97 lines
2.0 KiB
Groff
97 lines
2.0 KiB
Groff
.TH delete "" "" "/rdb Command"
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.PC "Blank record and update index file"
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\fBdelete [-m[bhirs]] \fItable keycolumn ... \fB< \fIkeytable\fR
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.PP
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.II row^delete
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.II "delete row"
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The command
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.B delete
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writes a blank record on the row in
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.I table
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whose key matches the row in the
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.IR keytable .
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It also deletes the offset row in the appropriate fast-access
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offset table, or, in the case of the
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.B hash
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method, replaces the deleted offset with \-1.
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.PP
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Options
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.B \-m[bhirs]
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lets you select a type of fast-accessing to locate the row to delete.
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For information on the type of fast accessing that each option invokes,
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see the manual entry for
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.BR index .
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.SH Example
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Consider table
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.BR inventory ,
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which appears as follows:
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.DM
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Item Amount Cost Value Description
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---- ------ ---- ----- --------------
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1 3 50 150 rubber gloves
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2 100 5 500 test tubes
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3 5 80 400 clamps
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4 23 19 437 plates
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5 99 24 2376 cleaning cloth
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6 89 147 13083 bunsen burners
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7 5 175 875 scales
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.DE
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.PP
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The
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.B record
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index looks like this:
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.DM
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Offset
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--------
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76
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113
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147
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177
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207
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245
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283
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.DE
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.PP
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The following command deletes the first record
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.BR Item 1:
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.DM
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echo 1 | delete -mr inventory Item
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.DE
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.PP
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.B inventory
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now appears as follows:
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.DM
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Item Amount Cost Value Description
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---- ------ ---- ----- --------------
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2 100 5 500 test tubes
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3 5 80 400 clamps
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4 23 19 437 plates
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5 99 24 2376 cleaning cloth
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6 89 147 13083 bunsen burners
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7 5 175 875 scales
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.DE
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.PP
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.B inventory.r
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now appears as follows:
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.DM
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Offset
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--------
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113
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147
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177
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207
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245
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283
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.DE
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.PP
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Note that we have blanked out the record and removed the
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offset.
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.SH "See Also"
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.B
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append,
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index,
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replace
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.R
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.SO delete
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