mapping - scala slick 2.0.2 cannot automatic map to custom class -
i'm starting play slick , can't figure out how results of query mapped on custom case class. here's code:
package main.scala.model.tree import scala.slick.driver.h2driver.simple._ case class slicknode(id : long, parentid : long, statestring : string) extends abstractnode{} object slicknode { val nodes = tablequery[slicknodes] def findbyid(x : long) : slicknode = nodes.filter(_.id == x).first def findbyparentid(x : long) : iterable[slicknode] = nodes.filter(_.parentid == x).list } class slicknodes(tag: tag) extends table[(long, long, string)](tag, "nodes") { def id = column[long]("node_id", o.primarykey, o.autoinc) def parentid = column[long]("parent") def statestring = column[string]("state") def * = (id, parentid, statestring) <> ((slicknode.apply _).tupled , slicknode.unapply) } what expected automatic conversion (long, long, string) slicknode stated in * definition. missing something? thank in advance. kind regards
********* edit ********* think problem deeper in code. when try compile error:
[error] no matching shape found. [error] slick not know how map given types. [error] possible causes: t in table[t] not match * projection. or use unsupported type in query (e.g. scala list). [error] required level: scala.slick.lifted.shapelevel.flat [error] source type: scala.slick.lifted.mappedprojection[main.scala.model.tree.slicknode,(long, long, string)] [error] unpacked type: (long, long, string) [error] packed type: [error] def * = (id, parentid, statestring) <> ((slicknode.apply _).tupled , slicknode.unapply) [error] ^
the problem extending table of triple, not table of slicknoderow:
class abstractnode case class slicknoderow(id : long, parentid : long, statestring : string) extends abstractnode object slicknode { val nodes = tablequery[slicknodes] def findbyid(x : long)(implicit s: session): option[slicknodes#tableelementtype] = nodes.filter(_.id === x).firstoption def findbyparentid(x : long) : iterable[slicknoderow] = nodes.filter(_.parentid == x).list } class slicknodes(tag: tag) extends table[slicknoderow](tag, "nodes") { * here def id = column[long]("node_id", o.primarykey, o.autoinc) def parentid = column[long]("parent") def statestring = column[string]("state") def * = (id, parentid, statestring) <> ((slicknoderow.apply _).tupled , slicknoderow.unapply) } and projections function doesn't know how map triple slicknoderow case class. if want return triple code should this:
class suppliers(tag: tag) extends table[(int, string, string)](tag, "suppliers") { def id = column[int]("sup_id", o.primarykey) def name = column[string]("sup_name") def street = column[string]("street") def * = (id, name, street) } val suppliers = tablequery[suppliers] as shown here, projection doesn't return case class, triple instead. write projection method in way return slicknoderow triple, i'm not sure though.
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