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 tab
   Function startsWithCaseInsensitiveUTF8 (children 1)
    ExpressionList (children 2)
     Identifier S1
     Identifier S1
