diff options
Diffstat (limited to 'lib/sqlalchemy/sql')
| -rw-r--r-- | lib/sqlalchemy/sql/compiler.py | 11 | ||||
| -rw-r--r-- | lib/sqlalchemy/sql/selectable.py | 3 |
2 files changed, 13 insertions, 1 deletions
diff --git a/lib/sqlalchemy/sql/compiler.py b/lib/sqlalchemy/sql/compiler.py index bc16b1429..23eff773c 100644 --- a/lib/sqlalchemy/sql/compiler.py +++ b/lib/sqlalchemy/sql/compiler.py @@ -2868,7 +2868,16 @@ class SQLCompiler(Compiled): before column list. """ - return select._distinct and "DISTINCT " or "" + if select._distinct_on: + util.warn_deprecated( + "DISTINCT ON is currently supported only by the PostgreSQL " + "dialect. Use of DISTINCT ON for other backends is currently " + "silently ignored, however this usage is deprecated, and will " + "raise CompileError in a future release for all backends " + "that do not support this syntax.", + version="1.4", + ) + return "DISTINCT " if select._distinct else "" def group_by_clause(self, select, **kw): """allow dialects to customize how GROUP BY is rendered.""" diff --git a/lib/sqlalchemy/sql/selectable.py b/lib/sqlalchemy/sql/selectable.py index 89ee7e28f..c8df637ba 100644 --- a/lib/sqlalchemy/sql/selectable.py +++ b/lib/sqlalchemy/sql/selectable.py @@ -4138,6 +4138,9 @@ class Select( the PostgreSQL dialect will render a ``DISTINCT ON (<expressions>>)`` construct. + .. deprecated:: 1.4 Using \*expr in other dialects is deprecated + and will raise :class:`_exc.CompileError` in a future version. + """ if expr: self._distinct = True |