Sinclair QL User Manual page 333

CHAPTER 4
EXAMINING
A FILE
The best way to start learning about Archive IS to look through the demonstration file
gazet, provided on the Archive cartridge. This is a file which contains information about
various countries - the continent, the capital, the currency, the language, the population,
the land area and the gross domestic product per capita.
Most of the examples in chapters 4 and 5 refer to the "gazet" file. Before using
11,
you
should make a copy of It uSing the following procedure:
When you have loaded Archive, put a formatted cartridge into M,crodrlve 2 and type:
backup I ENTERI
mdv1_gazet_dbf
I
ENTER
I
mdv2_gazet_dbf
I
ENTER
I
Wait until the two Microdrives have stopped; be patient as the file is qUite long and can
take a while to copy. Use the copy, now on the cartridge in M,crodrlve 2, for
experimenting.
From now on we will not always write ENTER at the end of every command but please
remember that it must still be used.
The look command opens a file so that you may read ItS contents, but you are not able
to make alterations or additions to the file. It IS a safer command than open if you are
merely looking through a file because the file IS protected against accidental modification.
You can examine the copy of the 'gazet" file on Microdrive 2 by typing:
Look " gaz et ll
e
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DISPLAYING
ARECORD
To look at the first record type
- which displays the previous record,
~
which displays the first record,
- which shows the last record of the file.
6
EXAMINING
OTHER RECORDS
SEARCHING A
FILE
Find
f; rst
display
Don't forget to type ENTER alter each command and then the display will show the
first record of the file.
Note the first line shows the logical name of the file; Archive automatically supplies the
name "main" for a single file. Logical file names are usually used when you are using
more than one file at a time and are described later
Having looked at the first record of the file, you may want to move on to the following
record. Type:
next
and the display shows the next record In fhe file. When you are typing single commands
alter a display command the display area is continuously updated to show the contents
of the current record. You can use the next command to step through the file, record
by record until you reach the end (it will not pass the last record).
There are three other related commands which you can use to control which record
of the file is displayed.
back
first
last
Try uSing these commands to move around the file, displaying any record you like. Note
that the four commands first, last, next and back do not themselves display the record.
They merely move from record to record regardless of whether or not you have used
display command.
The first and Simplest search command is find. This will search from the beginning of
a file, looking for the first occurrence of a specified piece of text in any of the text fields.
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