SSL Introduction
U929-J-Z125-9-76 133
Dokuschablonen 19x24 Version 7.3us für FrameMaker V7.x vom 14.02.2007 © cognitas GmbH 2001-2007 24. Oktober 2007 Stand 08:58.55 Pfad: G:\vogt\fsc\ud s\Manuale\en\udsent_e\uds ent.k05
The following applies to the value range for a record sequence number (RSQ):
–1 ≤RSQ ≤ 2
24-1 for databases with a 2048-byte page length if the record type is not
an owner in any set.
–1 ≤ RSQ ≤ 224- 216- 1 for databases with a 2048-byte if the record type is an owner in
a set.
–1 ≤ RSQ ≤ 2
31-1 for databases with a 4000/8096-byte page length
Structure of the DBTT
In order to locate the physical placement of a record via the da tabase key value, UDS/SQL
uses the database key translation table or DBTT.
UDS/SQL automatically sets up a DBTT for every record type. The DBTT contains exactly
one line for every record of a record type. A DBTT line is divided into columns. Co lumn 0
contains the page address of the record. The DBTT of a reco rd type which is not an owner
consists of column 0 only.
The database key value is contained only implicitly in the DBTT. It is symbolized by the
place where the associated physical page address is entered. For example, the record with
RSQ=3 is stored in line 3 of the DBTT; the record with RSQ=9 is stored in line 9, etc.