Had a bit of struggle to get this to work, logging the solution here so that it will be helpful to someone else. I am using Scala 2.9.1 and mybatis-scala-core 1.0.0.
val findOpenGroups = new SelectListBy[GroupIds,Group] {
def xsql = SELECT h.xxxxxx AS id,
h.xxxxxx AS launchedDate
FROM USA_xxxx_xxxx_xxxx h
WHERE h.new_status = 'Open'
AND h.id IN
<foreach item="item" collection="ids" open="(" separator="," close=")">
{"#{item}"}
</foreach>
}
GroupIds is a simple class, just make sure you are using the java.util.List.
class GroupIds(val ids:java.util.List[Int]){}
UPDATE
Frank Martínez pointed out to me that you can also do {"item" ?} instead of {"#{item}"} but you will need to import org.mybatis.scala.mapping.Binding._ Thanks Frank.
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Thanks for the tip. I was struggling to find out to do this using scala-mybatis and your article was exactly what I needed.