As described in Limitations of the Database System, a table or an index has a software limit of 100 extents (parameter MAXEXTENTS) in the initial R/3 installation. If a table or an index reaches this limit, an extent overflow error occurs the next time an extent is requested.
In this case, you can increase the NEXT and/or MAXEXTENTS parameters, e.g. using the function Reorganization ® Alter/Show table or index storage parameters. MAXEXTENTS can be increased to a value lower than or equal to 505 extents (for a block size of 8 KB). Therefore, when you reach the soft limit for MAXEXTENTS, you should not perform a reorganization of the object or tablespace immediately. However, this procedure should only be used in an emergency. The table or index should be reorganized as soon as possible in order to reset the MAXEXTENTS size to the SAP standard value.
MAXEXTENTS is automatically reset to the SAPDBA default value when there is an import or a reorganization of the relevant object. This value is defaulted even when you use one of the options for changing storage parameters manually.
As of ORACLE 7.3, you can set MAXEXTENTS to ‘UNLIMITED’.
See also Changing Storage Parameters.
Measures to Avoid Reaching the MAXEXTENTS Value:
- You can prevent the number of extents from growing too quickly by promptly increasing the NEXT parameter (larger extents are then allocated). You should therefore regularly use the SAPDBA command line option sapdba -next. See Command Option -next.
If, despite the above considerations, a table still reaches a large number of extents, you can increase the MAXEXTENTS parameter (as described above) to allow more extents.
- Experienced database administrators can also influence the degree of occupancy of the data blocks by changing the parameters PCTFREE and PCTUSED. However, this is not normally necessary.
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