Hi! I have got, 3 tables in a Oracle database. I build the connection and everything. :-) When I generate a query from one table it is fast, really fast. But I created another query I use 3 tables, but only two is neccesseary. The "*Q*" connected the "*P*" and the "*C*" (one (*Q*) to many (*P*, *C*)), "*P*" and "*C*" haven't got connection. The query is something like this: query_list = s.query(Q.id, C.mol_id, C.id, C.pc, C.poz, C.rown, C.col, C. data1, C.data2, C.data3, C.data4, P.file, P.txtfile, P.date, P.mean, P.sd, P .nmean, P.nsd, P.valid).join(P).join(C).filter(and_(P.ca_id == 13, C.pc != '!!!!!!!!', P.valid == 1, )).all()
I have got two problems: 1. Running time these script is 13-6 minutes! (yes, miniutes) I printed to the screen. There is any (much) faster solution? (rows number in the end 20000-100000 - depends the parameters) 2. Can I skip somehow the "Q" table columns from the query, or at least from the returned datas? The others is necessary columns. (bonus) 3. If, I send Pandas dataframe or Numpy matrix, or json dataformat and read these data is faster? Any idea for faster method? best, Attila -- 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.