I have a file called DB_create.sql which has this line
CREATE DATABASE testrepo;
I want to extract only testrepo from this. So I've tried
cat DB_create.sql | awk '{print $3}'
This gives me testrepo;
I need only testrepo. How do I get this ?
With your shown samples, please try following.
awk -F'[ ;]' '{print $(NF-1)}' DB_create.sql
OR
awk -F'[ ;]' '{print $3}' DB_create.sql
OR without setting any field separators try:
awk '{sub(/;$/,"");print $3}' DB_create.sql
Simple explanation would be: making field separator as space OR semi colon and then printing 2nd last field($NF-1) which is required by OP here. Also you need not to use cat command with awk because awk can read Input_file by itself.
Using gnu awk, you can set record separator as ; + line break:
awk -v RS=';\r?\n' '{print $3}' file.sql
testrepo
Or using any POSIX awk, just do a call to sub to strip trailing ;:
awk '{sub(/;$/, "", $3); print $3}' file.sql
testrepo
You can use
awk -F'[;[:space:]]+' '{print $3}' DB_create.sql
where the field separator is set to a [;[:space:]]+ regex that matches one or more occurrences of ; or/and whitespace chars. Then, Field 3 will contain the string you need without the semi-colon.
More pattern details:
[ - start of a bracket expression
; - a ; char
[:space:] - any whitespace char
] - end of the bracket expression
+ - a POSIX ERE one or more occurrences quantifier.
See the online demo.
Use your own code but adding the function sub():
cat DB_create.sql | awk '{sub(/;$/, "",$3);print $3}'
Although it's better not using cat. Here you can see why: Comparison of cat pipe awk operation to awk command on a file
So better this way:
awk '{sub(/;$/, "",$3);print $3}' file
Related
I have some text I need to split up to extract the relevant argument, and my [g]awk match command does not behave - I just want to understand why?! (I have written a less elegant way around it now...).
So the string is blahblah|msgcontent1=HeaderUUIiewConsenFlagPSMessage|msgtype2=Blah002|msgcontent2=header
I want to output just the contents of msgcontent1=, so did
echo "blahblah|msgcontent1=HeaderUUIiewConsenFlagPSMessage|msgtype2=Blah002|msgcontent2=header" | gawk '{ if (match($0,/msgcontent1=(.*)[|]/,a)) { print a[1]; } }'
Trouble instead of getting
HeaderUUIiewConsenFlagPSMessage
I get the match with everything from there to the last pipe of the string HeaderUUIiewConsenFlagPSMessage|msgtype2=Blah002
Now I accept this is because the regexp in /msgcontent1=(.*)[|]/ can match multiple ways, but HOW do I make it match the way I want it to??
With your shown samples please try following. Written and tested in GNU awk this will print only contents from msgcontent1= till | first occurrence.
awk 'match($0,/msgcontent1=[^|]*/){print substr($0,RSTART+12,RLENGTH-12)}' Input_file
OR with echo + awk try:
echo "blahblah|msgcontent1=HeaderUUIiewConsenFlagPSMessage|msgtype2=Blah002|msgcontent2=header" |
awk 'match($0,/msgcontent1=[^|]*/){print substr($0,RSTART+12,RLENGTH-12)}'
With FPAT option in GNU awk:
awk -v FPAT='msgcontent1=[^|]*' '{sub(/.*=/,"",$1);print $1}' Input_file
This is your input:
s='blahblah|msgcontent1=HeaderUUIiewConsenFlagPSMessage|msgtype2=Blah002|msgcontent2=header'
You may use gnu awk like this to extract value after msgcontent1=:
awk -F= -v RS='|' '$1 == "msgcontent1" {print $2}' <<< "$s"
HeaderUUIiewConsenFlagPSMessage
or using this sed:
sed -E 's/^(.*\|)?msgcontent1=([^|]+).*/\2/' <<< "$s"
HeaderUUIiewConsenFlagPSMessage
Or using this gnu grep:
grep -oP '(^|\|)msgcontent1=\K[^|]+' <<< "$s"
HeaderUUIiewConsenFlagPSMessage
echo "blahblah|msgcontent1=HeaderUUIiewConsenFlagPSMessage|msgtype2=Blah002|msgcontent2=header" | awk '{ if (match($0,/msgcontent1=([^\|]*)/,a)) print a[1] }'
this prints HeaderUUIiewConsenFlagPSMessage
The reason your regex match msgcontent1=HeaderUUIiewConsenFlagPSMessage|msgtype2=Blah002 is that matching is 'hungry' so it allways finds the longest possible match
Also with awk:
echo 'blahblah|msgcontent1=HeaderUUIiewConsenFlagPSMessage|msgtype2=Blah002|msgcontent2=header' | awk -v FS='[=|]' '$2 == "msgcontent1" {print $3}'
HeaderUUIiewConsenFlagPSMessage
I have the following sentence within a file
FQDN=joe.blogs.com.
