Explain EXPLAIN SYNTAX (children 1)
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 3)
    ExpressionList (children 1)
     Function count (children 1)
      ExpressionList
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       TableIdentifier t_move_to_prewhere
    Function and (children 1)
     ExpressionList (children 4)
      Identifier a
      Identifier b
      Identifier c
      Function not (children 1)
       ExpressionList (children 1)
        Function ignore (children 1)
         ExpressionList (children 1)
          Identifier fat_string
