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; }
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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?
