ug_ch8.htm

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value, the scanning will begin from the first key.</font></p>
<p>The records located by the scan will be paged and displayed in a
horizontal packed format. This is similar to the format that would
result if the <b>struct</b> variable corresponding to the record
were statically initialized in a C program. That is, it would be
enclosed in braces, { }, with each sub-field grouping separated by
commas. For more information about the display of various
<b><i>db.*</i></b> data types, see section 8.3.3.</p>
</div>
<blockquote style="MARGIN-RIGHT: 0px">
<blockquote style="MARGIN-RIGHT: 0px">
<p>Figure 8-11 shows a sample record scan display.</p>
</blockquote>
</blockquote>
<hr>
<div style="margin-left: 6em">
<pre>
<font color=
"#0000FF">Record: EMPLOYEE      Key: EMP_ID      Page: 1
<br>
ENTRY RECORD CONTENTS
   1.   {"7901",{"Pfeil","Carl","L."},"MGR1"}
   2.   {"7902",{"Rogers","Jim",""}, "MGR1"}
   3.   {"7903",{"Fleagle","Jenifer","C."},"MGR2"}
   4.   {"7904",{"Smith","Stephen","P."},"MGR1"}
   5.   {"7906",{"Warren","Wayne","L."},"MGR1"}
   6.   {"7907",{"Merilatt","Randall","L."},"MGR1"}
   7.   {"8001",{"Bryant","John","W."},"MGR2"}
   8.   {"8002",{"Willis","Kirt","L."},"MGR2"}
   9.   {"8003",{"Mureen","Chris",""}, "ENGR"}
  10.   {"8101",{"Temple","Anita","J."}, "ADMN"}
  11.   {"8102",{"Rodovsky","Eliska",""}, "ENGR"}
  12.   {"8102",{"Marsh","Kyle","G."}, "ENGR"}
  13.   {"8103",{"Carlson","Bob","C."}, "MGR1"}
  14.   {"8104",{"Bustamante","Tina","L."}, "ENGR"}</font>
</pre></div>
<hr>
<p align="center"><font size="2"><b>Fig. 8-11. A Sample
Keyscan/Scan Display</b></font></p>
<p>Keyfind<br>
Quickly finds and displays one record. When you select a key field
from the displayed list and enter a value, this command displays
either the record associated with the specified key value, or if
the key is not found, the record associated with the next key.
Compound key and <b>struct</b> fields must be enclosed by braces ({
}). Character strings do not need to be delimited by quotation
marks except when included as part of a <b>struct</b> field.</p>
<p>First<br>
Finds and displays the record associated with the first key in the
key file.</p>
<p>Last<br>
Finds and displays the record associated with the last key in the
key file.</p>
<p>Next<br>
Finds and displays the record associated with the next key in the
key file. If a <b>Next</b> command causes a "no more keys" message
at the end of a file, a subsequent <b>Next</b> command will return
the first key.</p>
<p>Previous<br>
Finds and displays the record associated with the previous key in
the key file. If a <b>Previous</b> command causes a "no more keys"
message at the end of a file, the next <b>Previous</b> command will
return the last key.</p>
<h4>Get command</h4>
<div style="margin-left: 2em">
<p><font size="2">Displays the record located at a specified
database address. When prompted for the database address, enter it
as:</font></p>
<pre>
<font color=
"#0000FF">enter database address: [<b><i>f</i></b> :<b><i>r</i></b>] </font>
</pre>
<p><font size="2">where <b><i>f</i></b> is the file number and
<b><i>r</i></b> is the record number. Refer to section 14.2.2,
"Data File Organization," for a description of database
addresses.</font></p>
</div>
<h4>Enter command</h4>
<div style="margin-left: 2em">
<p><font size="2">Enters new records into the database. From the
displayed list, select the record type to be entered. The
<b>Display/Edit Record</b> submenu is then invoked. Section 8.4.1,
shows the <b>Display/Edit Record</b> submenu and describes its
functions in detail.</font></p>
</div>
<h4>Modify command</h4>
<div style="margin-left: 2em">
<p><font size="2">Invokes the <b>Display/Edit Record</b> submenu,
which provides a set of tools for modifying the current record,
which may be selected in a variety of ways. For detailed
information, about the <b>Display/Edit Record</b> submenu, see
section 8.3.2.</font></p>
</div>
<h4>Delete command</h4>
<div style="margin-left: 2em">
<p><font size="2">Deletes the current record from the database. The
record must have been previously disconnected from all sets of
which it was an owner or a member.</font></p>
</div>
<h4>Recscan command</h4>
<div style="margin-left: 2em">
<p><font size="2">Invokes the <b>Scan and View Record Based on
Database Address</b> command submenu. The commands in this submenu
use the <b>d_recfrst</b>, <b>d_recnext</b>, <b>d_reclast</b> and
<b>d_recprev</b> functions to locate the records, instead of the
key traversal functions.</font></p>
</div>
<hr>
<div style="margin-left: 4em">
<pre>
<font color=
"#0000FF">Scan and View Record Based on Database Address
Scan  First  Last  Next  Previous  X_exit</font>
</pre></div>
<hr>
<p align="center"><font size="2"><b>Fig. 8-12. Scan and View Record
Based on Database Address Submenu</b></font></p>
<div style="margin-left: 4em">
<p>Scan<br>
Scans records based on their database address (their order is
determined by their physical appearance in a data file). A list of
all record type names will be displayed, from which you should
select the type to be scanned.</p>
<p>The records located by the scan will be paged and displayed in
the same horizontal packed format as the <b>Keyscan</b> command.
