Yurttas/PL/DBL/oracle/F/03/Movie/q05.pc

 1/*  
 2REM
 3REM q05.pc
 4REM
 5REM Which stars appeared in movies produced by
 6REM 'Disney' studios in 1997 but not in 1998
 7REM 'Disney' movies.
 8REM
 9*/
10
11#include <stdio.h>
12#include <sqlca.h>
13
14#define UNAME_LEN 32
15#define PWD_LEN   16
16
17VARCHAR username[UNAME_LEN]; /* VARCHAR is an Oracle-supplied struct */
18VARCHAR password[PWD_LEN];   /* varchar can be in lower case also. */
19
20char u_name[UNAME_LEN];
21char pwd[PWD_LEN];
22
23struct {
24  char name[18];
25} starsin;
26
27void connect_to_oracle();
28void sql_error();
29
30void main(int argc, char* argv[]) {
31  connect_to_oracle();
32
33  EXEC SQL DECLARE c CURSOR FOR
34    SELECT SI.name
35    FROM Movie M, StarsIn SI
36    WHERE M.year = 1997
37      AND M.studioname = 'Disney'
38      AND M.title = SI.title
39      AND SI.name NOT IN (SELECT SI.name
40                          FROM Movie M, StarsIn SI
41                          WHERE M.year = 1998
42                            AND M.studioname = 'Disney'
43                            AND M.title = SI.title);
44
45  EXEC SQL OPEN c;
46
47  EXEC SQL WHENEVER NOT FOUND DO BREAK;
48
49  printf("\nname\n");
50  for(;;) {
51    EXEC SQL FETCH c INTO :starsin;
52    printf("%s\n", starsin.name);
53  }
54
55  EXEC SQL CLOSE c;
56
57  EXEC SQL COMMIT WORK RELEASE;
58
59  exit(0);
60}
61
62
63void sql_error(char* msg) {
64  char err_msg[128];
65  int buflen, msglen;
66
67  EXEC SQL WHENEVER SQLERROR CONTINUE;
68
69  printf("%s \n", msg);
70  buflen = sizeof(err_msg);
71  sqlglm(err_msg, &buflen, &msglen);
72  printf("%.*s \n", msglen, err_msg);
73  exit(1);
74}
75
76
77void connect_to_oracle() {
78  /* get your username/passwd from "user_pwd.txt" file */
79
80  FILE *in_file;
81  in_file = fopen("user_pwd.txt", "r");
82  fscanf(in_file, "%s", u_name);
83  fscanf(in_file, "%s", pwd);
84
85  strncpy((char *) username.arr, u_name, UNAME_LEN);
86  username.len = strlen((char *) username.arr);
87
88  strncpy((char *) password.arr, pwd, PWD_LEN);
89  password.len = strlen((char *) password.arr);
90
91  EXEC SQL WHENEVER SQLERROR DO sql_error ("ORACLE error-- ");
92  EXEC SQL CONNECT :username IDENTIFIED BY :password;
93
94  printf("connected to oracle - \n");
95}