CreateQuery test_string (children 3)
 Identifier test_string
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration c1 (children 1)
    DataType String
   ColumnDeclaration c2 (children 1)
    DataType String
 Storage definition (children 2)
  Function MergeTree
  Identifier c1