For more information about the display of various
<b><i>db.*</i></b> data types, see section 8.3.3.</p>
<p>First<br>
Finds and displays the first record of the selected type in the
data file.</p>
<p>Last<br>
Finds and displays the last record of the selected type in the data
file.</p>
<p>Next<br>
Finds and displays the next record in the data file. When it
reaches the end of the file, it displays a "no more records"
message. A subsequent <b>Next</b> command will begin with the first
record.</p>
<p>Previous<br>
Finds and displays the previous record in the data file. When it
reaches the top of the file, it displays a "no more records"
message. A subsequent <b>Previous</b> command will begin with the
last record.</p>
</div>
<h3>8.4.2 Using the Access Set Commands</h3>
<p><font size="2">Selecting the <b>Set</b> command from the
<b>Database Access Commands</b> submenu, accesses the <b>Set
Manipulation Functions</b> submenu, which provides a set of tools
for managing sets. This submenu is shown in Figure 8-13, followed
by a description of its functions.</font></p>
<hr>
<div style="margin-left: 4em">
<pre>
<b><font color="#0000FF">Set Manipulation Functions</font>
Scan Owner First Next Last Previous Connect Disconnect Total X_exit</b>
</pre></div>
<hr>
<p align="center"><font size="2"><b>Fig. 8-13. Set Manipulation
Functions Submenu</b></font></p>
<h4>Scan command</h4>
<div style="margin-left: 2em">
<p><font size="2">Scans and displays all member records connected
to the current owner of a set. The set to be scanned is selected
from the displayed list of set names.</font></p>
<p>The records located by the scan will be paged and displayed in a
horizontal packed format. This is similar to the format that would
result if the <b>struct</b> variable corresponding to the record
were statically initialized in a C program. That is, it would be
enclosed in braces, { }, with each sub-field grouping separated by
commas. For more information about the display of various
<b><i>db.*</i></b> data types, see section 8.3.3.</p>
</div>
<h4>Owner command</h4>
<div style="margin-left: 2em">
<p><font size="2">Finds the owner of the current record, through
the set selected from the displayed list of set names. Note that
this function serves a different purpose than the Owner function
under the Display/Edit Record submenu.</font></p>
</div>
<h4>First command</h4>
<div style="margin-left: 2em">
<p><font size="2">Finds the first member connected to the current
owner of the set selected from the displayed list of set
names.</font></p>
</div>
<h4>Next command</h4>
<div style="margin-left: 2em">
<p><font size="2">Finds the next member of a set. The first time
(or after a "no more records" message), <b>Next</b> displays the
first member of the set.</font></p>
</div>
<h4>Last command</h4>
<div style="margin-left: 2em">
<p><font size="2">Finds the last member connected to the current
owner of the set selected from the displayed list of set
names.</font></p>
</div>
<h4>Prev command</h4>
<div style="margin-left: 2em">
<p><font size="2">Finds the previous member of a set. The first
time (or after a "no more records" message), <b>Prev</b> displays
the last member of the set. A <b>Last</b> or <b>Next</b> command
must have preceded the call to <b>Prev</b>.</font></p>
</div>
<h4>Connect command</h4>
<div style="margin-left: 2em">
<p><font size="2">Connects the current record to the current owner
of the set selected from the displayed list of set
names.</font></p>
</div>
<h4>Disconnect command</h4>
<div style="margin-left: 2em">
<p><font size="2">Disconnects the current record from the set
selected from the displayed list of set names.</font></p>
</div>
<h4>Total command</h4>
<div style="margin-left: 2em">
<p><font size="2">Displays a count of the members connected to the
current owner of the set selected from the displayed list of set
names.</font></p>
</div>
<h3>8.4.3 Using the Access Currency Commands</h3>
<p><font size="2">The <b>Currency</b> command, selected from the
<b>Database Access Commands</b> submenu, accesses the <b>Currency
Table Manipulation Functions</b> submenu (shown in Figure 8-14 and
followed by a description of its functions).</font></p>
<hr>
<div style="margin-left: 4em">
<pre>
<b><font color=
"#0000FF">Currency Table Manipulation Functions</font>
Owner  Member  Record  Auto_set  Display  Timestamp  X_exit</b>
</pre></div>
<hr>
<p align="center"><font size="2"><b>Fig. 8-14. Currency Table
Manipulation Functions Submenu</b></font></p>
<h4>Owner command</h4>
<div style="margin-left: 2em">
<p><font size="2">Sets the current owner of the set selected from
the displayed list of set names. This function then invokes the
