The function of an ORACLE long type into VARCHAR2

Do not know who originally wrote the function, take over to record, may use later.

* * Where In_rowid is a row id,in_owner the account name for the database, In_table_name is the database table name, in_column a long type of table field name for the database * *

CREATE OR REPLACE FUNCTION long_to_char (in_rowid rowid,in_owner 
varchar,in_table_name varchar,in_column varchar2) return 
varchar as 
text_c1 varchar2 (32767); 
Sql_cur varchar2 (); 
-- 
begin 
  Sql_cur: = ' SELECT ' | | in_column| | ' from 
' | | in_owner| | '. ' | | in_table_name| | ' Where rowID = 
' | | Chr (39) | | in_rowid| | Chr (); 
  Dbms_output.put_line (sql_cur); 
  Execute immediate sql_cur into TEXT_C1; 

  TEXT_C1: = substr (TEXT_C1, 1, 4000); 
  return TEXT_C1;  
End;