database\n");




    /* STEP 2.  Retrieve data from the 'item' table and display the results
    **          Close the result set cursor
    */


    /* Retrieve data from the 'item' table */
    fprintf (stdout, "Retrieving data from 'item' table\n\n");

    rc = SQLExecDirect (hstmt, selectStmt, SQL_NTS);
    if (checkError (rc, SQL_HANDLE_STMT, hstmt, (SQLCHAR *) "Error in Step 2 -- SQLExecDirect failed\n"))
        goto Exit;

    /* Bind the result set columns */
    rc = SQLBindCol (hstmt, 1, SQL_C_LONG, &item_num, 0, &cbItemNum);
    if (checkError (rc, SQL_HANDLE_STMT, hstmt, (SQLCHAR *) "Error in Step 2 -- SQLBindCol failed (column 1)\n"))
        goto Exit;

    rc = SQLBindCol (hstmt, 2, SQL_C_CHAR, description, BUFFER_LEN, &cbDescription);
    if (checkError (rc, SQL_HANDLE_STMT, hstmt, (SQLCHAR *) "Error in Step 2 -- SQLBindCol failed (column 2)\n"))
        goto Exit;

    rc = SQLBindCol (hstmt, 3, SQL_C_FLOAT, &unit_price, 5, &cbUnitPrice);
    if (checkError (rc, SQL_HANDLE_STMT, hstmt, (SQLCHAR *) "Error in Step 2 -- SQLBindCol failed (column 3)\n"))
        goto Exit;


    while (1)
    {
        /* Fetch the data */
        rc = SQLFetch (hstmt);
        if (rc == SQL_NO_DATA_FOUND)
            break;
        else if (checkError (rc, SQL_HANDLE_STMT, hstmt, (SQLCHAR *) "Error in Step 2 -- SQLFetch failed\n"))
            goto Exit;

        /* Display the results */
        fprintf (stdout, "Item Num: %d, Unit_price (DISTINCT TYPE dollar): %5.2f, Description: %s\n", item_num, unit_price, description);

    }

    /* Close the result set cursor */
    rc = SQLCloseCursor(hstmt);
    if (checkError (rc, SQL_HANDLE_STMT, hstmt, (SQLCHAR *) "Error in Step 2 -- SQLCloseCursor failed\n"))
        goto Exit;



    fprintf (stdout, "\nSTEP 2 done...data retrieved from 'item' table\n");




Exit:

    /* CLEANUP: Close the statement handle
    **          Free the statement handle
    **          Disconnect from the datasource
    **          Free the connection and environment handles
    **          Exit
    */

    /* Close the statement handle */
    SQLFreeStmt (hstmt, SQL_CLOSE);

    /* Free the statement handle */
    SQLFreeHandle (SQL_HANDLE_STMT, hstmt);

    /* Disconnect from the data source */
    SQLDisconnect (hdbc);

    /* Free the environment handle and the database connection handle */
    SQLFreeHandle (SQL_HANDLE_DBC, hdbc);
    SQLFreeHandle (SQL_HANDLE_ENV, henv);

    fprintf (stdout,"\n\nHit <Enter> to terminate the program...\n\n");
    in = getchar ();
    return (rc);
}