Path: csiph.com!usenet.pasdenom.info!weretis.net!feeder4.news.weretis.net!newsfeed.fsmpi.rwth-aachen.de!eternal-september.org!feeder.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Martin Gregorie Newsgroups: comp.lang.java.programmer Subject: Re: ORMs comparisons/complaints. Date: Fri, 3 Jan 2014 22:30:48 +0000 (UTC) Organization: A noiseless patient Spider Lines: 44 Message-ID: References: <%JGtu.29103$Wm1.26832@fx17.iad> <52c4d306$0$302$14726298@news.sunsite.dk> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Injection-Date: Fri, 3 Jan 2014 22:30:48 +0000 (UTC) Injection-Info: mx05.eternal-september.org; posting-host="e5160e2be48f1ea550cf61512446f525"; logging-data="15608"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18mjQq939J5usxcoapvmccNMcYuy+oO5rI=" User-Agent: Pan/0.139 (Sexual Chocolate; GIT bf56508 git://git.gnome.org/pan2) Cancel-Lock: sha1:TBk5u2OE8KhSI7GSEVk5ehwGA2I= Xref: csiph.com comp.lang.java.programmer:27221 On Fri, 03 Jan 2014 16:04:40 -0400, Arved Sandstrom wrote: > Martin, the SQL generated by Java ORMs is not hidden. Suitable logging > levels expose the generated SQL. If you distrust that logging there are > always DB profilers. Many/most ORMs are open source: when in doubt, > investigate the code...I've tweaked several Java ORMs after code > inspection. > I'd assumed that the ORM would be generating SQL, so its good to know that what it generates can be inspected. Not that I'm casting nasturtiums at ORMS, but I've seen some truly dreadful automatically generated SQL in the past (Sybase PowerBuilder, I'm looking at you), so I tend to be suspicious of auto-generated SQL. However, I was wondering whether there any performance problems could come from the way an ORM uses its generated SQL and what tools might be available to analyse them. > In my opinion the first and usually the best "tool" is simply the native > implementation spec. > Fair comment. > I do myself understand execution plans quite well, but not nearly as > well as a good DBA. In most consulting engagements that involve RDBMSs, > if performance issues get tricky I do not hesitate to talk to a resident > DBA: that's another great "tool". > I've had a fairly varied range of experience ranging from application implementation and design over a range of databases (IDMSX as well as relational) and languages and have also been both sysadmin and DBA on several OSen and DBMS, eventually realising that I was getting typecast as a DBA/DB designer and general DB performance tuner. At that point I had to take positive action to get back into systems development, but have never entirely left that skill set behind. This is why I'm curious about this area. ...just so's you know. -- martin@ | Martin Gregorie gregorie. | Essex, UK org |