Default Value for NEXT (SAP Library - SAP Database Guide: Oracle (BC-DB-ORA-DBA))

Default Value for NEXT

Definition

SAPDBA for Oracle recommends a default value for the NEXT parameter when you do one of the following:

Reorganize a table

Export a table

Change the storage parameters of a table

For more information about the NEXT parameter, see Storage Parameters.

Use

You can influence the calculation of the default value for extent parameter NEXT with the option Use ABAP Dic. for NEXT. The basis for calculating the NEXT parameters are the tables DD09L and TGORA / IGORA in the ABAP dictionary.

SAPDBA calculates a default value for the NEXT extent size as follows:

Use ABAP Dic. for NEXT: yes

The new value for NEXT is calculated as the maximum of the following values:

An SAP object is assigned a size category from table DD09L . The NEXT value is determined from table TGORA / IGORA based on that category. If the table does not have a category assigned in DD09L , this does not apply.

Current NEXT value

10% of the total allocated space

SAPDBA compares the calculated maximum value with the values for the extent size in TGORA / IGORA . SAPDBA generally chooses the next bigger value found in TGORA / IGORA as the new NEXT value except if:

The calculated maximum differs from the next smaller value of TGORA / IGORA by less than 5 Oracle blocks.

In this case, SAPDBA takes the smaller value. However, NEXT values that are larger than the largest TGORA / IGORA value are not reduced.

TGORA / IGORA does not exist.

In this case, SAPDBA uses internal default values which correspond to the values in TGORA / IGORA (see "NEXT Values in TGORA/IGORA" below).

Use ABAP Dic. for NEXT: no

SAPDBA does not use DD09L and TGORA / IGORA from the ABAP dictionary to derive the default value of NEXT . Instead, SAPDBA determines the maximum of the following two values:

Current value for NEXT

10% of the total allocated space

Structure

Defining the NEXT values to correspond to the permanently assigned values in the TGORA / IGORA tables, as shown below, results in less wasted space in the tablespace. If the extent values are defined using a size category assigned in the ABAP Dictionary – see Specification of SAP Tables in the ABAP Dictionary – incorrectly defined values can be easily corrected in the database.

NEXT Values in TGORA/IGORA

Size category	NEXT value for table (KB)	NEXT value for indexes (KB)
0	16	16
1	160	80
2	640	160
3	2560	640
4	10240	2560
5	20480	5120
6	40960	10240
7	81920	20480
8	163840	40960
9	327680	81920
10	655360	163840
11	1310720	327680
12	2621440	655360
13	5242880	1310720
14	10485760	2621440

You can change this distribution manually, but note the following:

Tables of size category 14 can reach a size of about 1000 GB and indexes a size of 250 GB for 100 assigned extents with the current default values. Therefore, consider carefully whether such large values are really required.

The extent values (except for category 0) are rounded to a multiple of 5* db_block_size (above table: to a multiple of 40 KB) in order to avoid additional Oracle rounding. If you change values or insert new ones, it is best to specify only the corresponding multiple.