Hello all.
Sorry, I know this question is similar to many others, but I just can seem to put together exactly what I need.
My file is tab delimitted and contains approximately 1 million rows. I would like to send lines 1,4,& 7 to a file. Lines 2, 5, & 8 to a second file. Lines 3, 6, & 9 to... (11 Replies)
I have a file containing about 5 million rows, in the file there are some records which has extra delimiter at random position. (we dont know the positions), now we have to Count the delimeter from each row and if the count of delimeter is not matching then I want to delete those rows from the... (5 Replies)
I have a SQL query
SELECT
BLAH_ID,
BLAH_CODE,
DATEFORMAT(CALENDAR_DATE, 'MM-DD-YYYY') AS CALENDAR_DATE_STR,
HOURS,
'N',
FROM blah_tmp_tbl order by CALENDAR_DATE_STR,BLAH_ID,BLAH_CODE;
OUTPUT TO 'MyExport.CSV' quote '' FORMAT ASCII;
That gets me the below output;
... (2 Replies)
Hello,
Working on a ksh script and a little stumped... how can I return all characters to the left of the last delimeter per line in a file, skipping any lines without that delimeter?
ie, sample.txt:
Once_upon-a-Midnight_dreary_while
I pondered, weak_and weary
over many a quaint
and... (4 Replies)
My TSV looks like:
Hello my name is John \t Hello world \t Have a good day! \t See you later!
Is there a simple bash script that splits the tsv on tab to:
Hello my name is John
Hello world
Have a good day!
See you later!
I'm really stuck, would appreciate any help! (5 Replies)
I have a very large csv file that I sort by the data that is in the second column. But what I need to do next is split the file in groups of say around 30,000 lines but don't split the data while there is still like data in the in the second column.
Here is some of the data.
... (2 Replies)
Hi
i have requirement like below
M <form_name> sdasadasdMklkM
D ......
D .....
M form_name> sdasadasdMklkM
D ......
D .....
D ......
D .....
M form_name> sdasadasdMklkM
D ......
M form_name> sdasadasdMklkM
i want split file based on line number by finding... (10 Replies)
Hi All,
Greetings everyone !!!
I have a file which has many lines, out of which one line is as below.
I need to search for pattern "varchar(30) Select" and if exists, then split the line as below.
I am trying to achieve this in ksh. Can anyone help me on this. (8 Replies)
I have to split a file containing 100 lines to 5 files say from lines ,1-20 ,21-30 ,31-40 ,51-60 ,61-100
Here is i can do it for 2 file but how to handle it for more than 2 files
awk 'NR < 21{ print >> "a"; next } {print >> "b" }' $input_file
Please advidse.
Thanks (4 Replies)
Discussion started by: abhaydas
4 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)