84 lines
1.6 KiB
Groff
84 lines
1.6 KiB
Groff
.TH record "" "" "/rdb Command"
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.PC "Find and output a record from a table"
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\fBrecord \fInumber \fB< \fItable\fR
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.PP
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.II "row^find r. by number"
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.II "find record by number"
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The command
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.B record
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searches through
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.I table
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for the record with the serial number
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.IR number .
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If it finds the record, it prints it and the table's header on the
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standard output.
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.SH Example
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To retrieve the third record from table
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.BR inventory ,
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type:
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.DM
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record 3 < inventory
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.DE
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.PP
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You will see something like the following:
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.DM
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Item Amount Cost Value Description
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---- ------ ---- ----- --------------
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3 5 80 400 clamps
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.DE
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.PP
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The following shell script uses
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.B record
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and
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.B read
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to find specific values in table
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.BR inventory .
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The command
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.B read
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uses the head line of
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.B inventory
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to assign values to each column name.
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.DM
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: describe - gives the description for an item in inventory
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USAGE='usage: describe Item < table'
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.sp \n(pDu
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record $1 < inventory |
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( read HEAD
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read DASH
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read $HEAD
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echo "Item $Item is $Description"
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)
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.DE
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.PP
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When you type
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.DM
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describe 1 < inventory
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.DE
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.PP
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you see output in the following format:
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.DM
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Item 1 is rubber gloves
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.DE
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.SH "Record Numbers"
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.I "(Ruby re-creation only.)"
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Records are counted from 1.
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The numbers 0 and 1 both mean the first record.
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A negative number counts from the end:
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.B \-1
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is the last record,
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.B \-2
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the one before it, and so on.
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A number beyond either end gives a table without records.
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Anything that is not a whole number is an error.
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.SH "See Also"
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.B
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row,
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search
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.R
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.br
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COHERENT Lexicon:
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.B
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read
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.R
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.SO record
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