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Gold Medal Software 3
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Gold Medal Software - Volume 3 (Gold Medal) (1994).iso
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ddf606a.arj
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HELPDOC.EXE
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FILTER.HLP
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╒═══════════════════════════════════════════════════════════════════╕
│ Creating a Filter │
╘═══════════════════════════════════════════════════════════════════╛
The purpose of a Filter is to "hide" all records not meeting the
requirements that you specify for a given field. This will allow you
to edit, view or print only the sub-set of records in the filter.
The Filter sub-menu can be accessed from either the "Filter
Create/Select" command in the main menu or while editing records by
pressing <Alt-F>. Either way, if a filter has not been created the
menu will have the following two choices:
A) Marked Records
B) Field Data
If a filter has already been created the sub-menu will have the
following three choices:
A) Create New Filter
B) Set Filter ON/OFF
C) Continue Filter
IF A FILTER HAS NOT BEEN CREATED:
─────────────────────────────────
A description of Marked Records and Field Data is explained below
under Create New Filter but first there are a few possible messages
you may receive.
The first one is "Filter field has not been assigned". If this
happens you will be allowed to assign a logical field (type "L") to
be used for filtering. Normally you would have to select General
Setup in the main menu then Field Assignment, however this is all
done automatically for you here. If in the box of fields there is no
type "L" field that you want to assign exclusivly for filtering then
you will need to modify the database to include one. In the sample
database provided with the program we include one named "filt". The
field can have any name you choose.
To Modify a Database, first close the database. Then modify it with
"Create/Modify Database Files" in the main menu. See "Creating or
Modifying a Database" in the help menu. After modifying the file,
reselect it and assign the newly added logical field to the Filter
field.
Note that the above logical field is going to be used by DDFile and
not yourself. You will not be setting a Filter to the assigned
logical field. Also, if you do not have a logical field that can be
used exclusively by "Duplicate Records Search" in the main menu, you
will also want to add a field for it while you are modifying the
database.
The message; "Index set to natural record order for filter." will
appear if an index is set. This is done to speed up the Filtering
process. You will need to reselect the Controlling Index after
setting the filter.
The question; "Use previously set filter? (Y/N)" will appear if a
Filter was set while last using the database. Otherwise the following
sub-menu will appear allowing these choices:
IF A FILTER HAS ALREADY BEEN CREATED:
─────────────────────────────────────
A) Create New Filter
─────────────────────────────────────────────────────────────────────
This selection will allow you to create a new Filter to Marked
records or Field Data. The following two commands will also appear in
a menu by themselves if a filter has not already been created.
A) Marked Records ───────────────────────────────────────────────
This selection will set a Filter to Marked records. If Marked
records are turned off, they will be turned back on.
B) Field Data ───────────────────────────────────────────────────
This selection will allow you to specify requirements on selected
fields for which a Filter will be set. There are three steps for
each requirement you want to specify in the Filter. In the first
step a field will need to be selected.
Next, select a method of search. There are nine methods of search
available for character, memo and numeric fields, six for date
fields and three for logical fields.
The following are the available operators.
"1) Search from BEGINNING of field only on CURRENTLY selected
records." This method of search will set a Filter to the records
that equal the requirement you are about to specify for the
field. Each time this method of search is selected, the
requirement is searched for within the records meeting the last
requirement specified. This will narrow down the number of
records in the Filter.
"2) Search from BEGINNING of field looking at ALL records in
database." This method of search will allow two or more EQUAL
requirements to be specified for any one field. Each time this
method of search is selected, the requirement is searched for
throughout the entire database and any records meeting the
specified requirement are then added to the Filter.
"3) Search from BEGINNING of field EXCLUDING those meeting
specification." This method of search will exclude all records
from the Filter or database that do not meet the specified
requirement.
"4) Search for RANGE in field only on CURRENTLY selected
records." This method of search will set a Filter to the records
that meet the specified MINIMUM and MAXIMUM range.
"5) Search for RANGE in field looking at All records in
database." This method of search will allow two or more RANGE
requirements to be specified for any one field. Each time this is
done, all records in the database meeting the range requirements
will be included in the Filter.
"6) Search for RANGE in field EXCLUDING those meeting
specification." This method of search will exclude all records
from the Filter or database that do not meet the specified
requirement.
"7) Search from WITHIN field only on CURRENTLY selected records."
This method of search will set a filter to all records that
contain the requirement anywhere WITHIN the selected field. For
example, you could set a Filter to all records that have a Street
Address name of Elm which would be WITHIN the Street Address
field.
"8) Search from WITHIN field looking at All records in database."
This method of search will allow two or more WITHIN requirements
to be specified for any one field. Each time this method of
search is chosen, the entire database is searched for the
specified requirement WITHIN the selected field. All records
meeting the requirement will be included in the filter.
"9) Search from WITHIN field EXCLUDING those meeting
specification." This method of search will exclude all records
from the Filter or database that do not meet the specified
requirement.
"Ignore case structure?" After selecting a method of search, you will
be asked if you want to ignore the case structure. If Yes, upper and
lower case letters will be recognized as the same.
If there are no records in the database that meet the specifications
entered, no Filter will be set and a message will appear saying there
are no records available matching the requirements specified.
"Tally Records in filter?" After each requirement is specified you
will be asked if you want to tally the records in the filter up to
that point. The tally is optional because of the time it takes to
count. A non-optional tally is made once the Filter is completed.
"Select another field?" Next, you will be asked if you want to select
another field. If so, this three-step process will be repeated.
In using the first three methods of search, note that the field
content specified does not have to match, in length, the actual
content of the field. For example, if "We" were specified in the
"Last Name" field, the search would include all records with a Last
name field content that start with "We" which would include "Webber",
"Webster", "Wealler", and so on.
Blank fields may be checked by selecting the first method of search
and pressing <Enter>, not specifying a requirement for the field.
The following example uses a "state" field. If your database does not
contain a "state" field, the same principle can be applied to another
field. To set a Filter to all records in the states of Arizona (AZ),
California (CA), Nevada (NV), and Utah (UT): First, select the
"State" field. Next, select the second method of search. Then specify
"AZ" for the field content. Do the same for the other three states.
Each time the Filter will increase in size assuming you have records
from those states.
To continue the above example Filter, include only the records from
those states who have a last name in the RANGE of "A" to "L". First,
select the "Last name" field. Next, select the fourth method of
search. Do not select the fifth since we do not want to search the
entire database. Enter "A" for the START OF RANGE then "L" for the
END OF RANGE.
At this time if the steps above were followed correctly your Filter
includes all records that have a Last name field initial in the range
of "A" to "L" and are from the states AZ, CA, NV, and UT.
B) Set Filter ON/OFF
─────────────────────────────────────────────────────────────────────
This selection will toggle the Filter ON or OFF. When the filter is
turned ON, ONLY the records within the Filter may be edited, viewed,
and printed. In order to edit, view, or print all records in the
database the Filter must be turned OFF.
C) Continue Filter / Not Available
─────────────────────────────────────────────────────────────────────
This selection will be "Continue Filter" if the current filter was
set on Field Data, otherwise the prompt will be "Not Available".
If the current Filter was created on Field Data, you may continue the
filter by specifying more requirements on field content without
creating a new Filter. Selecting this command will display the same
screen as when creating a new Filter.