Hierarchy
⤷ CA-GTF-DRT (Application Component) Data Retention Tool
⤷ FTW1 (Package) Data Retention Tool
Basic Data
Data Element | TXW_X_ORDR |
Short Description | Flag: Use specified access sequence |
Data Type
Category of Dictionary Type | D | Domain |
Type of Object Referenced | No Information | |
Domain / Name of Reference Type | XFELD | |
Data Type | CHAR | Character String |
Length | 1 | |
Decimal Places | 0 | |
Output Length | 1 | |
Value Table |
Further Characteristics
Search Help: Name | ||
Search Help: Parameters | ||
Parameter ID | ||
Default Component name | ||
Change document | ||
No Input History | ||
Basic direction is set to LTR | ||
No BIDI Filtering |
Field Label
Length | Field Label | |
Short | 0 | |
Medium | 0 | |
Long | 0 | |
Heading | 0 |
Documentation
Definition
If the "Optimize access sequence" flag is selected, DART tries to optimize the order in which view segments are processed. In most cases, this will give good results.
However, there are cases when the optimization does not give the best possible result, leading to bad runtime performance. In such cases, manual selection of the segment order is a better option. Segments should be ordered so that the number of records that need to be read from a data file is as small as possible. Thus, segments should be ordered in accordance to how specific they make the selection.
To manually specify the order in which segments are processed, select the flag "Use specified access sequence" and enter "1" for the first segment to be processed, "2" for the second, and so on. The default sequence is the order in which the segments are listed in the view definition.
Example
Consider a view with the following segments:
1 - TXW_FI_HD FI document header
2 - TXW_FI_POS FI document item
3 - TXW_GLACC G/L account master
Case a): All documents should be selected. The above order is optimal.
Case b): Only documents which refer to one or few G/L accounts should be read. With the above order, DART would still read all FI document headers and items, but would reject those that don't refer to any of the specified accounts. To avoid reading too many documents, it is better to reverse the order:
1 - TXW_GLACC G/L account master
2 - TXW_FI_POS FI document item
3 - TXW_FI_HD FI document header
Now, only those document lines and corresponding headers will be read, that include the specified accounts.
Case c): Consider this order:
1 - TXW_GLACC G/L account master
2 - TXW_FI_HD FI document header
3 - TXW_FI_POS FI document item
This order is not recommended because there is no direct link between FI document header and account (account is only in document item). This order implies that all document headers are repeatedly scanned for each account. This will result in a very long runtime.
A given order of segments will only give good performance, if the dependent segments can be accessed via an index. In the above case a) this requires an index by document number for FI document items and an index by account for the account master segment. Case b) requires an index by account for the document item segment.
History
Last changed by/on | SAP | 19980728 |
SAP Release Created in |