Fujitsu J2X0-2273-01EN User Manual

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[Figure: Overview of SEQUENTIAL structure]
 
 
 
 
SEQUENTIAL structure features for data processing patterns
 
The factor having the greatest effect on data processing efficiency is the I-O frequency. The SEQUENTIAL structure 
has the following features: 
 
·  All data is referenced for data processing unless an index exists. Thus, the I-O frequency depends greatly on 
the data volume. When data manipulations specify a column, the user must add an index corresponding to that 
column. 
For information about items to carefully consider when adding an index, see 4.2.1 "BTREE structure." 
SEQUENTIAL structure page size specification
 
In a SEQUENTIAL structure, the page size is specified by the PAGESIZE option of the DSO definition. 
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