SQLAlchemy

#1456: support for secondary/intermediary tables that are not used only for their
association
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    Reporter:  guest                     |       Owner:  zzzeek                
        Type:  defect                    |      Status:  new                   
    Priority:  medium                    |   Milestone:                        
   Component:  orm                       |    Severity:  no triage selected yet
  Resolution:                            |    Keywords:                        
Status_field:  needs questions answered  |  
-----------------------------------------+----------------------------------
Changes (by zzzeek):

  * status_field:  awaiting triage => needs questions answered

Comment:

 correct me if I'm wrong but how is this different from the association
 object pattern described in the documentation ?

-- 
Ticket URL: <http://www.sqlalchemy.org/trac/ticket/1456#comment:1>
sqlalchemy <http://www.sqlalchemy.org/>
The Database Toolkit for Python

#1456: support for secondary/intermediary tables that are not used only for their
association
-----------------------------------------+----------------------------------
    Reporter:  guest                     |       Owner:  zzzeek                
        Type:  defect                    |      Status:  new                   
    Priority:  medium                    |   Milestone:                        
   Component:  orm                       |    Severity:  no triage selected yet
  Resolution:                            |    Keywords:                        
Status_field:  needs questions answered  |  
-----------------------------------------+----------------------------------
Comment (by guest):

 just to explain, in the original post, i described what is essentially the
 association object pattern as a way of distinguishing / comparing with the
 problem. the association object pattern allows you to differentiate
 between two scenarios that are blurred together when using a single
 relation with a secondary table. i would like to see a way to tell these
 scenarios apart when *not* using the association object pattern!

-- 
Ticket URL: <http://www.sqlalchemy.org/trac/ticket/1456#comment:3>
sqlalchemy <http://www.sqlalchemy.org/>
The Database Toolkit for Python

#1456: support for secondary/intermediary tables that are not used only for their
association
-----------------------------------------+----------------------------------
    Reporter:  guest                     |       Owner:  zzzeek                
        Type:  defect                    |      Status:  new                   
    Priority:  medium                    |   Milestone:                        
   Component:  orm                       |    Severity:  no triage selected yet
  Resolution:                            |    Keywords:                        
Status_field:  needs questions answered  |  
-----------------------------------------+----------------------------------
Comment (by guest):

 trying to create a relation to map from table1 to table3 over a hidden
 intermediary table2, so table3 can be addressed as table1.table3.
 association object pattern creates two relations, so table3 would be
 addressed table1.table2.table3, which as i said originally, you can test
 whether or not the association exists yet by checking if table1.table2 is
 None. but with the direct relation (that hides the intermediary), you
 cannot test if the association exists yet as table1.table3 == None in two
 scenarions: if the association has not been made, or if the association
 has only been made half way.

-- 
Ticket URL: <http://www.sqlalchemy.org/trac/ticket/1456#comment:2>
sqlalchemy <http://www.sqlalchemy.org/>
The Database Toolkit for Python

#1456: support for secondary/intermediary tables that are not used only for their
association
-----------------------------------------+----------------------------------
    Reporter:  guest                     |       Owner:  zzzeek                
        Type:  defect                    |      Status:  new                   
    Priority:  medium                    |   Milestone:                        
   Component:  orm                       |    Severity:  no triage selected yet
  Resolution:                            |    Keywords:                        
Status_field:  needs questions answered  |  
-----------------------------------------+----------------------------------
Comment (by zzzeek):

 if your association table stores more columns than just the association,
 you should be using the association object pattern.   the feature you
 describe is not clear to me (a code example would be best).

-- 
Ticket URL: <http://www.sqlalchemy.org/trac/ticket/1456#comment:4>
sqlalchemy <http://www.sqlalchemy.org/>
The Database Toolkit for Python

#1456: support for secondary/intermediary tables that are not used only for their
association
-----------------------------------------+----------------------------------
    Reporter:  guest                     |       Owner:  zzzeek                
        Type:  defect                    |      Status:  new                   
    Priority:  medium                    |   Milestone:                        
   Component:  orm                       |    Severity:  no triage selected yet
  Resolution:                            |    Keywords:                        
Status_field:  needs questions answered  |  
-----------------------------------------+----------------------------------
Comment (by guest):

 while using the association object pattern will suffice, it would be nice
 to be able to use a table as a secondary association table while at the
 same time using it in a normal 1:1 relation.

 will attach some code with a bit more of an explanation.

-- 
Ticket URL: <http://www.sqlalchemy.org/trac/ticket/1456#comment:5>
sqlalchemy <http://www.sqlalchemy.org/>
The Database Toolkit for Python

#1456: support for secondary/intermediary tables that are not used only for their
association
-----------------------------------------+----------------------------------
    Reporter:  guest                     |       Owner:  zzzeek                
        Type:  defect                    |      Status:  closed                
    Priority:  medium                    |   Milestone:                        
   Component:  orm                       |    Severity:  no triage selected yet
  Resolution:  worksforme                |    Keywords:                        
Status_field:  needs questions answered  |  
-----------------------------------------+----------------------------------
Changes (by zzzeek):

  * status:  new => closed
  * resolution:  => worksforme

Comment:

 please see the associationproxy documentation.  it provides exactly this
 syntax.

-- 
Ticket URL: <http://www.sqlalchemy.org/trac/ticket/1456#comment:6>
sqlalchemy <http://www.sqlalchemy.org/>
The Database Toolkit for Python