Hello!
It looks that SQLAlchemy doesn't properly handle union with limits in
the following scenario:
res1 = Session.query( Messages ).order_by( Messages.ts ).limit(100)
res2 = Session.query( Messages1 ).order_by( Messages1.ts ).limit(100)
res3 = res1.union_all( res2 )
SQLAlchemy creates the following final query:
SELECT <fields> FROM Messages order by ts limit 100
UNION ALL SELECT <fields> FROM Messages1 order by ts limit 100
Which fails with:
ProgrammingError: (psycopg2.ProgrammingError) syntax error at or near
"UNION"
To fix this, both queries should be enclosed in parenthesis:
(SELECT <fields> FROM Messages order by ts limit 100 )
UNION ALL ( SELECT <fields> FROM Messages1 order by ts limit 100 )
Best regards
Jarek
--
SQLAlchemy -
The Python SQL Toolkit and Object Relational Mapper
http://www.sqlalchemy.org/
To post example code, please provide an MCVE: Minimal, Complete, and Verifiable
Example. See http://stackoverflow.com/help/mcve for a full description.
---
You received this message because you are subscribed to the Google Groups
"sqlalchemy" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to sqlalchemy+unsubscr...@googlegroups.com.
To post to this group, send email to sqlalchemy@googlegroups.com.
Visit this group at https://groups.google.com/group/sqlalchemy.
For more options, visit https://groups.google.com/d/optout.
