Locking in Supply Network Planning (SNP) 
When a user changes data in the system, the system must lock this data. This prevents other users from changing the same data simultaneously and causing data inconsistencies. This means that you can only change data in Supply Network Planning (SNP) that is not currently locked. If, for example, in interactive planning, you select data that has already been locked, the system shows this data in display mode.
You have understood the role and purpose of the following:
SNP aggregates and planning objects
For more information, see Aggregates and Planning Objects.
SNP master data and time series management
For more information, see Maintaining SNP Master Data and Time Series.
To use the administration lock and the enhanced planning object lock, in Customizing for SAP Advanced Planning and Optimization, choose . In the TS: Enh. Locking (Time Series: Enhanced Locking) field, choose Active.
Supply Network Planning uses the following locking methods:
Planning object lock
SAP liveCache lock
Administration lock
Master data queue lock
As in Demand Planning (DP), the planning object lock and SAP liveCache lock serve the same purpose, they differ only in the accuracy of the lock. Moreover, these locking methods are used exclusively. The administration lock and the master data queue lock serve different purposes and can be used together with planning object locks or SAP liveCache locks.
The enhanced locking improves locking in SNP in the following ways:
You can perform interactive planning and planning area initialization in delta mode at the same time.
The enhanced planning object lock and administration lock help to prevent the creation of master data or time series inconsistencies when administrative and planning processes are performed simultaneously.
The planning object lock prevents simultaneous changes of data (time series or order quantities) for SNP planning objects. Planning objects are locked when a user loads them in interactive planning in change mode. A special case of planning object lock is the version lock; in this case all planning objects in the given version are locked. The system sets the version lock for the following master data and time series management processes:
Initialization of planning areas (except in delta mode)
De-initialization of planning areas
Consistency check, if you have selected the Lock Planning Version checkbox
SNP time series reorganization, if you have selected the Lock Planning Version checkbox
Planning area change
Note
The delta mode of planning area initialization is only available if the enhanced locking is activated, and it does not lock the planning version.
Similarly as in Demand Planning, the SAP liveCache lock is a more accurate locking method than planning object lock. SNP uses it for the same purpose and in the same way as the planning object lock.
The administration lock excludes the possibility that SNP time series administration processes run simultaneously for the same planning area and planning version combination. The administration lock always locks the whole version, but is used only by administration processes. This means that it does not prohibit planning activities on the given planning version. The system uses the administration lock only for SNP planning areas and only if you have activated enhanced locking. The system sets the administration lock for the following processes:
Initialization of planning area (also in delta mode)
De-initialization of planning area
Consistency check in repair mode (also in case you have not selected the Lock Planning Version checkbox)
SNP time series reorganization in repair mode (also in case you have not selected the Lock Planning Version checkbox)
Planning area change
The master data queue lock protects the consistency of SNP master data queues of level 1 and 2, while a queue update or an administrative process is running. The system uses the master data queue lock for SNP processes, and only if enhanced locking is activated. The system sets the master data queue lock in the following cases:
A master data queue update process is running (which can be initiated at the start of interactive planning or at the start of background planning processes)
SNP master data update is running
Planning area initialization is running
If the master data queue lock is set, interactive planning and background planning processes skip the master data queue update. However, planning area initialization does not start until it can acquire a master data queue lock. If the master data queue is locked, the system waits for the time you specified in Customizing for Advanced Planning and Optimization, under , in the TS: Max Waittime field. If the queue is still locked after the time has passed, planning area initialization terminates with an error message.
You can display planning object and SAP liveCache lock entries in interactive planning. To do so, choose . In addition, you can display the lock situation for all system objects. To do so, on the SAP Easy Access screen, choose . SNP locking methods use the following tables:
Locking Method |
Lock table |
|---|---|
Planning object lock |
/SAPAPO/DM_PAREA_LOCK |
Administration lock |
/SAPAPO/DM_PAREA_LOCK3 |
Master data queue lock |
/SAPAPO/MSDP_PAR_T_LOCK |
Note
Lock tables are not regular transparent tables but structures.
If the system uses the SAP liveCache lock, the planning object lock contains only a generated ID representing the lock. To view the details of the lock, on the SAP Easy Access screen, choose , or .
To find out more about locking conflicts, you can enable the monitoring and logging of locks. For more information, see Lock Monitor for Supply Network Planning (SNP) and Demand Planning (DP).