MD5_HIDDEN Function

This function is used for lost update detection. Lost update detection ensures data integrity in applications where data can be accessed concurrently.

This function produces a hidden form field and includes 50 inputs. HTMLDB_ITEM.MD5_HIDDEN also produces an MD5 checksum using the Oracle database DBMS_OBFUSCATION_TOOLKIT:

UTL_RAW.CAST_TO_RAW(DBMS_OBFUSCATION_TOOLKIT.MD5())

An MD5 checksum provides data integrity through hashing and sequencing to ensure that data is not altered or stolen as it is transmitted over a network

Syntax

HTMLDB_ITEM.MD5_HIDDEN(
    p_idx       IN    NUMBER,
    p_value01   IN    VARCHAR2 DEFAULT,
    p_value02   IN    VARCHAR2 DEFAULT,
    p_value03   IN    VARCHAR2 DEFAULT,
    ...
    p_value50   IN    VARCHAR2 DEFAULT,
    p_col_sep   IN    VARCHAR2 DEFAULT)
    RETURN VARCHAR2;

Parameters

Table: MD5_HIDDEN Parameters describes the parameters available in the MD5_HIDDEN function.

MD5_HIDDEN Parameters

Parameter Description

Parameter	Description
`p_idx`	Indicates the form element to be generated. For example, 1 equals `F01` and 2 equals `F02`. Typically the `p_idx` parameter is constant for a given column
`p_value01` ... `p_value50`	Fifty available inputs. Parameters not supplied default to null
`p_col_sep`	String used to separate `p_value` inputs. Defaults to the pipe symbol (\|)

p_idx

Indicates the form element to be generated. For example, 1 equals F01 and 2 equals F02. Typically the p_idx parameter is constant for a given column

p_value01

...

p_value50

Fifty available inputs. Parameters not supplied default to null

p_col_sep

String used to separate p_value inputs. Defaults to the pipe symbol (|)

Example

The p_idx parameter specifies the FXX form element to be generated. In the following example, 7 generates F07. Also note that an HTML hidden form element will be generated.

SELECT HTMLDB_ITEM.MD5_HIDDEN(7,ename,job,sal), ename, job, sal FROM emp