Scala UDF 처리기의 예¶

CREATE OR REPLACE FUNCTION echo_varchar(x VARCHAR)
  RETURNS VARCHAR
  LANGUAGE SCALA
  CALLED ON NULL INPUT
  RUNTIME_VERSION = 2.12
  HANDLER='Echo.echoVarchar'
  AS
  $$
  class Echo {
    def echoVarchar(x : String): String = {
      return x
    }
  }
  $$;

CREATE OR REPLACE FUNCTION return_a_null()
  RETURNS VARCHAR
  LANGUAGE SCALA
  RUNTIME_VERSION = 2.12
  HANDLER='TemporaryTestLibrary.returnNull'
  AS
  $$
  class TemporaryTestLibrary {
    def returnNull(): String = {
      return null
    }
  }
  $$;

CREATE OR REPLACE FUNCTION extract_from_object(x OBJECT, key VARCHAR)
  RETURNS VARIANT
  LANGUAGE SCALA
  RUNTIME_VERSION = 2.12
  HANDLER='VariantLibrary.extract'
  AS
  $$
  import scala.collection.immutable.Map

  class VariantLibrary {
    def extract(m: Map[String, String], key: String): String = {
      return m(key)
    }
  }
  $$;

CREATE OR REPLACE FUNCTION generate_greeting(greeting_words ARRAY)
  RETURNS VARCHAR
  LANGUAGE SCALA
  RUNTIME_VERSION = 2.12
  HANDLER='StringHandler.handleStrings'
  AS
  $$
  class StringHandler {
    def handleStrings(strings: Array[String]): String = {
      return concatenate(strings)
    }
    private def concatenate(strings: Array[String]): String = {
      var concatenated : String = ""
      for (newString <- strings)  {
          concatenated = concatenated + " " + newString
      }
      return concatenated
    }
  }
  $$;

CREATE OR REPLACE FUNCTION sum_total_sales_snowflake_file(file STRING)
  RETURNS INTEGER
  LANGUAGE SCALA
  RUNTIME_VERSION = 2.12
  PACKAGES=('com.snowflake:snowpark:latest')
  HANDLER='SalesSum.sumTotalSales'
  AS
  $$
  import java.io.InputStream
  import java.io.IOException
  import java.nio.charset.StandardCharsets
  import com.snowflake.snowpark_java.types.SnowflakeFile

  object SalesSum {
    @throws(classOf[IOException])
    def sumTotalSales(filePath: String): Int = {
      var total = -1

      // Use a SnowflakeFile instance to read sales data from a stage.
      val file = SnowflakeFile.newInstance(filePath)
      val stream = file.getInputStream()
      val contents = new String(stream.readAllBytes(), StandardCharsets.UTF_8)

      // Omitted for brevity: code to retrieve sales data from JSON and assign it to the total variable.

      return total
    }
  }
  $$;

CREATE OR REPLACE FUNCTION sum_total_sales_input_stream(file STRING)
  RETURNS NUMBER
  LANGUAGE SCALA
  RUNTIME_VERSION = 2.12
  HANDLER = 'SalesSum.sumTotalSales'
  PACKAGES = ('com.snowflake:snowpark:latest')
  AS $$
  import com.snowflake.snowpark.types.Variant
  import java.io.InputStream
  import java.io.IOException
  import java.nio.charset.StandardCharsets
  object SalesSum {
    @throws(classOf[IOException])
    def sumTotalSales(stream: InputStream): Int = {
      val total = -1
      val contents = new String(stream.readAllBytes(), StandardCharsets.UTF_8)

      // Omitted for brevity: code to retrieve sales data from JSON and assign it to the total variable.

      return total
    }
  }
  $$;