CreateQuery test (children 3)
 Identifier test
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration key (children 1)
    DataType UInt32
   ColumnDeclaration value (children 1)
    DataType String
 Storage definition (children 3)
  Function MergeTree (children 1)
   ExpressionList
  Identifier key
  Set