HP OpenVMS Systems Documentation

HP COBOL
DBMS Database Programming Manual

Function

The GET statement moves the contents of the current database record of the run unit to your user work area.

record-name

names a subschema record type.

record-item

is a group or elementary data item in a subschema record type. Record-item may be qualified.

stment

is an imperative statement executed for an on error condition.

stment2

is an imperative statement executed for a not on error condition.

Syntax Rules

1. Each record-item must reference a data item in the same subschema record type.
2. If record-item is a group item, its subordinate group and elementary items cannot be referenced in the same GET statement.

General Rules

1. The GET statement references the current record of the run unit.
2. If you use the record-name option, or if you do not specify either the record-item or the record-name option, the DBCS makes a copy of the entire current record of the run unit available to the program in the user work area.
3. If you use the record-item option, only those items in the current record of the run unit are made available to the program in the user work area.
4. Any change made to the user work area does not affect the record in the database. You must execute a MODIFY and a COMMIT statement to make permanent changes to the database.
5. Use record-name to check that the record type of the current record is identical to the record type specified by record-name.
6. The GET statement has no effect on currency indicators.
7. If a database exception condition occurs during the execution of a GET statement, the DBCS places a database exception condition code in the special register DB-CONDITION (see Technical Note). This code identifies the condition.

Technical Note

GET statement execution can result in these DB-CONDITION database exception condition codes:

Additional References

• Section 2.2, on reserved words (database special registers)
• HP COBOL Reference Manual, Chapter 6, section on scope of statements
• Section 4.8.1, on database On Error condition
• USE statement

Examples

1. This example gets the current record of the run unit:

   GET.

2. This example gets a PART record only if it is the current record of the run unit:

   GET PART.

3. This example gets these items only if they are part of the current record of the run unit:

   GET PART_ID, PART_DESC.

Function

The KEEP statement inserts a database key value from a currency indicator or keeplist into a keeplist.

database-key-id

represents a database key identifier. References are made to a keeplist entry or a currency indicator according to the rules for Database Key Identifiers.

destination-keeplist

names a keeplist in the Subschema Section to receive the database key value.

stment

is an imperative statement executed for an on error condition.

stment2

is an imperative statement executed for a not on error condition.

General Rules

1. If database-key-id references a database key value in either a currency indicator or a keeplist, the DBCS:
   • Inserts that value as the last entry in destination-keeplist
   • Sets a lock on the associated record to prevent concurrent run units from accessing it
2. If the program does not specify database-key-id, the DBCS inserts the database key value of the current record of the run unit as the last entry of destination-keeplist.
3. The KEEP statement has no effect on currency indicators.
4. If a database exception condition occurs during the execution of a KEEP statement, the DBCS places a database exception condition code in the special register DB-CONDITION (see Technical Note). This code identifies the condition.

Technical Note

KEEP statement execution can result in the database exception conditions associated with the evaluation of the database key identifier.

Additional References

• Section 2.2, on reserved words (database special registers)
• Keeplist Description entry
• HP COBOL Reference Manual, Chapter 6, section on scope of statements
• Section 4.4, on database key identifiers
• Section 4.8.1, on database On Error condition
• USE statement

Examples

1. Currency indicator access
   • To insert the database key value of the current record of the run unit into KEEPLIST-A:

     KEEP CURRENT USING KEEPLIST-A.

   • To insert the database key value of the current record of the CLASS_PART set into KEEPLIST-B:

     KEEP CURRENT WITHIN CLASS_PART USING KEEPLIST-B.

   • To insert the database key value of the current record of the BUY realm into KEEPLIST-B:

     KEEP CURRENT WITHIN BUY USING KEEPLIST-B.

   • To insert the database key value of PART record into KEEPLIST-B:

     KEEP CURRENT WITHIN PART USING KEEPLIST-B.

2. Keeplist access
   • To insert the first keeplist entry from KEEPLIST-A as the last entry in KEEPLIST-B:

     KEEP FIRST WITHIN KEEPLIST-A USING KEEPLIST-B.

   • To insert the last keeplist entry in KEEPLIST-A as the last entry in KEEPLIST-B:

     KEEP LAST WITHIN KEEPLIST-A USING KEEPLIST-B.

   • To insert the fourth keeplist entry relative to the current position in KEEPLIST-A as the last entry in KEEPLIST-B:

     KEEP OFFSET 4 WITHIN KEEPLIST-A USING KEEPLIST-B.

Function

The MODIFY statement changes the contents of specified data items in a database record.

record-name

names a subschema record type.

record-item

is a group or elementary data item in a subschema record type. Record-item can be qualified.

set-name

names a subschema set type.

stment

is an imperative statement executed for an on error condition.

stment2

is an imperative statement executed for a not on error condition.

Syntax Rules

1. Each record-item must reference a data item in the same subschema record type.
2. If record-item is a group item, its subordinate group and elementary data items cannot be referenced as a record-item in the same MODIFY statement.
3. Use record-name to check that the current record of the run unit is a record type identical to the record-name record type.

General Rules

1. Changes are made to a database record by:
   • Locating the target record (FIND and GET, or FETCH)
   • Moving the new data to the data-name references in the user work area
   • Executing the MODIFY statement
2. The DBCS changes the contents of the entire database record:
   • If you specify record-name
   • If you specify neither record-name nor record-item
3. Using record-item limits the changes to the database record to only those items you specify.
4. If you modify any data item that is the sort key for that record's position in a sorted set, the DBCS automatically repositions the record in that set in accordance with the set-ordering criteria of the set type.
   If the value of the sort key is identical to another record of this type, and if duplicates are not allowed for this sorted set, the DBCS does not perform the MODIFY operation, and a database exception condition occurs.
5. Currency indicator update rules for record insertion and removal are as follows:
   • If the MODIFY statement removes a record from the current set, the currency indicator for that set points to the position in the set vacated by the record. (At this position the record is no longer accessible.)
   • If the MODIFY statement reinserts a record in a set in another location, the set currency indicator changes to point to the record in this new location.
   • If you do not include the RETAINING clause (see Section 4.9.1, RETAINING Clause), the currency indicator for the set is modified to the current record of the run unit.
6. The current record of the run unit must be in a realm in ready update mode and all records required by the DBCS to execute the MODIFY statement must be in realms in one of the appropriate READY modes.
7. The contents of the user work area (UWA) do not change after the successful or unsuccessful execution of a MODIFY statement.
8. If the execution of a MODIFY statement results in an exception condition, the record is not changed.
9. If a database exception condition occurs during the execution of a MODIFY statement, the DBCS places a database exception condition code in the special register DB-CONDITION (see Technical Notes). This code identifies the condition.