null_entry

/**
 * Creates an entry of the null type. Used when a column value is null and its final type is not yet known.
 * When guessing a schema from rows, a null column stays a NullDefinition until a later row reveals a real type,
 * at which point the schema merge turns it into that type made nullable.
 *
 * @return Entry<null>
 */
null_entry(string $name, ?Metadata $metadata) : Entry