Hello all, Hope you are fine and safe in these times! I can be easily considered as a novice in SQLAlchemy. I am trying to pull data from a MYSQL database from a table having around 20 columns and more than 10 million rows. The table is partitioned and indexed. I am using a complex query, having UNION of multiple sub-queries, in the format:
with cte1 as <subquery1>, cte2 as <subquery2>, .. select * from cte1 union all select * from cte2 ; The code demands it to be a dynamic query and number of sub-queries depends on the user input. For understanding purpose, I took a query having two sub-queries. So, when I passed the query to MySQL directly, it took very less time (around 0.016 seconds) but when I passed the same query through SQLAlchemy connector, it took around 600 seconds. I tried generating the query using only text clause in one approach and I also tried combination of .select(), .where() and .and_ query approach. However, both were taking a very long time. I am not sure what can be issue. It'll be great if I can get any pointers to reduce the time, preferably under 10 seconds! Thanks in advance! Regards, Saylee -- 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 view this discussion on the web visit https://groups.google.com/d/msgid/sqlalchemy/f7b03dcd-dd38-4df1-8719-a7902b1a39d4o%40googlegroups.com.
