ColumnTag

class lsst.daf.relation.ColumnTag(*args, **kwargs)

Bases: collections.abc.Hashable, typing.Protocol

An interface for objects that represent columns in a relation.

See Column Tags for details.

Attributes Summary

is_key Whether this column can be used for deduplication and join equality-constraints (bool).
qualified_name A string that is just as unique as this ColumnTag is, for use in engines that require a string for column names (str).

Attributes Documentation

is_key

Whether this column can be used for deduplication and join equality-constraints (bool).

Columns that are not keys are assumed to always be accompanied in relations by related key columns that should be used instead.

qualified_name

A string that is just as unique as this ColumnTag is, for use in engines that require a string for column names (str).

This does not need to be limited to avoid special characters; we assume it can and will be appropriately quoted when necessary.