SQL `is` and query params

[kamek-pf]

I'm playing with sql_query, here's the structure I'm trying to deserialize :

#[derive(Debug, QueryableByName)]
#[table_name = "some_table"]
struct User {
    id: i32,
    some_bool: bool,
}

Rust query looks like this :

let users: Vec<User> = sql_query(include_str!("test.sql"))
    .bind::<Bool, _>(true)
    .get_results(&cn)?;

SQL query looks like this :

select id, some_bool from some_table where some_bool = $1

Everything works fine with the above query, the following however, doesn't work :

select id, some_bool from some_table where some_bool is $1

I get a DatabaseError(__Unknown, "syntax error at or near \"$1\"")

Hardcoding the value works though :

select id, some_bool from some_table where some_bool is true

[weiznich]

Diesel basically passes the raw sql string without any change to the database, so this seems to be a restriction in postgresql itself or libpq. (So nothing diesel could do much about).
From looking at the postgres operator overview it seems that there are only specific arguments are supported after is (and therefore no bind).

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