DISCONNECT

Purpose

Disconnects a record occurrence from a set occurrence in which it participates as a member.

Membership in the object set must be defined as OPTIONAL in the dialog's schema.

Syntax

►►─── DISCONNECT record-name FROM set-name ───┬────────────────────┬──── . ───►◄
                                              └─ error-expression ─┘

Parameters

record-name

Specifies the current occurrence of the named record to be disconnected.

Record-name must be known to the dialog's subschema.

FROM set-name

Specifies the set from which the current occurrence of the named record is to be disconnected.

Set-name must be known to the dialog's subschema and must be defined as optional.

error-expression

Specifies the status codes that are returned to the dialog.

Usage

Considerations

If autostatus is not in use, a dialog's error-status field indicates the outcome of a DISCONNECT command:

Status code	Meaning
0000	The request was executed successfully
1106	Currency was not established for the object record
1108	The specified record is not in the dialog's subschema
1109	The object record's area was not readied in an update usage mode
1110	The dialog's subschema specifies an access restriction that prohibits disconnecting the object record from the named set
1115	The DISCONNECT command cannot be executed because the object set is defined as mandatory
1121	An area other than the area of the object record was readied with an incorrect usage mode
1122	The object record is not currently a member of the specified set
1129	A run-unit deadlock condition occurred. DBMS aborted and rolled back the run unit. All resources associated with the task are released

Further Considerations

The DISCONNECT command cannot be used with native VSAM data sets because all such sets must be defined as mandatory automatic.
Before a DISCONNECT command can be executed, the following conditions must be satisfied:
- All areas affected either directly or indirectly by the DISCONNECT command must be readied in an update usage mode.
- The object record must be established as current of its record type.
After successful execution of a DISCONNECT command, the object record can no longer be accessed through the set for which membership was canceled.
A disconnected record can be accessed through any other sets in which it participates as a member or through its CALC key if it has a location mode of CALC.
A disconnected record is always accessible by means of an area search or through its database key.
A DISCONNECT command nullifies currency in the object set. However, the next of set and prior of set are maintained, enabling access to continue within the set.
A disconnected record becomes current of:
- The run unit
- Its record type
- Its area

Example

The statements in the following example establish an ITEM record as current of record type and disconnect the record from the PRODUCT-ITEM set:

MOVE 'P8' TO PROD-NUMBER.
FIND CALC PRODUCT.
FIND FIRST ITEM WITHIN PRODUCT-ITEM.
DISCONNECT ITEM FROM PRODUCT-ITEM.

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