Trait Params

Source

pub trait Params {
    // Required method
    fn bind_params(self, stmt: &mut Statement) -> Result<()>;
}

Expand description

Trait for collections of parameters to a query.

This is a private trait with no public API. There are existing implementations which should cover most use cases:

An empty tuple (()) binds no parameters to the query.
An array binds parameters that are all the same type.
The params! macro binds parameters of arbitrary types.
A closure can arbitrarily bind parameters.

Named parameters are implemented by using a tuple of ("name", value), and can be in any order. See params! for an example.

§Using a closure

If you are dynamically creating SQL queries and need to dynamically bind parameters to them, you can use a closure to accomplish this.

use sqlite3_ext::{Connection, Result, query::{ Statement, ToParam }};

fn do_thing(conn: &Connection) -> Result<i64> {
    conn.prepare("INSERT INTO tbl VALUES (?, ?)")?
        .execute(|stmt: &mut Statement| {
            "foo".bind_param(stmt, 1)?;
            "bar".bind_param(stmt, 2)?;
            Ok(())
        })
}