macro_rules! no_arg_sql_function {
($type_name:ident, $return_type:ty) => { ... };
($type_name:ident, $return_type:ty, $docs:expr) => { ... };
($type_name:ident, $return_type:ty, $docs:expr, $($constraint:ident)::+) => { ... };
}👎Deprecated since 2.0.0: Use
define_sql_function! instead. See CHANGELOG.md for migration instructionsExpand description
Declare a 0 argument SQL function for use in your code. This will generate a
unit struct, which is an expression representing calling this function. See
now for example output. now was
generated using:
no_arg_sql_function!(now, sql_types::Timestamp, "Represents the SQL NOW() function");You can optionally pass the name of a trait, as a constraint for backends which support the function.