First Free Numbers (tcmcs0150m000)

Use this session to maintain the series defined for the Number Group shown at the top of the session.

Use the Group menu or the Group buttons to list the series of another number group. Choose on the Group menu to enter the series of a new number group.

You can add and remove series, specify the starting number, and block a series for use. You cannot change a series code.

Note: 

If a series is used, you cannot delete it. A series is used if it is defined for a type of record, regardless whether a number is actually generated. For example, if, in the Freight Order Control Parameters (fmfoc0100m000) session, series SLS is defined as the series for freight orders originating from sales orders, series SLS is used, even if no freight order has yet been generated for this series.

If you have started this session by zooming, you can only find and select a record.

Performance aspects

The settings in this session could affect system performance and database growth. For more information, refer to First free numbers.

Field Information

Number Group

number group

Series

The series code.

Allowed values

The series code must have the same number of characters as defined for this number group's series length in the Number Groups (tcmcs0151m000) session.

If the number group is dedicated to a specific use, the series code must be unique in the number groups dedicated to the same type of use.

Note: After saving the current session's data, you cannot change the Series field.

First Free Number

To improve the performance of sessions in which new order numbers are assigned, you can define a cache size for a series. The cache size is the number of new series numbers that LN generates at once. If there are series numbers in cache, users do not have to wait while LN generates and checks the next series numbers.

Allowed values

  • Cache size = 0

    No caching is applied. If you request a new number, the number is only committed after the transaction to which the number applies is completed.

    Disadvantage: The number series is locked during the transaction. Other users cannot request a new number from the same series until the transaction is completed.

    Advantage: No numbering gaps.

    Use a cache size of 0 if number gaps are not allowed. Preferably, request a new number close to the end of a transation to reduce locking time. In high volume implementations, a cache size of 0 may cause performance and locking issues.

  • Cache size = 1

    If you request a new number, the number is committed immediately, even if the transaction to which the number applies is not yet completed.

    Disadvantage: Numbering gaps may occur if a transaction is not finished.

    Advantage: The number series is locked for only a short time, which improves performance.

    A cache size of 1 is the default value for number series. In this way, performance and locking issues in high volume implementations are avoided as much as possible.

  • Cache size > 1

    The value of the cache size indicates how many new numbers are requested at once. The numbers are committed immediately, even if transactions are not yet completed.

    Disadvantage: Large numbering gaps may occur if more than one transaction is unfinished.

    Advantage: The number series is locked for only a short time. Furthermore, for all numbers that are requested, the number series needs to be updated only once, which improves performance.

    A cache size larger than 1 is only recommended if a cache size of 1 does not solve locking issues sufficiently.

Note: If the series is already in use, you cannot change the First Free Number field to a lower value.

First Free Number Cache Size

To improve the performance of sessions in which new order numbers are assigned, you can define a cache size for a series. The cache size is the number of new series numbers that LN generates and puts in the user's cache. The users do not have to wait while LN generates and checks the next series numbers.

If you use the first free numbers cache, the order numbers can be nonsequential; the numbers that are still in the user's cache are lost when the user logs off.

If you do not want to use the first free numbers cache, you must set the cache size to zero.

Series Blocked for Input

If this check box is selected, you cannot use the series. If you block a series, you must select another series for the type of orders or other elements to which the series is assigned.

Note: You can clear the check box to resume using a series.
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