Fujitsu UDS/SQL V2.5 用户手册
Linkage methods
SSL
148
U929-J-Z125-9-76
Storing a set occurrence as a list
MODE IS LIST
If a set is defined with MODE IS LIST, UDS/SQL stores the member records of a set occur-
rence in a table called a list. The physical sequence of the records corresponds to the
logical sequence defined in the ORDER clause.
rence in a table called a list. The physical sequence of the records corresponds to the
logical sequence defined in the ORDER clause.
Figure 35: Set occurrence stored as a list
If a list occupies more than one page, each page is linked twice by act-keys.
If ORDER IS SORTED INDEXED, the list is provided with additional higher-ranking table
levels. The higher-ranking levels have the same structure as that of a pointer array.
levels. The higher-ranking levels have the same structure as that of a pointer array.
. .
. . . . . . .
. .
. . . . . . .
Moore
. . .
Owner record
DBTT
List
Beer
Cocoa
Milk
Gin
. . .
. . .
. . .