Checking Storage Parameters (Oracle)
You should check whether there is enough freespace in the tablespaces in particular before transmitting mass data to the SAP system. You can use the Database Monitors to find out whether additional extents - if required for the amount of data to be transferred - can be allocated. When you perform a storage space analysis, you should also check the storage parameters.
To analyze the storage parameters:
From the main screen, choose Tools → Administration → ComputingCenter →Management System → Control → Performance Menu → Database → Tables / Indexes.
Alternatively, use transaction code DB02 .
Choose Detail analysis menu → Parameter changes.
You can now analyze the storage parameters for tablespaces or individual tables.
- Storage parameters for each tablespace
- Tablespaces section: Current sizes, Storage parameter
- Storage parameters for tables of a tablespace
- Tables and Indexes section: Detailed analysis(specify the tablespace), select the table, Analyze → Extents
- Tables and Indexessection: Detailed analysis(specify the tablespace), select the table, Analyze → Tables and its indexes, Storage parameter
- Storage parameters for a table
- Tables and Indexes section: Detailed analysis(specify the table), Analyze → Extents
- Tables and Indexes section: Detailed analysis(specify the table), Analyze → Tables and its indexes, Storage parameter
Storage Parameters
| Field | SQL Parameters | Meaning |
|---|---|---|
|
Pct. fre |
PCTFREE |
Percentage of memory of a data block that is kept free for possible changes to existing lines (default value is usually 10%). |
|
Pct. use |
PCTUSED |
When a data block is full (except for the space for PCTFREE), no more new lines are inserted in it. Lines can only be inserted in this block again when the percentage of used memory falls below the value of PCTUSED (default value is usually 40%). |
|
Init ext |
INITIAL |
Size of the first extent with which a table or index was created. |
|
Next ext |
NEXT |
Size of the next extent that is assigned should a new extent be required. |
|
Min Ext |
MINEXTENTS |
Initial number of extents when a table or index is created. |
|
Max Ext |
MAXEXTENTS |
Upper limit for the number of extents of a table or index (default value is usually 300). MAXEXTENTS is a "soft limit" for the number of extents that can be allocated in a tablespace. |
|
Pct. inc |
PCTINCREASE |
Percentage by which the size of the next extent is increased when each additional extent is assigned. SAP tables and indexes usually show a factor of zero. The size of the next extent remains constant, and as a result, problems with freespace are avoided. |
If you are importing new data to the system, you should in particular monitor the number of extents allocated for tables that are growing rapidly to avoid reaching the value for the MAXEXTENTS storage parameter.
New master records are to be imported to the system.
To estimate the amount of data to be transferred, determine the average size of the master records to be transferred and multiply it by the approximate number of the master records. Generally, the master records are in tablespace PSAPSTABD and the indexes are in PSAPSTABI.
Check whether the tablespace still has enough freespace with BR*Tools.
Then determine the total number of additional extents necessary for the data. To calculate this, divide the quantity of the data by the expected value in the column Next extent of a representative table.
You can use this information to estimate whether the tablespace must be extended, the NEXT parameter changed, or the MAXEXTENTS parameter increased for the tablespace.
For more information on how to modify tablespaces, see Space Management with BR*Tools
See also:
Checking for Full Tablespaces (Oracle)
Checking for Freespace Problems (Oracle)
Storage Management Errors (Oracle)
Problems with Maximum Number of Extents (Oracle)