<b>Change Current Owner of Set</b> submenu, from which you select
the record you wish to be made current. The submenu is shown in
Figure 8-15, followed by a description of its functions.</font></p>
</div>
<hr>
<div style="margin-left: 8em">
<pre>
<b><font color="#0000FF">Change Current Owner of Set</font>
Record  Owner  Member  Change  X_exit</b>
</pre></div>
<hr>
<p align="center"><font size="2"><b>Fig. 8-15. Change Current Owner
of Set Submenu</b></font></p>
<div style="margin-left: 4em">
<p>Record<br>
Changes the current owner of the selected set to the current
record.</p>
<p>Owner<br>
Changes the current owner of the previously selected set to the
current owner of the set selected from the displayed list of
sets.</p>
<p>Member<br>
Changes the current owner of the previously selected set to the
current member of the set selected from the displayed list of
sets.</p>
<p>Change<br>
Changes the current owner of the selected set to the database
address entered in response to the prompt:</p>
<pre>
<font color=
"#0000FF">enter database address: [</font><b><i><font color=
"#0000FF" size="1">f </font></i></b><font color=
"#0000FF">:</font><b><i><font color="#0000FF" size=
"1">r</font></i></b><font color="#0000FF">]</font>
</pre>
<p><font size="2">where <b><i>f</i></b> is the file number and
<b><i>r</i></b> is the record number. Refer to section 14.2.2,
"Data File Organization," for a description of database
addresses.</font></p>
</div>
<h4>Member command</h4>
<div style="margin-left: 2em">
<p><font size="2">Sets the current member of the set selected from
the displayed list of set names. It then invokes the <b>Change
Current Member of Set</b> submenu, shown in Figure 8-16, to
determine the record to be made current.</font></p>
</div>
<hr>
<div style="margin-left: 10em">
<pre>
<b><font color="#0000FF">Change Current Member of Set</font>
Record  Owner  Member  Change  X_exit</b>
</pre></div>
<hr>
<p align="center"><font size="2"><b>Fig. 8-16. Change Current
Member of Set Submenu</b></font></p>
<div style="margin-left: 4em">
<p>Record<br>
Changes the current member of the selected set to the current
record.</p>
<p>Owner<br>
Changes the current member of the previously selected set to the
current owner of the set selected from the displayed list of
sets.</p>
<p>Member<br>
Changes the current member of the previously selected set to the
current member of the set selected from the displayed list of
sets.</p>
<p>Change<br>
Changes the current member of the selected set to the database
address entered in response to the prompt:</p>
<pre>
<font color=
"#0000FF">enter database address: [<b><i>f</i> :</b>r</font>]
</pre>
<p><font size="2">where <b><i>f</i></b> is the file number and
<b><i>r</i></b> is the record number.</font></p>
</div>
<h4>Record command</h4>
<div style="margin-left: 2em">
<p><font size="2">Changes the current record. This selection
invokes the <b>Change Current Record</b> submenu, shown in Figure
8-17, to determine the record to be made current.</font></p>
</div>
<hr>
<div style="margin-left: 12em">
<pre>
<b><font color="#0000FF">Change Current Record</font>
Owner  Member  Change  X_exit</b>
</pre></div>
<hr>
<p align="center"><font size="2"><b>Fig. 8-17. Change Current
Record Submenu</b></font></p>
<div style="margin-left: 4em">
<p>Owner<br>
Changes the current record to the current owner of the set selected
from the displayed list of set names.</p>
<p>Member<br>
Changes the current record to the current member of the set
selected from the displayed list of set names.</p>
<p>Change<br>
Changes the current record to the database address entered in
response to the prompt:</p>
<pre>
<font color="#0000FF">enter database address: [<i>f :r</i>] </font>
</pre>
<p><font size="2">where <b><i>f</i></b> is the file number and
<b><i>r</i></b> is the record number.</font></p>
</div>
<h4>Auto_set command</h4>
<div style="margin-left: 2em">
<p><font size="2">Toggles the automatic set connection flag within
<b>ida</b>. When turned on, this flag causes newly entered records
to be connected automatically to the current owners of the sets for
which they are members.</font></p>
</div>
<h4>Display command</h4>
<div style="margin-left: 2em">
<p><font size="2">Displays the currency tables showing the record
type and database addresses of the current record and, for each
set, the current owner and current member of that set. It also
indicates whether automatic set connection is enabled.</font></p>
</div>
<h4>Timestamp command</h4>
<div style="margin-left: 2em">
<p><font size="2">Invokes the <b>Timestamp Currency Functions</b>
submenu, shown in Figure 8-18, for testing currency table timestamp