Yurttas/PL/DBL/oracle/F/03/Company-A/q04.pc

 1/*  
 2REM
 3REM q04.pc
 4REM
 5REM For each project, list the project name and
 6REM the total hours per week (by all employees) spent
 7REM on that project.
 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 pname[16];
25  int sumhours
26} project;
27
28void connect_to_oracle();
29void sql_error();
30
31void main(int argc, char* argv[]) {
32  connect_to_oracle();
33
34  EXEC SQL DECLARE c CURSOR FOR
35    SELECT pname, SUM(hours)
36    FROM Project, WorksOn
37    WHERE pnumber = pno
38    GROUP BY pname;
39
40  EXEC SQL OPEN c;
41
42  EXEC SQL WHENEVER NOT FOUND DO BREAK;
43
44  char pname[16];
45  int sumhours
46  printf("\npname\tsumhours\n");
47  for(;;) {
48    EXEC SQL FETCH c INTO :employee;
49    printf("%s\t%d\n", project.pname,
50                       project.sumhours);
51  }
52
53  EXEC SQL CLOSE c;
54
55  EXEC SQL COMMIT WORK RELEASE;
56
57  exit(0);
58}
59
60
61void sql_error(char* msg) {
62  char err_msg[128];
63  int buflen, msglen;
64
65  EXEC SQL WHENEVER SQLERROR CONTINUE;
66
67  printf("%s \n", msg);
68  buflen = sizeof(err_msg);
69  sqlglm(err_msg, &buflen, &msglen);
70  printf("%.*s \n", msglen, err_msg);
71  exit(1);
72}
73
74
75void connect_to_oracle() {
76  /* get your username/passwd from "user_pwd.txt" file */
77
78  FILE *in_file;
79  in_file = fopen("user_pwd.txt", "r");
80  fscanf(in_file, "%s", u_name);
81  fscanf(in_file, "%s", pwd);
82
83  strncpy((char *) username.arr, u_name, UNAME_LEN);
84  username.len = strlen((char *) username.arr);
85
86  strncpy((char *) password.arr, pwd, PWD_LEN);
87  password.len = strlen((char *) password.arr);
88
89  EXEC SQL WHENEVER SQLERROR DO sql_error ("ORACLE error-- ");
90  EXEC SQL CONNECT :username IDENTIFIED BY :password;
91
92  printf("connected to oracle - \n");
93}