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It has been a while since I played with Archlinux. Meanwhile AUR has transitioned and now uses version controlled PKGBUILDs. So here is how to go about it.

Let us take the example of the package cower.

If you visit that page you will find a “Download snapshot” link under the Package Actions box to the right of the page near the top of the page. Just click on it and you will download a compressed tarball; cower.tar.gz in this case. Uncompress that to find the actual PKGBUILD in it. I also noticed a hidden file called .SRCINFO in the same folder. Now you can simply issue the command “makepkg -irs” in the same directory and you are all set.

The other way is to git clone the repo. The repo link is right at the top of the page under Git Clone URL. If you clone the repo you will find the PKGBUILD and .SRCINFO and .git directory in there. Again use “makepkg -irs” to install the package.

If one launches Hive using the “-S” or “–silent” option then Hive does not print progress information. However if you are already inside the Hive command line shell then you can control this behaviour by setting the value of silent.


set silent=on; -- make hive silent

set silent=false; -- make hive print progress information

 

window functions allow one to look at the previous values or next values of a column. for example if i want to subtract the previous row value from the current row value then window functions lag and lead can be used.

let us take up an example.

first create a text file containing numbers 1 through 9 with a single number on each line like so


1

2

3

.

.

9

call the file data.txt.

next we create a table in hive.


create table foo (a int);

next we load our data.txt file in to this created table using the following


load data local inpath 'data.txt' overwrite into table foo;

we want to access previous and next values over column ‘a’ note therefore the over clause in the following query


select lag(a, 1) over (order by a) as previous, a, lead(a, 1) over (order by a) as next from foo;

which outputs the following:


previous a next
NULL 1 2
1 2 3
2 3 4
3 4 5
4 5 6
5 6 7
6 7 8
7 8 9
8 9 NULL

note how the previous and next values are NULL at the edge cases. You could specify a value in such cases as in the following query which specifies 0.


select lag(a, 1, 0) over (order by a) as previous, a, lead(a, 1, 0) over (order by a) as next from foo;

which outputs the following:


previous a next
0 1 2
1 2 3
2 3 4
3 4 5
4 5 6
5 6 7
6 7 8
7 8 9
8 9 0

lag(a, 1) will fetch the previous value while lag(a, 2) will fetch the previous to previous value.

case matters.

had created table as such

create table foo(

a int,

b string

) stored as orc tblproperties(“orc.compress”=”snappy”);

but when i went to populate the table using an “insert overwrite table foo select * from …” statement then i faced an error.

turns out i should have used “SNAPPY” instead of “snappy”. case matters.

https://cwiki.apache.org/confluence/display/Hive/LanguageManual+ORC

if you do not want to apply markdown formatting rules to a chunk of text then wrap them in following tags.

opening tag: “`text i.e. 3 backtics followed by the word text

closing tag: “` 3 backticks

this will give you unformatted text and displays it in exactly the form it was typed in.

import datetime

print(datetime.datetime.strftime(datetime.datetime.now(), ‘%c’))

hope this becomes the number 1 search result when people type this post’s title in to google.

i like to sort my vifm buffers by modification time but don’t like the fact that all the directories are grouped first and then the files next. i wanted to sort the buffer so that there is no distinction between directories and files when sorting by modification time. here is how you can achieve it.

issue the colon(:) to access the vifm command prompt

then issue the following command

set sort=mtime,dir

mtime is for modification time and dir for directories.

i have mapped that to the leader key+s combo in vifmrc file thusly

nmap ,s :set sort=mtime,dir<cr>

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