Constant DEFAULT 

pub const DEFAULT: ColumnMarker;

Specifies a fixed default value for new rows.

Example

#[column(DEFAULT = 0)]
count: i32,

#[column(DEFAULT = "guest")]
role: String,

For runtime-generated values (UUIDs, timestamps), use DEFAULT_FN instead.

See: https://www.postgresql.org/docs/current/ddl-default.html