Module rusqlite::types [−] [src]

Traits dealing with SQLite data types.

SQLite uses a dynamic type system. Implementations of the ToSql and FromSql traits are provided for the basic types that SQLite provides methods for:

C integers and doubles (c_int and c_double)
Strings (String and &str)
Blobs (Vec<u8> and &[u8])

Additionally, because it is such a common data type, implementations are provided for time::Timespec that use a string for storage (using the same format string, "%Y-%m-%d %H:%M:%S", as SQLite's builtin datetime function. Note that this storage truncates timespecs to the nearest second. If you want different storage for timespecs, you can use a newtype. For example, to store timespecs as doubles:

ToSql and FromSql are also implemented for Option<T> where T implements ToSql or FromSql for the cases where you want to know if a value was NULL (which gets translated to None). If you get a value that was NULL in SQLite but you store it into a non-Option value in Rust, you will get a "sensible" zero value - 0 for numeric types (including timespecs), an empty string, or an empty vector of bytes.

extern crate rusqlite;
extern crate libc;

use rusqlite::types::{FromSql, ToSql, sqlite3_stmt};
use rusqlite::{Result};
use libc::c_int;
use time;

pub struct TimespecSql(pub time::Timespec);

impl FromSql for TimespecSql {
    unsafe fn column_result(stmt: *mut sqlite3_stmt, col: c_int)
            -> Result<TimespecSql> {
        let as_f64_result = FromSql::column_result(stmt, col);
        as_f64_result.map(|as_f64: f64| {
            TimespecSql(time::Timespec{ sec: as_f64.trunc() as i64,
                                        nsec: (as_f64.fract() * 1.0e9) as i32 })
        })
    }
}

impl ToSql for TimespecSql {
    unsafe fn bind_parameter(&self, stmt: *mut sqlite3_stmt, col: c_int) -> c_int {
        let TimespecSql(ts) = *self;
        let as_f64 = ts.sec as f64 + (ts.nsec as f64) / 1.0e9;
        as_f64.bind_parameter(stmt, col)
    }
}

Structs

Null	Empty struct that can be used to fill in a query parameter as `NULL`.

Constants

SQLITE_BLOB
SQLITE_FLOAT
SQLITE_INTEGER
SQLITE_NULL
SQLITE_TEXT

Traits

FromSql	A trait for types that can be created from a SQLite value.
ToSql	A trait for types that can be converted into SQLite values.

Functions

sqlite3_column_type

Type Definitions

sqlite3_stmt