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ADD_KEY

DELETE_KEY

INDEXED

OPTIMIZE

RELATIVE

SEQUENTIAL

TOUCHUP

Line plot

Surface plot

EDIT/FDL INVOKE — VMS 5.4

 The Invoke function starts a pre-defined interactive session called a
 script.  The FDL Editor uses scripts to ensure that complex
 operations, (like designing a new FDL file) are completed in a logical
 fashion.

 If a script is aborted with a control/Z, the operations and
 calculations performed within that script are discarded (except for
 the clearing of the previous definition, which can't be undone).
 These scripts assume that the files being designed reside on a
 Files-11 disk.

Additional information available:

ADD_KEYDELETE_KEYINDEXEDOPTIMIZERELATIVESEQUENTIAL
TOUCHUP

ADD_KEY

 Modeling and addition of a new index's parameters.  See documentation
 under the "INDEXED" script for more information about the design modes
 used in this script.

DELETE_KEY

 Removal of the highest index's parameters

INDEXED

 The FDL Editor asks several questions and then enters a graphical
 design mode that allows modeling of the indices of the file.

 Two such modes are available:  Line_plot and Surface_plot modes.
 These refer to the type of graph on which EDIT/FDL will display its
 calculated design choices.  The basic goal of these plots is to allow
 you to choose the best trade-off between index bucket size versus
 index depth.  While many of the other file parameters have a
 significant effect on file performance, these two are the most
 important.

Additional information available:

Line plotSurface plot

Line plot

 This design mode uses a graph that responds to adjustments in the file
 design parameters.  The current values of the parameters are shown at
 the bottom of the screen and you set them to new values to see their
 effect on the depth of the index.

Surface plot

 This design mode will graph a surface that indicates index depth
 versus bucket size versus one other parameter, which is swept through
 a range of values.  The choice of the 'other parameter' which is swept
 through a range is:  Load Fill Percent, Key Length, Record Size,
 Initial Load Record Count, and Additional Record Count.

 To aid in selecting an optimal bucket size for a particular value of
 'other parameter', a Recommended Range is delimited on the surface
 plot.  Bucket size values within this range should provide a
 reasonably good trade-off between a flatter index (less I/O) and
 larger buckets (more RMS processing).  Depending on your terminal's
 capabilities, the Recommended Range is delimited either with "/"s on
 either side or by the lightest or green shading.  The left-most edge
 of the Recommended Range will produce the flattest file for a given
 bucket size, but if you're not very sure of the real-life accuracy of
 all the answers given about the application environment, it is better
 to be more conservative and choose a value somewhere closer to the
 middle of the Recommended Range.  The default answer to the bucket
 size question is equivalent to the left-most edge of the Recommended
 Range.

OPTIMIZE

 This script is basically a Redesign of a particular index, with the
 additional feature of using actual file structure data.  The
 ANALYZE/RMS_FILE utility can gather the required statistics with the
 DCL ANALYZE/RMS/FDL command (which produces an FDL file containing
 Analysis_of_area and Analysis_of_key Primary sections).

 The /ANALYSIS=file-spec qualifier of the DCL EDIT/FDL command is used
 to input that information into the FDL Editor.

RELATIVE

 Selection of parameters for a Relative file

SEQUENTIAL

 Selection of parameters for a Sequential file

TOUCHUP

 This script allows the modification of one index's parameters at a
 time.  Only those FDL attributes pertaining to the chosen index are
 changed.  See documentation under the "INDEXED" script for more
 information about the design modes used in this script.

Typewritten Software • bear@typewritten.org • Edmonds, WA 98026