Yurttas/PL/DBL/oracle/F/03/SPJ/q09.pc

 1/*  
 2REM
 3REM q09.pc
 4REM
 5REM Double the status of all suppliers in 'Houston'.
 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 sn[4];
23  char sname[12];
24  int  status,
25  char city[16];
26} suppliers;
27
28void connect_to_oracle();
29void sql_error();
30
31void main(int argc, char* argv[]) {
32  connect_to_oracle();
33
34  EXEC SQL
35    UPDATE Suppliers
36    SET status = status*2
37    WHERE city = 'Houston';
38
39  EXEC SQL DECLARE c CURSOR FOR
40    SELECT *
41    FROM Suppliers;
42
43  EXEC SQL OPEN c;
44
45  EXEC SQL WHENEVER NOT FOUND DO BREAK;
46
47  printf("\nsn\tsname\tstatus\tcity\n");
48  for(;;) {
49    EXEC SQL FETCH c INTO :suppliers;
50    printf("%s\t%s\t%d\t%s\n", suppliers.sn,
51                               suppliers.sname,
52                               suppliers.status,
53                               suppliers.city);
54  }
55
56  EXEC SQL CLOSE c;
57
58  EXEC SQL COMMIT WORK RELEASE;
59
60  exit(0);
61}
62
63
64void sql_error(char* msg) {
65  char err_msg[128];
66  int buflen, msglen;
67
68  EXEC SQL WHENEVER SQLERROR CONTINUE;
69
70  printf("%s \n", msg);
71  buflen = sizeof(err_msg);
72  sqlglm(err_msg, &buflen, &msglen);
73  printf("%.*s \n", msglen, err_msg);
74  exit(1);
75}
76
77
78void connect_to_oracle() {
79  /* get your username/passwd from "user_pwd.txt" file */
80
81  FILE *in_file;
82  in_file = fopen("user_pwd.txt", "r");
83  fscanf(in_file, "%s", u_name);
84  fscanf(in_file, "%s", pwd);
85
86  strncpy((char *) username.arr, u_name, UNAME_LEN);
87  username.len = strlen((char *) username.arr);
88
89  strncpy((char *) password.arr, pwd, PWD_LEN);
90  password.len = strlen((char *) password.arr);
91
92  EXEC SQL WHENEVER SQLERROR DO sql_error ("ORACLE error-- ");
93  EXEC SQL CONNECT :username IDENTIFIED BY :password;
94
95  printf("connected to oracle - \n");
96}