A directory in which to store the index files. The
default is the empty string, which means use the database directory.
This can be used to put the indexes onto another disk to balance load
or for space reasons. If indexspace is set to a non-default
value when a Metamorph index is being updated, the new index will be
stored in the new location.
indexblock
When a Metamorph index is created on an indirect field,
the indirect files are read in blocks. This property allows the size
of the block used to be redefined.
indexmem
When indexes are created Texis will use memory to speed up the
process. This setting allows the amount of memory used to be
adjusted. The default is to use 40% of physical memory, if it
can be determined, and to use 16MB if not. If the value set is less
than 100 then it is treated as a percentage of physical memory. It
the number is greater than 100 then it is treated as the number of
bytes of memory to use. Setting this value too high can cause
excessive swapping, while setting it too low causes unneeded extra
merges to disk.
indexmeter
Whether to print a progress meter during index creation/update.
The default is 0 or 'none', which suppresses the meter.
A value of 1 or 'simple' prints a simple hash-mark meter
(with no tty control codes; suitable for redirection to a file and
reading by other processes). A value of 2 or 'percent' or
'pct' prints a hash-mark meter with a more detailed percentage
value (suitable for large indexes). Added in
version 4.00.998688241 Aug 24 2001.
addexp
An additional REX expression to match words to be indexed. This is
useful if there are non-English words to be searched for, such as part
numbers. When an index is first created, the expressions used are
stored with it so they will be updated properly. The default
expression is \alnum{2,99}. Note: Only the expressions
set when the index is first created are saved. Expressions set
during an update (issuance of ``create metamorph [inverted]
index'' on an existent index) will not be added.
delexp
This removes an index expression. Expressions can
be removed either by number or by expression.
lstexp
Lists the current index expressions. The
value specified is ignored (but required).
addindextmp
Add a directory to the list of directories to use
for temporary files while creating the index. If temporary files are
needed while creating a Metamorph index they will be created in one of
these directories, the one with the most space at the time of
creation. If no addindextmp dirs are specified, the default
list is the index's destination dir (eg. database or indexspace),
and the environment variables TMP and TMPDIR.
delindextmp
Remove a directory from the list of directories to
use for temporary files while creating a Metamorph index.
lstindextmp
List the directories used for temporary files while
creating Metamorph indices. Aka listindextmp.
btreethreshold
This sets a limit as to how much of an index should
be used. If a particular portion of the query matches more than the given
percent of the rows the index will not be used. It is often more efficient
to try and find another index rather than use an index for a very frequent
term. The default is set to 50, so if more than half the records match,
the index will not be used. This only applies to ordinary indices. See
infthresh and infpercent for control of Metamorph indices.
maxlinearrows
This set the maximum number of records that should
be searched linearly. If using the indices to date yield a result set
larger than maxlinearrows then the program will try to find more
indices to use. Once the result set is smaller than maxlinearrows,
or all possible indices are exhausted, the records will be processed. The
default is 1000.
likerrows
How many rows a single term can appear in, and still be
returned by liker. When searching for multiple terms with liker
and likep one does not always want documents only containing a
very frequent term to be displayed. This sets the limit of what is
considered frequent. The default is 1000.
indexaccess
If this option is turned on then data from an index
can be selected as if it were a table. When selecting from an
ordinary index, the fields that the index was created on will be
listed. When selecting from a Metamorph index a list of words and
number of documents containing each word will be returned.
indexchunk
In versions of Texis after October 1998, the
indexchunk setting is deprecated and unused. In prior releases,
when creating a Metamorph index temporary files are
used which in the worst case can grow to twice the size of the data
being indexed. This process can be broken into stages, such that
after indexing a certain amount of data the temporary files are
processed, to generate a partial index, and then the process repeats
for the rest of the data. By default the amount of free disk space is
checked on startup, and used to calculate when it will need to perform
the processing step. If the system does not report free disk space
accurately, or to free more disk space, this value can be changed.
The default is 0, which automatically calculates a value. Otherwise
it is set to the number of bytes of data to index before processing
the temporary files. Lower values conserve disk space, at the expense
of more time to process intermediate files.
cleanupwait
Windows/NT specific After updating a
Metamorph index the database will wait this long before trying to
remove the old copy of the index. This is to allow any other process
currently using the index time to stop using the index, so it can be
removed. The default is twenty seconds. If a whole batch of
Metamorph indices are being updated right after another, it may be
useful to set this to 0 for all but the last index, as an attempt will
be made to remove all old indices after every index update.
indextrace
For debugging: trace index usage, especially during
searches, issuing informational putmsgs. Greater values
produce more messages. Note that the meaning of values, as well as
the messages printed, are subject to change without notice.
Aka traceindex, traceidx. Added
in version 3.00.942186316 19991109.
tracerecid
For debugging: trace index usage for this particular
recid. Added in version 3.01.945660772 19991219.
indexdump
For debugging: dump index recids during search/usage.
