Yurttas/PL/DBL/oracle/F/03/SPJ/q13.pc

 1/*  
 2REM
 3REM q13.pc
 4REM
 5REM Delete all projects for which there are no projects.
 6REM
 7*/
 8
 9#include <stdio.h>
10#include <sqlca.h>
11
12#define UNAME_LEN 32
13#define PWD_LEN   16
14
15VARCHAR username[UNAME_LEN]; /* VARCHAR is an Oracle-supplied struct */
16VARCHAR password[PWD_LEN];   /* varchar can be in lower case also. */
17
18char u_name[UNAME_LEN];
19char pwd[PWD_LEN];
20
21struct {
22  char jn[4];
23  char jname[12];
24  char city[16];
25} projects;
26
27void connect_to_oracle();
28void sql_error();
29
30void main(int argc, char* argv[]) {
31  connect_to_oracle();
32
33  EXEC SQL
34    DELETE FROM Projects
35    WHERE JN NOT IN (SELECT JN
36                     FROM Projects);
37
38  EXEC SQL DECLARE c CURSOR FOR
39    SELECT *
40    FROM Projects;
41
42  EXEC SQL OPEN c;
43
44  EXEC SQL WHENEVER NOT FOUND DO BREAK;
45
46  printf("\njn\tjname\tcity\n");
47  for(;;) {
48    EXEC SQL FETCH c INTO :projects;
49    printf("%s\t%s\t%s\n", projects.jn,
50                           projects.jname,
51                           projects.city);
52  }
53
54  EXEC SQL CLOSE c;
55
56  EXEC SQL COMMIT WORK RELEASE;
57
58  exit(0);
59}
60
61
62void sql_error(char* msg) {
63  char err_msg[128];
64  int buflen, msglen;
65
66  EXEC SQL WHENEVER SQLERROR CONTINUE;
67
68  printf("%s \n", msg);
69  buflen = sizeof(err_msg);
70  sqlglm(err_msg, &buflen, &msglen);
71  printf("%.*s \n", msglen, err_msg);
72  exit(1);
73}
74
75
76void connect_to_oracle() {
77  /* get your username/passwd from "user_pwd.txt" file */
78
79  FILE *in_file;
80  in_file = fopen("user_pwd.txt", "r");
81  fscanf(in_file, "%s", u_name);
82  fscanf(in_file, "%s", pwd);
83
84  strncpy((char *) username.arr, u_name, UNAME_LEN);
85  username.len = strlen((char *) username.arr);
86
87  strncpy((char *) password.arr, pwd, PWD_LEN);
88  password.len = strlen((char *) password.arr);
89
90  EXEC SQL WHENEVER SQLERROR DO sql_error ("ORACLE error-- ");
91  EXEC SQL CONNECT :username IDENTIFIED BY :password;
92
93  printf("connected to oracle - \n");
94}