How can I print the string "joe"
I have tried using -->> awk -F"=" '{print $2}' file
but this returns joe.blogs.com as "=" is the delimiter.
Is it possible to use 2 delimiters on the same line?
You might use regular expression as FS. Let file.txt content be
FQDN=joe.blogs.com.
then
awk 'BEGIN{FS="[=.]"}{print $2}' file.txt
output
joe
In case you are ok with sed, could you please try following.
sed 's/.*=\([^.]*\)\..*/\1/' Input_file
With GNU grep and using its -oP flag we could try following too.
grep -oP '(.*=)\K([^.]*)' Input_file
You could use GNU grep:
grep -oP '(?<=FQDN=)[^.]+' file
^ all characters up to a '.'
^ lookbehind for 'FQDN='
^ only print match and Perl style regex
Or with Perl:
perl -lne 'print $1 if /(?<=FQDN=)([^.]+)/' file
With awk I would probably do:
awk 'BEGIN{FS="[.=]"} /FQDN=/{print $2}' file
why not keeping it simple and pipe awk?
awk -F"=" '{print $2}' | awk -F"." '{print $1}'
can I use two field delimiters on one line?
No. You may do further string manipulation as post processing, or you could use a regex as field delimiter.
Another option is to use awk's split function:
awk -F= '{ split($2,map,".");print map[1] }' file
Split the second = separated field into the array map using "." as the delimiter. Print the first index of the array.
I have a file input.txt which stores information in KEY:VALUE form. I'm trying to read GOOGLE_URL from this input.txt which prints only http because the seperator is :. What is the problem with my grep command and how should I print the entire URL.
SCRIPT
$> cat script.sh
#!/bin/bash
URL=`grep -e '\bGOOGLE_URL\b' input.txt | awk -F: '{print $2}'`
printf " $URL \n"
INPUT_FILE
$> cat input.txt
GOOGLE_URL:https://www.google.com/
OUTPUT
https
DESIRED_OUTPUT
https://www.google.com/
Since there are multiple : in your input, getting $2 will not work in awk because it will just give you 2nd field. You actually need an equivalent of cut -d: -f2- but you also need to check key name that comes before first :.
This awk should work for you:
awk -F: '$1 == "GOOGLE_URL" {sub(/^[^:]+:/, ""); print}' input.txt
https://www.google.com/
Or this non-regex awk approach that allows you to pass key name from command line:
awk -F: -v k='GOOGLE_URL' '$1==k{print substr($0, length(k FS)+1)}' input.txt
Or using gnu-grep:
grep -oP '^GOOGLE_URL:\K.+' input.txt
https://www.google.com/
Could you please try following, written and tested with shown samples in GNU awk. This will look for string GOOGLE_URL and will catch further either http or https value from url, in case you need only https then change http[s]? to https in following solution please.
awk '/^GOOGLE_URL:/{match($0,/http[s]?:\/\/.*/);print substr($0,RSTART,RLENGTH)}' Input_file
Explanation: Adding detailed explanation for above.
awk ' ##Starting awk program from here.
/^GOOGLE_URL:/{ ##Checking condition if line starts from GOOGLE_URL: then do following.
match($0,/http[s]?:\/\/.*/) ##Using match function to match http[s](s optional) : till last of line here.
print substr($0,RSTART,RLENGTH) ##Printing sub string of matched value from above function.
}
' Input_file ##Mentioning Input_file name here.
2nd solution: In case you need anything coming after first : then try following.
awk '/^GOOGLE_URL:/{match($0,/:.*/);print substr($0,RSTART+1,RLENGTH-1)}' Input_file
Take your pick:
$ sed -n 's/^GOOGLE_URL://p' file
https://www.google.com/
$ awk 'sub(/^GOOGLE_URL:/,"")' file
https://www.google.com/
The above will work using any sed or awk in any shell on every UNIX box.
I would use GNU AWK following way for that task:
Let file.txt content be:
EXAMPLE_URL:http://www.example.com/
GOOGLE_URL:https://www.google.com/
KEY:GOOGLE_URL:
Then:
awk 'BEGIN{FS="^GOOGLE_URL:"}{if(NF==2){print $2}}' file.txt
will output:
https://www.google.com/
Explanation: GNU AWK FS might be pattern, so I set it to GOOGLE_URL: anchored (^) to begin of line, so GOOGLE_URL: in middle/end will not be seperator (consider 3rd line of input). With this FS there might be either 1 or 2 fields in each line - latter is case only if line starts with GOOGLE_URL: so I check number of fields (NF) and if this is second case I print 2nd field ($2) as first record in this case is empty.
