A block lines has item line_number. When a record is deleted,

line_number must be renumbered.

step 1：

Create your item handler procedures as follows:

PACKAGE BODY lines IS

line_number_seq number := 0;

PROCEDURE delete_row IS

BEGIN

line_number_seq := 0;

APP_RECORD.FOR_ALL_RECORDS(‘reseq_line_number’);

END delete_row;

END lines;

step 2：

Create a user–defined trigger RESEQ_LINE_NUMBER as follows:

lines.line_number_seq := lines.line_number_seq + 1;

:lines.line_number := lines.line_number_seq;

step 3：

Call your item handler procedures in:

Trigger: KEY–DELETE:

lines.line_number(’KEY–DELETE’);

以上是标准文档的东西，但是错就在第三步，正确的是：

Trigger:  KEY-DELREC :

delete_record;

lines.delete_row;