USE FILEDEF TO PUT IT ALL TOGETHER - DataFlex V2 Jul1984 pdf

This section takes a procedural step-by-step look at how DataFlex's FILEDEF

_utility

can be used _{to create} and _{maintain the} data

_files

_of an application.

To execute _{the program type} "FILEDEF" _{at the operating} system "A>" prompt _{or select}

it

from the CONFIGURATION NENU. The program will

sign on and present a serles of prompts in order to obtain the data needed _{to define the} data

_file,

Each _{of the} prompts from FILEDEF _is

presented here _{with the} how _to's on their use and _their _relationship

to the rest of the DataFlex system. IF YOU MAKE AN INCORRECT ENTRY:

Some FILEDEF menu choices proceed _through a series of prompts, which must be answered _{in order to continue.}

_If

_at any pofntp you are not

sure of the answer9 _or you key a wrong response9

_it

_still

necessary

to answer all of the questions, at 1east'w1th something that satisfies

the program, in order to proceed and get back to the FILEDEF

operations menu. Once _all _{the questions} have been answerech however,

the menu (see below) _gives _you _{the opportunity} _{to modify your earlier} answers _{or to} abandon them _altogether _(choice 10)» and _{leave your}

original

_{file (if}

any) unchanged.

—

="=~=__"=="=="""—

———~———

DataFlex 2.0 User's Manual FILE DEFINITION (FILEDEF) C-57 =

ENTER FILE NUMBER:

When _{run, the} FILEDEF Program prompts _{the configurator} _with a

_list

of currently defined

_files.

You may modify one of theseg _enter an unused

file

number _{to start} a new

_file

_{or reactivate} one not currently on the

1 i_st.

As a shortcutg you may _enter FILEDEF <FILENUMBER> _{at the operating} system command _level _to pass a

_file

number _directly _{to the} program

without going through the

_files

menu. NEW FILE (YIN)

If

you have _selected a

_file

number _that does _not appear in the

_file

list

then you must

_tell

FILEDEF

if

this is a new

_file

_or an inactive

one .

If

you are creating this

_file

for the

_first

time answer the question

with a "Y".

If

file

definition for this fi1e already exists, answer the question with the "N" response (you can just press enter to default to the "N"

responseL which _will _give you the chance _{to reactivate} _the

_file.

The system _will _then ask _{for the} ROOT name, USER DISPLAY nameg and _Data-

Flex filename of the

_file.

DataFlex appl _ication _{configurations} purchased _separately which

are installed on an existing DataFlex system must have _their

_file

numbers

re-activated as described above.

If

you are modifying or re-activating an existing

_file

definitiong the

FILEDEF menu will be displayed. Otherwise, for a new

_file,

some

preliminary information will be _required: ROOTNAME

The ROOTNAME _refers _{to the} base name of any DataFlex data or configuration

_file

created by FILEDEF. The ROOTNAME must conform _to

operating system _{filename conventions of} up to eight letters and numbers. _{DataFlex will} append _{the appropriate} _extension based _on _the use of a particular physical

_file

(see _{the appendix).} Make up an 8

character or smaller rootname _{for your}

_file

WITHOUT AN EXTENSION!

If

you wish _{to specify the drive} on which DataFlex is to place the data _filem _prefix _the

_file

name with the _{drive specification} _{in the}

standard format: drive letter (A..P) followed by _":

"

followed by

filename.

EXAMPLE ROOTNAME W/DRIVE SPEC.: B: MYFILE

This would be a

file

called "MYFILE" located on disk drive "B".

C-58 FILE DEFINITION (FILEDEF) _{DataFlex 2.0 User's} Manual ——— USER DISPLAY _Nm:

The User _display name is the one which _will be _{displayed in the} FILE SELECTION menus by DataF1ex programs. Enter the name you would _like _to see displayed to the operator for this

file.

If

the

file

name is preceded _with a "@"

it

will not display on the runtime

_file

display

menus. The maximum length of the user display name is 30 _characters.

DataFlex FILENAME

The DataF1ex _filename can be up to ten characters long and must _start

with a letter. The DataFlex filename is used to reference a data

_file

from _{configurations.} _{In that}

it

does _{not contain drive specifications}

it

is a "soft" reference to a

_file

that makes an application indepen-

dent of a particular hardware configuration.

