prepared_query/
prepared_query.rs

1//! Prepares an SQL query and executes it once for every parameter in an array
2extern crate odbc_safe;
3use odbc_safe::*;
4use std::str::from_utf8;
5
6fn main() {
7
8    let env = Environment::new().unwrap();
9    let env = env.declare_version_3().unwrap();
10    let conn = connect(&env);
11    let mut stmt = prepare_query(&conn);
12    for &year in [1968, 1993].iter() {
13        let result_set = execute_query(stmt, year);
14        stmt = print_fields(result_set);
15        println!("");
16    }
17}
18
19fn connect<V>(env: &Environment<V>) -> Connection<impl AutocommitMode>
20where
21    V: Version,
22{
23    let conn = DataSource::with_parent(env).unwrap();
24    conn.connect("TestDataSource", "", "").unwrap()
25}
26
27fn prepare_query<'a, AC: AutocommitMode>(conn: &'a Connection<AC>) -> Statement<'a, 'a, 'a, NoCursor, Prepared> {
28    let stmt = Statement::with_parent(conn).unwrap();
29    stmt.prepare("SELECT TITLE FROM MOVIES WHERE YEAR = ?")
30        .unwrap()
31}
32
33fn execute_query<'a>(
34    stmt: Statement<'a, 'a, 'a, NoCursor, Prepared>,
35    year: i32,
36) -> ResultSet<'a, 'a, 'a, Prepared> {
37    let stmt = stmt.bind_input_parameter(1, DataType::Integer, &year, None)
38        .unwrap();
39    let stmt = match stmt.execute() {
40        ReturnOption::Success(s) |
41        ReturnOption::Info(s) => s,
42        ReturnOption::NoData(_) |
43        ReturnOption::Error(_) => panic!("No Result Set"),
44    };
45    stmt.reset_parameters()
46}
47
48fn print_fields<'a>(
49    result_set: ResultSet<'a, 'a, 'a, Prepared>,
50) -> Statement<'a, 'a, 'a, NoCursor, Prepared> {
51    let mut buffer = [0u8; 512];
52    let mut cursor = match result_set.fetch() {
53        ReturnOption::Success(r) |
54        ReturnOption::Info(r) => r,
55        ReturnOption::NoData(r) |
56        ReturnOption::Error(r) => return r,
57    };
58    loop {
59        match cursor.get_data(1, &mut buffer as &mut [u8]) {
60            ReturnOption::Success(ind) |
61            ReturnOption::Info(ind) => {
62                match ind {
63                    Indicator::NoTotal => panic!("No Total"),
64                    Indicator::Null => println!("NULL"),
65                    Indicator::Length(l) => {
66                        print!("{}", from_utf8(&buffer[0..l as usize]).unwrap());
67                    }
68                }
69            }
70            ReturnOption::NoData(_) |
71            ReturnOption::Error(_) => panic!("No Field Data"),
72        }
73        cursor = match cursor.fetch() {
74            ReturnOption::Success(r) |
75            ReturnOption::Info(r) => r,
76            ReturnOption::NoData(r) |
77            ReturnOption::Error(r) => break r,
78        };
79        println!("");
80    }
81}
prepared_query/prepared_query.rs

prepared_query/
prepared_query.rs
