anchor.diff:  gremlin> :install com.datastax.cassandra cassandra-driver-core 2.1.9
   ==>Loaded: [com.datastax.cassandra, cassandra-driver-core, 2.1.9]
   gremlin> import com.datastax.driver.core.*
  -==>groovy.grape.Grape, org.apache.commons.configuration.*, ... java.time.Year, com.datastax.driver.core.*
  +==>groovy.grape.Grape, org.apache.commons.configuration.*, ..., com.datastax.driver.core.*
  +gremlin> import static com.datastax.driver.core.querybuilder.QueryBuilder.*
  +==>groovy.grape.Grape, org.apache.commons.configuration.*, ..., static com.datastax.driver.core.querybuilder.QueryBuilder.*
   gremlin> cluster = com.datastax.driver.core.Cluster.builder().addContactPoint("localhost").build()
   ==>com.datastax.driver.core.Cluster@3e1624c7
   gremlin> session = cluster.connect()
  
positive.code: gremlin>       select("person","year","location").by("name").by().by().
  gremlin>       sideEffect{
  gremlin>         def row = it.get()
  gremlin>         session.execute("INSERT INTO locations(name, location, year) VALUES ('${row.person}', '${row.location}', ${row.year});")
  gremlin>       }.iterate()
  gremlin> session.execute("SELECT * FROM locations")
  ==>Row[daniel, 2004, kaiserslautern]
  ==>Row[daniel, 2005, kaiserslautern]
  ==>Row[daniel, 2006, aachen]
  
negative.code: ...
  ==>Row[stephen, 2015, purcellville]
  ==>Row[stephen, 2016, purcellville]
  ----
  
  [[def-usage]]
  