For example, I want to create the following query:
SELECT c.* FROM Coffees c WHERE c.name IN ('robusta', 'arabica')
My attempt failed:
val cnames = List("robusta", "arabica")
sql""" SELECT c.* FROM Coffees c WHERE c.name IN ${cnames} """
could not find implicit value for parameter pconv:
scala.slick.jdbc.SetParameter[List[String]]
Is it possible to somehow use in
clause in Slick
plain sql queries?
I don't see anything out of the box to handle this. You're best bet is probably something like this:
val cnames = List("robusta", "arabica").map("'" + _ + "'").mkString(",")
val query = sql""" SELECT c.* FROM Coffees c WHERE c.name IN (${cnames}) """
The type safe "lifted embedding" API supports this as well:
val ids = List(1,2,3)
val q = for {
f <- Foo if f.id inSet ids // ids is not bound
}
slick.typesafe.com/doc/1.0.1/api/index.html#scala.slick.lifted.ColumnExtensionMethods
Although it's not safe for SQL injection, you can use #$
interpolator:
val ids = idList.map("'" + _ + "'").mkString(",")
val q = sql"""select name from mytable where id in (#$ids)"""
There is a library that (among other things) introduces a binder for list properties to Slick's SQL interpolator: https://index.scala-lang.org/tarao/slick-jdbc-extension-scala/slick-jdbc-extension
Example code from the page:
import util.NonEmpty
def findAll(entryIds: Option[NonEmpty[Long]]): Seq[Entry] = entryIds match {
case Some(ids) => run { sql"""
| SELECT * FROM ${table}
| WHERE entry_id IN $ids
""".as[Entry] }
case None => Seq.empty
}
来源:https://stackoverflow.com/questions/17408444/is-it-possible-to-use-in-clause-in-plain-sql-slick