Guardian Procedure Calls Reference Manual (G06.25+)

Guardian Procedure Calls (F)
Guardian Procedure Calls Reference Manual—522629-013
5-9
FILE_ALTERLIST_ Procedure
key-len
(INT:1)
specifies the length, in bytes, of the
alternate-key field. The maximum key
length of an alternate key that allows
duplicates and is defined as insertion-
ordered (see
attributes, below) is:
255 - (10 + primary key length)
For unique keys, the maximum is 253.
For normal duplicates, the maximum is
(253 - primary-key length).
Refer to the
Enscribe Programmer’s
Guide for further information.
key-offset
(INT:1)
is the number of bytes from the beginning
of the record to where the alternate-key
field starts.
key-filenum
(INT:1)
is the relative number in the alternate-key
parameter array of this key’s alternate-key
file. The first alternate-key file’s
key-
filenum
is 0.
null-value
(INT:1)
Specifies a null value if
attributes.<0> =
1. Note that the character must reside in
the righthand byte.
During a write operation, if a null value is
specified for an alternate-key field, and the
null value is encountered in all bytes of
this key field, the file system does not
enter the reference to the record in the
alternate-key file. (If the file is read using
this alternate-key field, records containing
a null value in this field will not be found.)
During a writeupdate operation (
write-
count
= 0), if a null value is specified, and
the null value is encountered in all bytes of
this key field within
buffer, the file system
deletes the record from the primary file but
does not delete the reference to the
record in the alternate file.
attributes
(INT:1)
Contains the following fields:
Table 5-2. FILE_ALTERLIST_ Item Codes (page5of9)
Items in this table with a size of 2 bytes are of data type INT. The term “disk file”
applies only to Enscribe files. The term “disk object” applies to Enscribe files and
SQL objects.
Code
Size
(bytes) Description