(tested in gawk 4.2.1)
Yet another awk alternative:
gawk -F'(^[^:]*:)' '/^GOOGLE_URL:/{ print $2 }' infile
By running the following I am getting as a result the string "utf-8"
I thought that with this command I would had string "tralala" returned
echo "=?utf-8?B?tralala" | awk -F "?B?" '{print $2 }'
Why is that?
What delimiter should I use in order to get the string "tralala" ?
? is a regex metacharacter that means zero or one matches of the preceding atom. (I'm surprised awk didn't complain about the one at the start but .)
Try echo "=?utf-8?B?tralala" | awk -F '\\?B\\?' '{print $2 }' instead.
Awk delimiters are NOT strings, they are "Field Separators" (hence the variable named FS) which are a type of Extended Regular Expression with some additional features (e.g. a single blank char as the field separator when not inside square brackets means separate by all chains of contiguous white space and ignore leading and trailing white space on each record).
The difference between a string, a regular expression, and a field separator are very important to be aware of. You sometimes also see the word "pattern" used - do not use that term, it has no (or too many possible) meaning.
A ? is an RE metacharacter so you need to tell awk not to treat it as such in your case by either of these methods:
$ echo "=?utf-8?B?tralala" | awk -F '[?]B[?]' '{print $2}'
tralala
$ echo "=?utf-8?B?tralala" | awk -F '\\?B\\?' '{print $2}'
tralala
You don't strictly need to do that for the first ? as it's metacharacter functionality is not applicable when it's the first char in an RE:
$ echo "=?utf-8?B?tralala" | awk -F '?B[?]' '{print $2}'
tralala
$ echo "=?utf-8?B?tralala" | awk -F '?B\\?' '{print $2}'
tralala
but IMHO it's best to do it anyway for clarity and future-proofing.
I'm trying different commands to process csv file where the separator is the pipe | character.
While those commands do work when the comma is a separator, it throws an error when I replace it with the pipe:
awk -F[|] "NR==FNR{a[$2]=$0;next}$2 in a{ print a[$2] [|] $4 [|] $5 }" OFS=[|] file1.csv file2.csv
awk "{print NR "|" $0}" file1.csv
I tried, "|", [|], /| to no avail.
I'm using Gawk on windows. What I'm I missing?
You tried "|", [|] and /|. /| does not work because the escape character is \, whereas [] is used to define a range of fields, for example [,-] if you want FS to be either , or -.
To make it work "|" is fine, are you sure you used it this way? Alternativelly, escape it --> \|:
$ echo "he|llo|how are|you" | awk -F"|" '{print $1}'
he
$ echo "he|llo|how are|you" | awk -F\| '{print $1}'
he
$ echo "he|llo|how are|you" | awk 'BEGIN{FS="|"} {print $1}'
he
But then note that when you say:
print a[$2] [|] $4 [|] $5
so you are not using any delimiter at all. As you already defined OFS, do:
print a[$2], $4, $5
Example:
$ cat a
he|llo|how are|you
$ awk 'BEGIN {FS=OFS="|"} {print $1, $3}' a
he|how are
For anyone finding this years later: ALWAYS QUOTE SHELL METACHARACTERS!
I think gawk (GNU awk) treats | specially, so it should be quoted (for awk). OP had this right with [|]. However [|] is also a shell pattern. Which in bash at least, will only expand if it matches a file in the current working directory:
$ cd /tmp
$ echo -F[|] # Same command
-F[|]
$ touch -- '-F|'
$ echo -F[|] # Different output
-F|
$ echo '-F[|]' # Good quoting
-F[|] # Consistent output
So it should be:
awk '-F[|]'
# or
awk -F '[|]'
awk -F "[|]" would also work, but IMO, only use soft quotes (") when you have something to actually expand (or the string itself contains hard quotes ('), which can't be nested in any way).
Note that the same thing happens if these characters are inside unquoted variables.
If text or a variable contains, or may contain: []?*, quote it, or set -f to turn off pathname expansion (a single, unmatched square bracket is technically OK, I think).
If a variable contains, or may contain an IFS character (space, tab, new line, by default), quote it (unless you want it to be split). Or export IFS= first (bearing the consequences), if quoting is impossible (eg. a crazy eval).
Note: raw text is always split by white space, regardless of IFS.
Try to escape the |
echo "more|data" | awk -F\| '{print $1}'
more
You can escape the | as \|
$ cat test
hello|world
$ awk -F\| '{print $1, $2}' test
hello world