HP 3000 Manuals HP 3000 Manuals
Changing a Data Item
In this section, the YIELD data item in the ORDERS database is changed to
type E. YIELD is changed from a type R to a type E, although the data
already is stored in IEEE data format. The length and security are also
changed.
Use the CHANGE ITEM command to change the data item YIELD in the ORDERS
database. Before changing the data item, the REVIEW ITEMS output looks
like this:
Itm No. Item Name Attrib Security
------------------------------------------
27 YIELD R2
NOTE Refer to Table 2-1 for information about data item type
conversions supported by DBChange Plus.
In the example below, the CHANGE ITEM command is used to change the data
item YIELD to type E. The length is changed to 4. Notice that the
special no-conversion option (!E) is used with YIELD to change just the
type and length, because the data is already stored in IEEE data format.
When restructuring takes place, the data is converted from E2 format to
E4 format. The security is also changed to allow write access for user
class 12. The DBCPLUS program displays messages confirming that the
changes are accepted.
>change item yield !e 4 (/12)
Change of item attributes accepted.
Change of item security accepted.
CAUTION If the data item length is changed to a smaller number than the
original data item length, the data may truncate or overflow the
new field.
Refer to "CHANGE ITEM" in chapter 3, "Revised Command Descriptions," for
a detailed description of the command syntax and parameters.
If you want to verify that the modifications to the data item YIELD are
in the change file, use the REVIEW ITEMS command. In the following
example, YIELD is the name of the data item to be reviewed. You can see
that the data item YIELD is now defined as a type E with a length of 4
and that security has been added.
>review items yield
REVIEW ITEMS:
Itm No. Item Name Attrib Security
------------------------------------------
27 YIELD E4 (/12)