I'm trying to remove lines of data that contain duplicate data in a specific column.
For example.
apple 12345
apple 54321
apple 14234
orange 55656
orange 88989
orange 99898
I only want to see
apple 12345
orange 55656
How would i go about doing this? (5 Replies)
hi,
I have a requirement where in I read the values from a file using awk. The resulting data should be converted into row format from column format.
For ex: My log file login.lst contains the following
SERVER1 DB1
SERVER2 DB2
SERVER3 DB3
SERVER4 DB4
I use awk to grep only the server... (6 Replies)
Hi All,
I needd to convert values in a row to a column.
eg: Input is as: value1,value2,value3,value4,.........,value N
Required Output:
Value1
Value2
Value3
.
.
.
Value N
Please help.... (3 Replies)
I am a newbie to shell scripting ..
I have a .csv file. It has 1000 some rows and about 7 columns...
but before I insert this data to a table I have to parse it and clean it ..basing on the value of the first column..which a string of phone number type...
example below..
column 1 ... (2 Replies)
Hello,
I am new to Linux environment , I working on Linux script which should send auto email based on the specific condition from log file. Below is the sample log file
Name m/c usage
abc xxx 10
abc xxx 20
abc xxx 5
xyz ... (6 Replies)
Dear Folks
Hello
I have a column of numbers, say:
26
79
68
I want to add one to each row value and get this desire column:
26
27
79
80
68
69 (6 Replies)
Dear folks
I have a map file of around 54K lines and some of the values in the second column have the same value and I want to find them and delete all of the same values. I looked over duplicate commands but my case is not to keep one of the duplicate values. I want to remove all of the same... (4 Replies)
Hi Experts,
Please bear with me, i need help
I am learning AWk and stuck up in one issue.
First point : I want to sum up column value for column 7, 9, 11,13 and column15 if rows in column 5 are duplicates.No action to be taken for rows where value in column 5 is unique.
Second point : For... (12 Replies)
I have a file with 5 columns. I want to pull out all records where the value in column 4 is not unique. For example in the sample below, I would want it to print out all lines except for the last two.
40991764 2419 724 47182 Cand A
40992936 3591 724 47182 Cand B
40993016 3671 724 47182 Cand C... (5 Replies)
Discussion started by: kaktus
5 Replies
LEARN ABOUT DEBIAN
bup-margin
bup-margin(1) General Commands Manual bup-margin(1)NAME
bup-margin - figure out your deduplication safety margin
SYNOPSIS
bup margin [options...]
DESCRIPTION
bup margin iterates through all objects in your bup repository, calculating the largest number of prefix bits shared between any two
entries. This number, n, identifies the longest subset of SHA-1 you could use and still encounter a collision between your object ids.
For example, one system that was tested had a collection of 11 million objects (70 GB), and bup margin returned 45. That means a 46-bit
hash would be sufficient to avoid all collisions among that set of objects; each object in that repository could be uniquely identified by
its first 46 bits.
The number of bits needed seems to increase by about 1 or 2 for every doubling of the number of objects. Since SHA-1 hashes have 160 bits,
that leaves 115 bits of margin. Of course, because SHA-1 hashes are essentially random, it's theoretically possible to use many more bits
with far fewer objects.
If you're paranoid about the possibility of SHA-1 collisions, you can monitor your repository by running bup margin occasionally to see if
you're getting dangerously close to 160 bits.
OPTIONS --predict
Guess the offset into each index file where a particular object will appear, and report the maximum deviation of the correct answer
from the guess. This is potentially useful for tuning an interpolation search algorithm.
--ignore-midx
don't use .midx files, use only .idx files. This is only really useful when used with --predict.
EXAMPLE
$ bup margin
Reading indexes: 100.00% (1612581/1612581), done.
40
40 matching prefix bits
1.94 bits per doubling
120 bits (61.86 doublings) remaining
4.19338e+18 times larger is possible
Everyone on earth could have 625878182 data sets
like yours, all in one repository, and we would
expect 1 object collision.
$ bup margin --predict
PackIdxList: using 1 index.
Reading indexes: 100.00% (1612581/1612581), done.
915 of 1612581 (0.057%)
SEE ALSO bup-midx(1), bup-save(1)BUP
Part of the bup(1) suite.
AUTHORS
Avery Pennarun <apenwarr@gmail.com>.
Bup unknown-bup-margin(1)