CreateQuery src (children 3)
 Identifier src
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration s (children 1)
    DataType String
   ColumnDeclaration x (children 2)
    DataType String
    Literal \'a\'
 Storage definition (children 3)
  Function MergeTree (children 1)
   ExpressionList
  Function tuple (children 1)
   ExpressionList
  Identifier s
