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| author | Mike Bayer <mike_mp@zzzcomputing.com> | 2021-07-12 14:28:19 -0400 |
|---|---|---|
| committer | Mike Bayer <mike_mp@zzzcomputing.com> | 2021-07-12 17:10:58 -0400 |
| commit | 204ff1f60cf911b00b7494942fc58bc715dddeed (patch) | |
| tree | f26659888176bfaed484f6f462efd0414542633a /lib/sqlalchemy/sql/coercions.py | |
| parent | ca52e87268fec966f6005b1e4aa30206ae895e9e (diff) | |
| download | sqlalchemy-204ff1f60cf911b00b7494942fc58bc715dddeed.tar.gz | |
implement independent CTEs
Added new method :meth:`_sql.HasCTE.add_cte` to each of the
:func:`_sql.select`, :func:`_sql.insert`, :func:`_sql.update` and
:func:`_sql.delete` constructs. This method will add the given
:class:`_sql.CTE` as an "independent" CTE of the statement, meaning it
renders in the WITH clause above the statement unconditionally even if it
is not otherwise referenced in the primary statement. This is a popular use
case on the PostgreSQL database where a CTE is used for a DML statement
that runs against database rows independently of the primary statement.
Fixes: #6752
Change-Id: Ibf635763e40269cbd10f4c17e208850d8e8d0188
Diffstat (limited to 'lib/sqlalchemy/sql/coercions.py')
| -rw-r--r-- | lib/sqlalchemy/sql/coercions.py | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/lib/sqlalchemy/sql/coercions.py b/lib/sqlalchemy/sql/coercions.py index 1da1fee86..16a68c8ff 100644 --- a/lib/sqlalchemy/sql/coercions.py +++ b/lib/sqlalchemy/sql/coercions.py @@ -871,6 +871,10 @@ class HasCTEImpl(ReturnsRowsImpl): __slots__ = () +class IsCTEImpl(RoleImpl): + __slots__ = () + + class JoinTargetImpl(RoleImpl): __slots__ = () |