The RDB$INDICES system table contains information about indexes
in the database. The following table provides information on the
columns of the RDB$INDICES system table.
Data
Column Name Type Summary Description
RDB$INDEX_NAME char(31) A unique index name.
RDB$RELATION_NAME char(31) The name of the table in
which the index is used.
RDB$UNIQUE_FLAG integer A value that indicates
whether duplicate values
are allowed in indexes, as
follows:
o 0
If duplicate values are
allowed.
o 1
If no duplicate values
are allowed.
RDB$ROOT_DBK char(8) A pointer to the base of
the index.
RDB$INDEX_ID integer The identifier of the
index.
RDB$FLAGS integer Flags.
RDB$SEGMENT_COUNT integer The number of segments in
the key.
RDB$DESCRIPTION list A user-supplied description
of byte of this index.
varying
RDB$EXTENSION_PARAMETERS list Stores NODE SIZE value,
of byte PERCENT FILL value,
varying compression algorithm, and
compression run length for
this index. Also reserved
for other future use.
RDB$CARDINALITY bigint The number of unique
entries for a non-unique
index. For a unique index,
the number is 0.
RDB$SECURITY_CLASS char(20) Reserved for future use.
RDB$CREATED date vms Set when the index is
created.
RDB$LAST_ALTERED date vms Set when SQL ALTER INDEX
statement is used.
RDB$INDEX_CREATOR char(31) Creator of this index.
RDB$KEY_CLUSTER_FACTOR bigint(7) Sorted Index: The ratio
of the number of clump
changes that occur when
you traverse level-
1 index nodes and the
duplicate node chains
to the number of keys in
the index. This statistic
is based on entire index
traversal. This means last
duplicate node of current
key is compared with first
duplicate node of next key
for clump change.
Hash Index: The average
number of clump changes
that occur when you go
from system record to hash
bucket to overflow hash
bucket (if fragmented), and
traverse the duplicate node
chain for each key. This
statistic is based on per
key traversal.
RDB$DATA_CLUSTER_FACTOR bigint(7) Sorted Index: The ratio of
the number of clump changes
that occur between adjacent
dbkeys in duplicate chains
of all keys to the number
of keys in the index. For
unique index, the dbkeys of
adjacent keys are compared
for clump change. This
statistic is based on
entire index traversal.
This means last dbkey of
current key is compared
with first dbkey of next
key for clump change.
Hashed Index: The average
number of clump changes
that occur between adjacent
dbkeys in a duplicate chain
for each key. For a unique
index, this value will be
always 1. This statistic is
based on per key traversal.
RDB$INDEX_DEPTH integer Sorted Index: The depth of
the B-tree.
Hashed Index: This column
is not used for hashed
indices and is left as 0.
1 – RDB$FLAGS
Represents flags for RDB$INDICES system table.
Bit
Position Description
0 Hashed index.
1 Index segments are numeric with mapping values
compression.
2 Hashed ordered index. (If bit is clear, hashed
scattered.)
3 Reserved for future use.
4 Run-length compression.
5 Index is disabled or enabled deferred.
6 Build pending (enabled deferred).
7 Reserved for future use.
8 Reserved for future use.
9 Reserved for future use.
10 Reserved for future use.
11 If on, duplicates are compressed.
12 Sorted ranked index.
13 Prefix cardinalities disabled.
14 Use the full collection algorithm for prefix
cardinality.
15 Index generated for a constraint when SET FLAGS 'AUTO_
INDEX' was enabled.