Improper use? Potential bug? Your feedback is welcome:
Sounds like a little bug indeed; I will check it tomorrow!
Contact: basex-talk@mailman.uni-konstanz.de Version: BaseX 7.9 Java: Oracle Corporation, 1.7.0_45 OS: Mac OS X, x86_64 Stack Trace: java.lang.NullPointerException at org.basex.query.value.item.Str.get(Str.java:49) at org.basex.query.func.FNDb.path(FNDb.java:489) at org.basex.query.func.FNDb.item(FNDb.java:128) at org.basex.query.expr.ParseExpr.iter(ParseExpr.java:45) at org.basex.query.func.FNDb.iter(FNDb.java:92) at org.basex.query.gflwor.GFLWOR$2.next(GFLWOR.java:78) at org.basex.query.MainModule$1.next(MainModule.java:98) at org.basex.core.cmd.AQuery.query(AQuery.java:91) at org.basex.core.cmd.XQuery.run(XQuery.java:22) at org.basex.core.Command.run(Command.java:329) at org.basex.core.Command.execute(Command.java:94) at org.basex.server.LocalSession.execute(LocalSession.java:121) at org.basex.server.Session.execute(Session.java:37) at org.basex.core.CLI.execute(CLI.java:106) at org.basex.BaseX.<init>(BaseX.java:123) at org.basex.BaseX.main(BaseX.java:42)
On Thu, Oct 30, 2014 at 5:54 AM, Christian Grün christian.gruen@gmail.com wrote:
Hi Mansi,
you have been close! It could work with the following query (I haven't tried it out, though):
_ get_query_result.xq ____________________
declare variable $n external; declare option output:item-separator "
";
let $aList := for $name in db:list() let $db := db:open($name) return xquery:eval($n, map { '': $db })
return distinct-values($aList) ______________________________________
In this code, I'm opening the database in the main loop, and I then bind it to the empty string. This way, the database will be the context of the query to be evaluated query, and you won't have to deal with bugs that arise from the concatenation of "db:open" and the query string.
- Can we assign dynamic values as a value to a map's key ?
- Can I map have more than one key, in query:eval ?
This is both possible. As you see in the following query, you'll again have to declare the variables that you want to bind. I agree this causes a lot of code, so we may simplify it again in a future version of BaseX: ______________________________________
let $n := "/a/b/c" for $db in db:list() let $query := "declare variable $db external; " || "db:open($db)" || $n return xquery:eval($query, map { 'db': $db, 'query': $n }) ______________________________________
Best, Christian
--
- Mansi