CreateQuery test_in (children 3)
 Identifier test_in
 Columns definition (children 1)
  ExpressionList (children 1)
   ColumnDeclaration a (children 1)
    DataType LowCardinality (children 1)
     ExpressionList (children 1)
      DataType String
 Storage definition (children 2)
  Function MergeTree
  Identifier a
