Re: [Sqlalchemy-tickets] [sqlalchemy] #2932: textasfrom compatibility with columns, query

[sqlalchemy <mi...@zz...>]

#2932: textasfrom compatibility with columns, query
-----------------------------------+-------------------------------
      Reporter:  zzzeek            |      Owner:  zzzeek
          Type:  defect            |     Status:  closed
      Priority:  highest           |  Milestone:  0.9.3
     Component:  sql               |   Severity:  major - 1-3 hours
    Resolution:  fixed             |   Keywords:
Progress State:  completed/closed  |
-----------------------------------+-------------------------------
Changes (by zzzeek):

 * status:  reopened => closed
 * resolution:   => fixed
 * status_field:  in progress => completed/closed


Comment:

 rbf934018a52b4fe4c43745f is as far as we can go.  I tried also doing this:

 {{{
 #!python
 --- a/lib/sqlalchemy/sql/compiler.py
 +++ b/lib/sqlalchemy/sql/compiler.py
 @@ -274,7 +274,7 @@ class _CompileLabel(visitors.Visitable):
      __slots__ = 'element', 'name'

      def __init__(self, col, name, alt_names=()):
 -        self.element = col
 +        self.element = self._element = col
          self.name = name
          self._alt_names = (col,) + alt_names

 @@ -511,7 +511,7 @@ class SQLCompiler(Compiled):
                  add_to_result_map(
                          labelname,
                          label.name,
 -                        (label, labelname, ) + label._alt_names,
 +                        (label, labelname, label._element) +
 label._alt_names,
                          label.type
                  )
 }}}

 which allows the idea of `text("select A as
 X").columns(column("A").label("X"))`, but we get into naming conflicts
 there, and test.sql.test_query's tests for label conflicts does find one.
 The issue is if there are multiple columns named "A" with different
 labels, we can't do it as above.   It's possible we could do something
 specific for `TextAsFrom`, but it would have to correct for the same
 column() present twice perhaps.  I don't think it's a need right now.

--
Ticket URL: <http://www.sqlalchemy.org/trac/ticket/2932#comment:8>
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