why function will be invalid after many times of use?

From: <r_q_d_at_rocketmail.com>
Date: Sat, 11 Sep 1999 11:59:40 GMT
Message-ID: <7rdg7a$1o5$1@nnrp1.deja.com>

I have a table "FIELD_DICT" AND STORED FUNCTION "GET_FIELD_DICT_NAME" as below:
SQL> desc field_dict

 列名                          可空值否   类型
 ------------------------------- -------- ----
 TABLE_NAME                               VARCHAR2(30)
 FIELD_NAME                               VARCHAR2(30)
 FIELD_VALUE                              VARCHAR2(30)
 FIELD_MEAN                               VARCHAR2(30)
 STATUS                                   VARCHAR2(2)
 UPDATE_DATE                              DATE
 OPERATOR                                 VARCHAR2(10)
 REMARK                                   VARCHAR2(20)

SQL> desc get_field_dict_name
FUNCTION get_field_dict_name RETURNS VARCHAR2

 变元名称                       类型                    In/Out内设?
 ------------------------------ ----------------------- ------ --------
 IN_TABLE_NAME                  VARCHAR2                IN
 IN_FIELD_NAME                  VARCHAR2                IN
 IN_FIELD_VALUE                 VARCHAR2                IN

CREATE OR REPLACE
FUNCTION GET_FIELD_DICT_NAME(

   IN_TABLE_NAME IN VARCHAR2,
   IN_FIELD_NAME IN VARCHAR2,
   IN_FIELD_VALUE IN VARCHAR2 ) RETURN VARCHAR2 AS

   T_NAME VARCHAR2(250);
BEGIN
   select FIELD_MEAN
   into T_NAME
   from field_dict

   where table_name=in_table_name
     AND FIELD_NAME=in_field_name
     AND FIELD_VALUE=in_field_value
     AND ROWNUM=1;

   RETURN T_NAME;
EXCEPTION
   WHEN OTHERS THEN
      RETURN NULL;
END;
/

the function is called very frequency. I don't why after some days,this function will be invalid. and after I recompile it, all will be ok. Do any expert know why? My Oracle version is oracle 7.3 for WindowsNt

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Share what you know. Learn what you don't. Received on Sat Sep 11 1999 - 06:59:40 CDT