CreateQuery tab (children 3)
 Identifier tab
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration haystack (children 1)
    DataType String
   ColumnDeclaration pattern (children 1)
    DataType String
 Storage definition (children 2)
  Function MergeTree (children 1)
   ExpressionList
  Identifier haystack
