/****************************************************************************
** (c) Copyright IBM Corp. 2007 All rights reserved.
** 
** The following sample of source code ("Sample") is owned by International 
** Business Machines Corporation or one of its subsidiaries ("IBM") and is 
** copyrighted and licensed, not sold. You may use, copy, modify, and 
** distribute the Sample in any form without payment to IBM, for the purpose of 
** assisting you in the development of your applications.
** 
** The Sample code is provided to you on an "AS IS" basis, without warranty of 
** any kind. IBM HEREBY EXPRESSLY DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR 
** IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
** MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Some jurisdictions do 
** not allow for the exclusion or limitation of implied warranties, so the above 
** limitations or exclusions may not apply to you. IBM shall not be liable for 
** any damages you suffer as a result of using, copying, modifying or 
** distributing the Sample, even if IBM has been advised of the possibility of 
** such damages.
*****************************************************************************
**
** SOURCE FILE NAME: fnuse.sqc 
**    
** SAMPLE: How to use built-in SQL functions 
**
** SQL FUNCTION USED:
**         IDENTITY_VAL_LOCAL
**
** SQL STATEMENTS USED:
**         CREATE TABLE 
**         COMMIT
**         EXECUTE IMMEDIATE
**         VALUES
**         PREPARE
**         DECLARE CURSOR
**         OPEN
**         FETCH
**         CLOSE
**         DROP TABLE
**
**                           
*****************************************************************************
**
** For more information on the sample programs, see the README file.
**
** For information on developing embedded SQL applications see the Developing Embedded SQL Applications book.
**
** For information on using SQL statements, see the SQL Reference.
**
** For the latest information on programming, building, and running DB2 
** applications, visit the DB2 Information Center: 
**     http://publib.boulder.ibm.com/infocenter/db2luw/v9r7/index.jsp
****************************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sqlenv.h>
#include <sqlcodes.h>
#include <sqlutil.h>
#include "utilemb.h"

int ScalarFn_IDENTITY_VAL_LOCAL_Use(void);

EXEC SQL BEGIN DECLARE SECTION;
  short empno;
  char name[15];
  char strStmt[257];
  short lastIdentityValue;
  short lastIdentityValueInd;
EXEC SQL END DECLARE SECTION;

int main(int argc, char *argv[])
{
  int rc = 0;
  char dbAlias[SQL_ALIAS_SZ + 1];
  char user[USERID_SZ + 1];
  char pswd[PSWD_SZ + 1];

  /* check the command line arguments */
  rc = CmdLineArgsCheck1(argc, argv, dbAlias, user, pswd);
  if (rc != 0)
  {
    return rc;
  }

  printf("\nTHIS SAMPLE SHOWS HOW TO USE BUILT-IN SQL FUNCTIONS.\n");

  /* connect to the database */
  rc = DbConn(dbAlias, user, pswd);
  if (rc != 0)
  {
    return rc;
  }

  rc = ScalarFn_IDENTITY_VAL_LOCAL_Use();

  /* disconnect from the database */
  rc = DbDisconn(dbAlias);
  if (rc != 0)
  {
    return rc;
  }

  return 0;
} /* main */

int ScalarFn_IDENTITY_VAL_LOCAL_Use(void)
{
  int rc = 0;
  struct sqlca sqlca;

  printf("\n-----------------------------------------------------------");
  printf("\nUSE THE SQL STATEMENTS:\n");
  printf("  CREATE TABLE\n");
  printf("  COMMIT\n");
  printf("  INSERT\n");
  printf("  PREPARE\n");
  printf("  DECLARE CURSOR\n");
  printf("  OPEN\n");
  printf("  FETCH\n");
  printf("  CLOSE\n");
  printf("  VALUES\n");
  printf("  DROP TABLE\n");
  printf("TO WORK WITH THE SCALAR FUNCTION 'IDENTITY_VAL_LOCAL'.\n");

  printf("\n  CREATE TABLE empl(empno INTEGER GENERATED BY DEFAULT"
         "\n                                 AS IDENTITY(START WITH 30,"
         "\n                                             INCREMENT BY 10),"
         "\n                   name VARCHAR(10))\n");

