User Guide

SAP AG November 2002
Table Access (INSERT) Using B* Tree
SAP DB Data Page
Ardwick|.......
ensen|..... Arnhem |...
1
45
362
INSERT INTO address SET city = 'Arbon'
INSERT INTO address SET city = 'Arbon'
Apach |. Ap-
Arbon |.......
Ardwick|........
Anizy |.......
Apach |.
Apensen|.....
Arnhem |...
Athens |Greece
7
Arbon |
.....
Anizy |.......
Athens |Greece
Arbon |.......
The address table is defined via the city
column. In the address table,
insert an entry with the value Arbon for the city primary key field.
primary key [Page
101]
If there is enough space in the
of the for the new
entry, SAP DB inserts the entry at the end of the data section and updates the position list.
The address of the new entry is written to the correct position in the position list. In the
example above, this is position 4. Position 4 points to the new table entry number 7.
leaf page [Page
103] B* tree [Page 128]
The position list and data section converge when data is inserted in a data page.
Table Access (DELETE) Using B* Tree
Table Access Using B* Tree [Page 107] is illustrated using the example of a DELETE
statement.
User Manual: SAP DB 110