It

is also usedg along

with a field's Tagname, to define DATA BASE ELEMENT names within a

file.

RECORD LENGTH

This is the physical size (in bytes) of the record you

_will

creating. DataFlex _will _{automatically} _block sma?1 _{records into} 512

byte blocks. Larger records can be any multiple of 128 _bytes. You can assign _{the record length} by _selecting _option 4 from _the FILEDEF

operations menu.

If

there is a conflict between what _you _assign as

the record length and what _{the syst«n} needs _{to correctly} _{block the} recorcb the necessary record length will be blocked _autwat1ca11y by FILEDEF when you enter the record length.

If

you know the record length at this point, you may _enter

_it.

_If

you are creating a definition from an IMAGE and _don't know _{the record}

size, you may

_initialize

_it

_{to zero.} The READ SCREEN _option

_will

then

set the record length for you. DataF1ex _will _{block records in all}

sizes from

_l

_to 26 _bytes, 28 _bytes, 3Ó9 32p 35» 39, 42p 46p _{5L 5&} 649 73,t 85» l029 128, l7Ch 256, and upward _{in multiples} _of 128 _bytes,

to a maximum to 4 _kilobytes.

MAX # OF RECORDS

The _{value entered} here _{is the} maximum number _{of records to} be _stored

in the database _{for this}

_file.

The _figure _{entered here is} non-

critical

unless you elected the system _option (see _Installing

DataFlex) which _{provides for pre-a11ocation} _{of disk} space for the

maxium _{possible size of your database.} Otherwisep you may feel free

to make some growing room available for the number _{of records in} a

particular

_file.

The _absolute maximum number _{of records in} a DataFlex

_file

is 64AOO. NOTE:

_If

_the need _{arises to} expand _the maximum number _{of records after} a

_file

contains datag _re-enter FILEDEF and _enter a larger value for this

_field.

Then, run the REINDEX

utility

to rebuild the index(s) under _the new parameter.

DataFlex 2.0 _User's Manual FILE DEFINITION (FILEDEF) C-59 ——————

———————— -—————- REUSE DELETED SPACE (YIN)

For most _applications you

will

want _{DataFlex to reassign the disk} space released when a record is deleted from a

_file,

howevem _in

applications where you want _to use the record number as an audit

_trail

or as a transaction number, _this would _not be _desirable. To _{allow the}

re-use of deleted spacep enter <Y>es; _{otherwiseg enter} <N>o. mLTI-UsER RE-READ _(YIN):

If

you are running on a multi-user systan (and you have a multi-user version of DataFlex) and you wish _{for this}

_file

_to

_utilize

_{the feature}

of allowing multiple users to write to the same record at the same

time then _enter a 'Y', otherwise, enter 'N'. NOTE: MULTIUSER _option

of SETSCREEN must be _{set to} (Y) _to

_utilize

RE-READ. THE FILE DEFINITION MENU

After completing the entries just covered about R00TNAMEp _etc., _the FILEDEF _operations menu

_will

be displayed.

It

looks like this:

l:

CREATE/EDIT FIELD SPECIFICATIONS 2: CREATE/EDIT INDEXES

3: DISPLAY/PRINT FILE DEFINITION 4: SET FILE PARAMETERS AND NAMES 5: ERASE DATA FILE

6: SET FILE INACTIVE

7: CREATE FILE DEFINITION FROM SCREEN IMAGE 8: CREATE FILE DEFINITION FROM .DEF IMAGE 9: SAVE DEFINITION AND EXIT FILEDEF

IQ: ABORT FILEDEF, DO NOT UPDATE DEFINITION FILE You may enter one of the option numbers

_(l

- 10) to select your next action. For new

files

you MUST either execute _Options

_l

and 2, _or Option _7. The _results _{of using Option I or} Option 7 are the same:

creation of a DataFlex

_file

_definition. The methods used _to reach

that end are different: option one takes you field by _field _through

the record definition where you make _{the specification} _entries

manually. Option 7 _functions _just _like _{the DataFlex} AUTODEF

_Utility

and determines _{the record structure} autanatical1y from _the screen image.

C-60 FILE DEFINITION (FILEDEF) _DataFlex 2.0 _User's Manual OPTION _I

In document DataFlex V2 Jul1984 pdf (Page 168-172)