Optimized query is empty when database is open and query uses a variable

On Wed, Oct 14, 2015 at 9:48 PM, Amanda Galtman <Amanda.Galtman at mathworks.com> wrote: > Hi, > > > > When I run the following query with BaseX 8.2.3 or 8.3, and I have a certain > database open, the optimized query is empty, so there are no results. > > > > let $x := 'x' > > let $doc := <root><el attr="x;y"/></root> > > return $doc//el[contains(@attr,$x)] > > > > This seems like a bug. If I close the database (which is not even being > referenced in this query), open a different database, or replace $x in the > last line with the literal string value, ‘x’, then I get the result I > expect. The database that exhibits the problem and the database that doesn’t > exhibit the problem differ in the kinds of XML files in them and the indexes > that are available for them. > > > > Does anyone know why the open database should affect the result of a query > that doesn’t reference the database? > > > > Thanks, > > Amanda

> -----Original Message----- > From: Christian Grün [mailto:christian.gruen at gmail.com] > Sent: Wednesday, October 14, 2015 3:58 PM > To: Amanda Galtman <Amanda.Galtman at mathworks.com> > Cc: basex-talk at mailman.uni-konstanz.de > Subject: Re: [basex-talk] Optimized query is empty when database is open > and query uses a variable > > Hi Amanda, > > You are completely right. It seems that the database statistics of a currently > opened database are utilized to optimize the path in your query. I have > added a GitHub issue [1], it should be fixed soon. > > Thanks, > Christian > > [1] https://github.com/BaseXdb/basex/issues/1202 > > > > > On Wed, Oct 14, 2015 at 9:48 PM, Amanda Galtman > <Amanda.Galtman at mathworks.com> wrote: > > Hi, > > > > > > > > When I run the following query with BaseX 8.2.3 or 8.3, and I have a > > certain database open, the optimized query is empty, so there are no > results. > > > > > > > > let $x := 'x' > > > > let $doc := <root><el attr="x;y"/></root> > > > > return $doc//el[contains(@attr,$x)] > > > > > > > > This seems like a bug. If I close the database (which is not even > > being referenced in this query), open a different database, or replace > > $x in the last line with the literal string value, ‘x’, then I get the > > result I expect. The database that exhibits the problem and the > > database that doesn’t exhibit the problem differ in the kinds of XML > > files in them and the indexes that are available for them. > > > > > > > > Does anyone know why the open database should affect the result of a > > query that doesn’t reference the database? > > > > > > > > Thanks, > > > > Amanda

On Wed, Oct 14, 2015 at 10:06 PM, Amanda Galtman <Amanda.Galtman at mathworks.com> wrote: > Thanks, Christian! > > Amanda > > >> -----Original Message----- >> From: Christian Grün [mailto:christian.gruen at gmail.com] >> Sent: Wednesday, October 14, 2015 3:58 PM >> To: Amanda Galtman <Amanda.Galtman at mathworks.com> >> Cc: basex-talk at mailman.uni-konstanz.de >> Subject: Re: [basex-talk] Optimized query is empty when database is open >> and query uses a variable >> >> Hi Amanda, >> >> You are completely right. It seems that the database statistics of a currently >> opened database are utilized to optimize the path in your query. I have >> added a GitHub issue [1], it should be fixed soon. >> >> Thanks, >> Christian >> >> [1] https://github.com/BaseXdb/basex/issues/1202 >> >> >> >> >> On Wed, Oct 14, 2015 at 9:48 PM, Amanda Galtman >> <Amanda.Galtman at mathworks.com> wrote: >> > Hi, >> > >> > >> > >> > When I run the following query with BaseX 8.2.3 or 8.3, and I have a >> > certain database open, the optimized query is empty, so there are no >> results. >> > >> > >> > >> > let $x := 'x' >> > >> > let $doc := <root><el attr="x;y"/></root> >> > >> > return $doc//el[contains(@attr,$x)] >> > >> > >> > >> > This seems like a bug. If I close the database (which is not even >> > being referenced in this query), open a different database, or replace >> > $x in the last line with the literal string value, ‘x’, then I get the >> > result I expect. The database that exhibits the problem and the >> > database that doesn’t exhibit the problem differ in the kinds of XML >> > files in them and the indexes that are available for them. >> > >> > >> > >> > Does anyone know why the open database should affect the result of a >> > query that doesn’t reference the database? >> > >> > >> > >> > Thanks, >> > >> > Amanda