Scala slick query where in list

Question

I am attempting to learn to use Slick to query MySQL. I have the following type of query working to get a single Visit object:

Q.query[(Int,Int), Visit](\"\"\"
          


        

Answer 1

If you have a complex query and the for comprehension mentioned above is not an option, you can do something like the following in Slick 3. But you need to make sure you validate the data in your list query parameter yourself to prevent SQL injection:

val locationCodes = "'" + List("loc1","loc2","loc3").mkString("','") + "'"
sql"""
  select * from visit where visitor = $visitor 
    and location_code in (#$locationCodes)
"""

The # in front of the variable reference disables the type validation and allows you to solve this without supplying a function for the implicit conversion of the list query parameter.