  EXEC SQL CREATE TABLE empl(empno INTEGER GENERATED BY DEFAULT
                                          AS IDENTITY(START WITH 30,
                                                      INCREMENT BY 10),
                            name VARCHAR(10));
  EMB_SQL_CHECK("table -- create");

  printf("  COMMIT\n");

  EXEC SQL COMMIT;
  EMB_SQL_CHECK("transaction -- commit");

  printf("\n  INSERT INTO empl(name) VALUES('Sanders')\n");
  strcpy(strStmt, "INSERT INTO empl(name) VALUES('Sanders') ");

  EXEC SQL EXECUTE IMMEDIATE :strStmt;
  EMB_SQL_CHECK("table -- insert");

  printf("  VALUES IDENTITY_VAL_LOCAL() returns: ");
  EXEC SQL VALUES IDENTITY_VAL_LOCAL()
    INTO :lastIdentityValue:lastIdentityValueInd;
  EMB_SQL_CHECK("IDENTITY_VAL_LOCAL -- use");

  if (lastIdentityValueInd >= 0)
  {
    printf("%d\n", lastIdentityValue);
  }
  else
  {
    printf("NULL\n");
  }

  printf("  INSERT INTO empl(name) VALUES('Davis')\n");
  strcpy(strStmt, "INSERT INTO empl(name) VALUES('Davis') ");

  EXEC SQL EXECUTE IMMEDIATE :strStmt;
  EMB_SQL_CHECK("table -- insert");

  printf("  VALUES IDENTITY_VAL_LOCAL() returns: ");

  EXEC SQL VALUES IDENTITY_VAL_LOCAL()
    INTO :lastIdentityValue:lastIdentityValueInd;
  EMB_SQL_CHECK("IDENTITY_VAL_LOCAL -- use");

  if (lastIdentityValueInd >= 0)
  {
    printf("%d\n", lastIdentityValue);
  }
  else
  {
    printf("NULL\n");
  }

  printf("  INSERT INTO empl(name) VALUES('Yamaguchi')\n");
  strcpy(strStmt, "INSERT INTO empl(name) VALUES('Yamaguchi') ");

  EXEC SQL EXECUTE IMMEDIATE :strStmt;
  EMB_SQL_CHECK("table -- insert");

  printf("  VALUES IDENTITY_VAL_LOCAL() returns: ");

  EXEC SQL VALUES IDENTITY_VAL_LOCAL()
    INTO :lastIdentityValue:lastIdentityValueInd;
  EMB_SQL_CHECK("IDENTITY_VAL_LOCAL -- use");

  if (lastIdentityValueInd >= 0)
  {
    printf("%d\n", lastIdentityValue);
  }
  else
  {
    printf("NULL\n");
  }

  printf("  COMMIT\n");

  EXEC SQL COMMIT;
  EMB_SQL_CHECK("transaction -- commit");

  printf("\n  SELECT empno, name FROM empl\n");
  strcpy(strStmt, "SELECT empno, name FROM empl");

  EXEC SQL PREPARE stmt1 FROM :strStmt;
  EMB_SQL_CHECK("statement -- prepare");

  printf("\n    EMPNO NAME\n");
  printf("    ----- ----------\n");

  EXEC SQL DECLARE c1 CURSOR FOR stmt1;

  EXEC SQL OPEN c1;
  EMB_SQL_CHECK("cursor -- open");

  EXEC SQL FETCH c1 INTO :empno, :name;
  EMB_SQL_CHECK("cursor -- fetch");

  while (sqlca.sqlcode != 100)
  {
    printf("    %5d %-10s\n", empno, name);

    EXEC SQL FETCH c1 INTO :empno, :name;
    EMB_SQL_CHECK("cursor -- fetch");
  }

  EXEC SQL CLOSE c1;
  EMB_SQL_CHECK("cursor -- close");

  printf("\n  DROP TABLE empl\n");

  EXEC SQL DROP TABLE empl;
  EMB_SQL_CHECK("table -- drop");

  printf("  COMMIT\n");

  EXEC SQL COMMIT;
  EMB_SQL_CHECK("transaction -- commit");

  return 0;
} /* ScalarFn_IDENTITY_VAL_LOCAL_Use */