Value is a bitwise OR of the following flags:
Bit 0
for new list
Bit 1
for delete list
Bit 2
for token file
Bit 3
for overall counts too
The default is 0.
indexmmap
Whether to use memory-mapping to access Metamorph
index files, instead of read(). The value is a bitwise OR
of the following flags:
Bit 0
for token file
Bit 1
for .dat file
The default is 1 (ie. for token file only). Note that memory-mapping
may not be supported on all platforms.
indexreadbufsz
Read buffer size, when reading (not
memory-mapping) Metamorh index .tok and .dat files. The
default is 64KB; suffixes like ``KB'' are respected. During
search, actual read block size could be less (if predicted) or more
(if blocks merged). Also used during index create/update. Decreasing
this size when creating large indexes can save memory (due to the
large number of intermediate files), at the potential expense of time.
Aka indexreadbufsize. Added in version 4.00.1006398833
20011121.
indexwritebufsz
Write buffer size for creating Metamorph
indexes. The default is 128KB; suffixes like ``KB'' are
respected. Aka indexwritebufsize. Added in version
4.00.1007509154 20011204.
indexmmapbufsz
Memory-map buffer size for Metamorph indexes.
During search, it is used for the .dat file, if it is
memory-mapped (see indexmmap); it is ignored for the
.tok file since the latter is heavily used and thus fully
mapped (if indexmmap permits it). During index update,
indexmmapbufsz is used for the .dat file, if it is
memory-mapped; the .tok file will be entirely memory-mapped if
it is smaller than this size, else it is read. Aka
indexmmapbufsize. The default is 0, which uses 25% of RAM.
Added in version 3.01.959984092 20000602. In version 4.00.1007509154
20011204 and later, ``KB'' etc. suffixes are allowed.
indexslurp
Whether to enable index ``slurp'' optimization
during Metamorph index create/update, where possible. Optimization is
always possible for index create; during index update, it is possible
if the new insert/update recids all occur after the original recids
(eg. the table is insert-only, or all updates created a new block).
Optimization saves about 20% of index create/update time by merging
piles an entire word at a time, instead of word/token at a time. The
default is 1 (enabled); set to 0 to disable. Added in version
4.00.1004391616 20011029.
indexappend
Whether to enable index ``append'' optimization
during Metamorph index update, where possible. Optimization is
possible if the new insert recids all occur after the original recids,
and there were no deletes/updates (eg. the table is insert-only); it
is irrelevant during index create. Optimization saves index build
time by avoiding original token translation if not needed. The
default is 1 (enabled); set to 0 to disable. Added in version
4.00.1006312820 20011120.
indexwritesplit
Whether to enable index ``write-split''
optimization during Metamorph index create/update. Optimization saves
memory by splitting the writes for (potentially large) .dat
blocks into multiple calls, thus needing less buffer space. The
default is 1 (enabled); set to 0 to disable. Added in version
4.00.1015532186 20020307.
[indexbtreeexclusive] Whether to optimize access to certain
index B-trees during exclusive access. The optimization may reduce
seeks and reads, which may lead to increased index creation speed on
platforms with slow large-file lseek behavior. The default is
1 (enabled); set to 0 to disable. Added in version 5.01.1177548533
20070425.
mergeflush
Whether to enable index ``merge-flush'' optimization
during Metamorph index create/update. Optimization saves time by
flushing in-memory index piles to disk just before final merge;
generally saves time where indexslurp is not possible. The
default is 1 (enabled); set to 0 to disable. Added in version
4.00.1011143988 20020115.
indexversion
Which version of Metamorph index to produce or
update, when creating or updating Metamorph indexes. The supported
values are 0 through 3; the default is 2. Setting version 0 sets the
default index version for that Texis release. Note that old versions
of Texis may not support version 3 indexes. Version 3 indexes may use
less disk space than version 2, but are considered experimental.
Added in version 3.00.954374722 20000329.
indexmaxsingle
For Metamorph indexes; the maximum number of
locations that a single-recid dictionary word may have and still be
stored solely in the .btr B-tree file (without needing a
.dat entry). Single-recid-occurence words usually have their
data stored solely in the B-tree to save a .dat access at
search time. However, if the word occurs many times in that single
recid, the data (for a Metamorph inverted index) may be large enough
to bloat the B-tree and thus negate the savings, so if the
single-recid word occurs more than indexmaxsingle times, it is
stored in the .dat. The default is 8.
uniqnewlist
Whether/how to unique the new list during
Metamorph index searches. Works around a potential bug in old
versions of Texis; not generally set. The possible values are:
0
: do not unique at all
1
: unique auxillary/compound index new list only
2
: unique all new lists
3
: unique all new lists and report first few duplicates
The default is 0.
tablereadbufsz
Size of read buffer for tables, used when it is
possible to buffer table reads (eg. during some index creations). The
default is 16KB. When setting, suffixes such as ``KB'' etc.
are supported. Set to 0 to disable read buffering. Added in version
5.01.1177700467 20070427. Aka tablereadbufsize.