Modeling a Lifecycle

To correctly model a lifecycle you must define the lifecycle and its phases, and then associate your tables to it.

  1. Create a lifecycle in any of the following ways:

    • Select Model > Lifecycles (or Database > Data Lifecycle Management > List of Lifecycles) to access the List of Lifecycles, and click the Add a Row tool.

    • Right-click the model in the Browser, and select New > Lifecycle. Note that lifecycles can only be created at the model level and not within packages.

  2. Click the Properties tool to open the lifecycle property sheet, specify a name for the lifecycle and then select the policy type:
    • Age-based - Data moves through the lifecycle in named partitions, based on the time since the data was created. Specify a start date, along with the total retention period (the length of time covered by the lifecycle) and the partition range (the length of time covered by each partition).
    • Access-based - Tables move through the lifecycle based on the time since the table was last accessed. Specify a total retention period, which is treated as the minimum total period of time that a table's data must remain in the lifecycle.
  3. Click the Phases tab, and create as many phases as you need. Lifecycles often contain three phases to manage the movement of data from high performance, through nearline, to historical storage.
  4. Select each phase in turn and click the Properties tool to open its property sheet (see Phase Properties). Specify a name, retention period (or, for access-based lifecycles, idle period) and tablespace to represent the physical storage in which the data is stored during this phase.

    For age-based lifecycles, you can assign data from an external database to the first phase of your lifecycle. At the end of the first phase, the data will be loaded to your warehouse database. For more information, see Archiving Data From External Databases.

  5. Open the property sheet for each of your tablespaces (see Tablespace and Storage Properties) and enter any appropriate properties, including a value for the cost per GB to be used when calculating cost savings.
  6. Returning to the lifecycle property sheet, click the Tables tab and select the tables you want to associate with the lifecycle. For each table, specify the start date on which you want it to become subject to the lifecycle, and enter an estimate for the initial number of rows and a percentage growth rate to permit the calculation of cost savings.
  7. [age-based lifecycles] You must, for each table, specify a column with a date datatype as the partition key used to determine to which partition a row must be assigned. The partition key can be assigned in the Tables tab of the lifecycle property sheet or on the Sybase IQ tab of the table property sheets.
  8. [optional] You can, at any time, select one or more tables in the list and click the Estimate Cost Savings tool to estimate the savings to be accrued for them by the timely transfer of data to cheaper storage. You can view the detail of the cost savings by year on the Lifecyle tab of each table property sheet (see Table Properties).
    Note: If you intend to model multiple lifecycles, and/or want to confirm that all of your tables are associated with a lifecycle, you may find it useful to visualize these associations in the form of a dependency matrix. To view the Lifecycle/Table Matrix, select Database > Data Lifecycle Management > Lifecycle/Table Matrix.
Parent topic: Lifecycles (PDM)