From b47c185fc4b09f0ee8f8445fb1b7ea41beafa0d7 Mon Sep 17 00:00:00 2001 From: Mike Bayer Date: Sat, 18 Aug 2012 10:41:17 -0400 Subject: tighten this up --- lib/sqlalchemy/sql/expression.py | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'lib/sqlalchemy/sql/expression.py') diff --git a/lib/sqlalchemy/sql/expression.py b/lib/sqlalchemy/sql/expression.py index 969a6920b..0974b7e50 100644 --- a/lib/sqlalchemy/sql/expression.py +++ b/lib/sqlalchemy/sql/expression.py @@ -2141,21 +2141,21 @@ class _DefaultColumnComparator(operators.ColumnOperators): class ColumnElement(ClauseElement, ColumnOperators): - """Represent an element that is usable within the "column clause" portion - of a ``SELECT`` statement. + """Represent a column-oriented SQL expression suitable for usage in the + "columns" clause, WHERE clause etc. of a statement. While the most familiar kind of :class:`.ColumnElement` is the :class:`.Column` object, :class:`.ColumnElement` serves as the basis for any unit that may be present in a SQL expression, including - the columns associated with tables, aliases, and - subqueries, expressions, function calls, SQL keywords such as - ``NULL``, literals, etc. :class:`.ColumnElement` is the ultimate base - class for all such elements. + the expressions themselves, SQL functions, bound parameters, + literal expressions, keywords such as ``NULL``, etc. :class:`.ColumnElement` + is the ultimate base class for all such elements. - A :class:`.ColumnElement` provides the ability to generate new :class:`.ClauseElement` + A :class:`.ColumnElement` provides the ability to generate new + :class:`.ColumnElement` objects using Python expressions. This means that Python operators such as ``==``, ``!=`` and ``<`` are overloaded to mimic SQL operations, - and allow the construction of :class:`.ColumnElement` constructs which + and allow the instantiation of further :class:`.ColumnElement` instances which are composed from other, more fundamental :class:`.ColumnElement` objects. For example, two :class:`.ColumnClause` objects can be added together with the addition operator ``+`` to produce -- cgit v1.2.1