SOLR-11488 is there so we formalize what we intend here. For instance, at one point we discovered that you could have an alias pointing to collection1,collection2 then delete collection2 say. Solr was happy in that configuration but it made no sense. See SOLR-11218.
So I don't know what the eventual resolution will be... In terms of why one would want an alias and collection to have the same name, a common recommendation is to completely re-index when making schema changes. By being able to create an alias with the same name as a collection, you can do that reindexing and atomically switch over without affecting the rest of your code or having any service interruption. So it looks like this: create a new_collection and index to it create an alias old_collection->new_collection delete old_collection and there's no service interruption. At very best if you couldn't create an alias with the same name as your collection, you'd have to create new_collection and index to it. Shut down all your apps delete old_collection create alias old_collection->new_collection bring all your apps back up. or create new_collection and index to it create an alias->new_collection rewrite all your apps to use the alias when they were all re-written, then delete old_collection. So it is convenient I think. We haven't moved forward on SOLR-11488 yet. SOLR-11218 beefed up some testing also so we don't inadvertently break things. Best, Erick On Fri, Jan 19, 2018 at 3:06 PM, Webster Homer <webster.ho...@sial.com> wrote: > It seems like a useful feature, especially for migrating from standalone to > solrcloud, at least if the precedence of alias to collection is defined and > enforced. > > On Fri, Jan 19, 2018 at 5:01 PM, Shawn Heisey <apa...@elyograg.org> wrote: > >> On 1/19/2018 3:53 PM, Webster Homer wrote: >> >>> I created the alias with an existing collection name because our code base >>> which was created with stand alone solr was a pain to change. I did test >>> that the alias took precedence over the collection, when I did a search. >>> >> >> The ability to create aliases and collections with the same name is viewed >> as a bug by some, and probably will be removed in a future version. >> >> https://issues.apache.org/jira/browse/SOLR-11488 >> >> It doesn't really make sense to have an alias with the same name as a >> collection, and the behavior is probably undefined. >> >> Thanks, >> Shawn >> > > -- > > > This message and any attachment are confidential and may be privileged or > otherwise protected from disclosure. If you are not the intended recipient, > you must not copy this message or attachment or disclose the contents to > any other person. If you have received this transmission in error, please > notify the sender immediately and delete the message and any attachment > from your system. Merck KGaA, Darmstadt, Germany and any of its > subsidiaries do not accept liability for any omissions or errors in this > message which may arise as a result of E-Mail-transmission or for damages > resulting from any unauthorized changes of the content of this message and > any attachment thereto. Merck KGaA, Darmstadt, Germany and any of its > subsidiaries do not guarantee that this message is free of viruses and does > not accept liability for any damages caused by any virus transmitted > therewith. > > Click http://www.emdgroup.com/disclaimer to access the German, French, > Spanish and Portuguese versions of this disclaimer.
