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help !!!

From: "apellido jr(dot), wilfredo p(dot)" <apellido(at)mactan(dot)ph>
To: <pgsql-interfaces(at)postgresql(dot)org>
Subject: help !!!
Date: 2004-06-30 13:26:06
Message-ID: 000b01c45ea5$def68850$8616b1cb@cache (view raw or flat)
Thread:
Lists: pgsql-interfaces
Hello! im a newbie in C programing as well as Postgresql. The above example
is workin but im having difficulty regarding assigning the result of Query
Select.  here's the program

        int
        main()
        {
            char        UserName[50];                          /* holds user
state code */
            char        query_string[256];                      /* holds
constructed SQL query */
            PGconn     *conn;                                   /* holds
database connection */
            PGresult   *res;                                    /* holds
query result */

            conn = PQconnectdb("dbname=grade");                  /* connect
to the database */

            if (PQstatus(conn) == CONNECTION_BAD)               /* did the
connection fail? */
            {
                fprintf(stderr, "Connection to database failed.\n");
                fprintf(stderr, "%s", PQerrorMessage(conn));
                exit(1);
            }

            printf("Enter Username:  ");                    /* prompt user
for a state code */
            scanf("%s", UserName);

            sprintf(query_string,                               /* create an
SQL query string */
                    "SELECT username, value
                     FROM table1
                     where test = 'grade' and username = '%s'", UserName);

            res = PQexec(conn, query_string);                   /* send the
query */

            if (PQresultStatus(res) != PGRES_TUPLES_OK)         /* did the
query fail? */
            {
                fprintf(stderr, "SELECT query failed.\n");
                PQclear(res);
                PQfinish(conn);
                exit(1);
            }

            printf("\n\n\n");
            printf("Username :  %s\n\n\n", PQgetvalue(res, 0, 0));
            printf("Grade : %s  \n\n\n", PQgetvalue(res, 0, 1));

            PQclear(res);                                       /* free
result */

            PQfinish(conn);                                     /*
disconnect from the database */

            return 0;
        }

############################################################################
########


hello how can i assign to certain variable the output of PQgetvalue(res, 0,
1)? example i want to do like this ...

a = PQgetvalue(res, 0, 1)
printf("Grade : %s  \n\n\n", a );

and then after assigning the value of PQgetvalue(res, 0, 1) to a then ...

b = a \ 2;

but  it is possible to divide the output of "a" where it is a var and "b" is
integer?












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Next:From: Bruno Wolff IIIDate: 2004-06-30 13:54:50
Subject: Re: how to execute a function directly
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Subject: how to execute a function directly

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