SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Function count (children 1)
     ExpressionList (children 1)
      Identifier db.name
   TablesInSelectQuery (children 2)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.tables (alias t)
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      TableIdentifier system.databases (alias db)
     TableJoin (children 1)
      Function equals (children 1)
       ExpressionList (children 2)
        Identifier t.database
        Identifier db.name
   Function equals (children 1)
    ExpressionList (children 2)
     Identifier t.name
     Literal \'one\'
