Login or Register to Ask a Question and Join Our Community


Shell Programming and Scripting

For loop

Login to Discuss or Reply to this Discussion in Our Community

 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting For loop
# 1  
Old 06-16-2010
For loop
Hi All ,
Am writing a script to apply one command on a long list of parameters that exists in a .txt file ,but it does'nt work for the moment , what am doing is :

Code:
#! /bin/bash
cd /ect/backup
rm -f output.sql
        for  i in list.txt
        do
        echo "update trbt_subscriber set cstcst_typ ='1' where telephonenumber = '$i' ;"  > output.sql
        done
        echo "commit ;" >> output.sql


thanks in advance .
Ibrahim
Last edited by radoulov; 06-16-2010 at 11:04 AM.. Reason: Please use code tags!
# 2  
Old 06-16-2010
Hi.

Are you trying to update a single column with a value called list.txt?

Code:
for i in list.txt

I guess not.

Can you show some of list.txt. You might be better with a while loop than a for loop.

Plus, you need an extra > :

Code:

echo "update trbt_subscriber set cstcst_typ ='1' where telephonenumber = '$i' ;" >> output.sql

Code:
rm -f output.sql
while read i; do
  echo "update trbt_subscriber set cstcst_typ ='1' where telephonenumber = '$i' ;"  >> output.sql
done < list.txt
echo "commit ;" >> output.sql

# 3  
Old 06-16-2010
I suppose you need:

Code:
sed "s/.*/update trbt_subscriber set cstcst_typ ='1' where telephonenumber = '&';\\
commit;/" list.txt > output.sql

# 4  
Old 06-16-2010
There are a few things that might not be what you want, if this code is really what you're running.

Code:
cd /ect/backup

That probably should be "/etc/" not "/ect"

Code:
for i in list.txt

That will merely cause the replacement of $i with "list.txt". You probably want to use something like

Code:
for i in `cat list.txt`

instead, to read the contents of the list.txt file.

Code:
echo "update trbt_subscriber set cstcst_typ ='1' where telephonenumber = '$i' ;" > output.sql

this will overwrite the output.sql file with each pass. Change the '>' to '>>'.

So, in total:

Code:
cd /etc/backup
rm -f output.sql
for i in `cat list.txt`
do 
echo "update trbt_subscriber set cstcst_typ = '1' where telephonenumber = '$i' ;" >> output.sql
done
echo "commit;" >> output.sql

# 5  
Old 06-16-2010
Quote:
Originally Posted by malcolmpdx
Code:
for i in `cat list.txt`

instead, to read the contents of the list.txt file.
But only if there are no whitespace(s) in the numbers.
# 6  
Old 06-16-2010
thanks a million for all of you ,
actually the ideas of malcolmpdx & scottn have idealy worked ,
but i have a small question for you scottn if you please :

- what "done < list.txt" is making ?
- how i can decide to use while or for my scripts ?

thanks in advance .
Ibrahim .
# 7  
Old 06-16-2010
Quote:
Originally Posted by engkemo2002
Hi All ,
Am writing a script to apply one command on a long list of parameters that exists in a .txt file ,but it does'nt work for the moment , what am doing is :

Code:
#! /bin/bash
cd /ect/backup
rm -f output.sql
        for  i in list.txt
        do
        echo "update trbt_subscriber set cstcst_typ ='1' where telephonenumber = '$i' ;"  > output.sql
        done
        echo "commit ;" >> output.sql


thanks in advance .
Ibrahim
can you try like this ?

Code:
#! /bin/bash
cd /ect/backup
rm -f output.sql

for i in `cat list | sed 's/ /_/'`; do a=$( (echo $i | sed 's/_/ / ') ) 
 echo "update trbt_subscriber set cstcst_typ ='1' where telephonenumber = '$a' ;"  >> output.sql
        done
        echo "commit ;" >> output.sql



---------- Post updated at 06:04 PM ---------- Previous update was at 05:49 PM ----------
Quote:
Originally Posted by engkemo2002
thanks a million for all of you ,
actually the ideas of malcolmpdx & scottn have idealy worked ,
but i have a small question for you scottn if you please :

- what "done < list.txt" is making ?
- how i can decide to use while or for my scripts ?

thanks in advance .
Ibrahim .
1- ) done<list.txt stdinput redirect to list.tx file in your script
so read command wait a input from stdinput but in this scenerio reads values in file instead of stdinput
2-) you can use usually more than elements variables in [for]
[while] is more effective and use for conditions
Last edited by ygemici; 06-16-2010 at 11:59 AM..
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

For loop or while loop from a text file

Hi all, i developed a script to measure the uptime of a process in a Solaris 10/11 environments. All is well, but i came across a situation where there are multiple processes of the same name. Basically i have the following result file: beVWARS 13357 19592122 beVWARS 14329 19591910... (4 Replies)
Discussion started by: nms
4 Replies

2. Shell Programming and Scripting

awk loop using array:wish to store array values from loop for use outside loop

Here's my code: awk -F '' 'NR==FNR { if (/time/ && $5>10) A=$2" "$3":"$4":"($5-01) else if (/time/ && $5<01) A=$2" "$3":"$4-01":"(59-$5) else if (/time/ && $5<=10) A=$2" "$3":"$4":0"($5-01) else if (/close/) { B=0 n1=n2; ... (2 Replies)
Discussion started by: klane
2 Replies

3. Shell Programming and Scripting

Reset while loop to loop same file multiple times

Hi, I want to read file multiple times. Right now i am using while loop but that is not working. ex. While read line do while read line2 do echo stmt1 #processing some data based on data., done < file2.txt done < file1.txt # This will have 10... (4 Replies)
Discussion started by: tmalik79
4 Replies

4. Shell Programming and Scripting

Array Variable being Assigned Values in Loop, But Gone when Loop Completes???

Hello All, Maybe I'm Missing something here but I have NOOO idea what the heck is going on with this....? I have a Variable that contains a PATTERN of what I'm considering "Illegal Characters". So what I'm doing is looping through a string containing some of these "Illegal Characters". Now... (5 Replies)
Discussion started by: mrm5102
5 Replies

5. Shell Programming and Scripting

My for loop decides to become an infinite loop?

Hi, I was debating if I should put this in the dummies or scripts section, I apologize in advance if I chose poorly. Fairly new to Unix and BASH scripting but I thought I made it fairly well given my limited understanding. However, the output indicates that it's looping and I'm ending up with a... (5 Replies)
Discussion started by: gotreef
5 Replies

6. Shell Programming and Scripting

S# in a for loop - concatenate $(loop counter)

Hi, hope I am posting in the right section. My problem is that I have 2 or more arguments passed and I want to check if the arguments passed exists or not. The first argument should not exist and the remaining others should exist. example: ./shells.sh argument1 argument2 argument3 ... (5 Replies)
Discussion started by: fight4love
5 Replies

7. Shell Programming and Scripting

BASH loop inside a loop question

Hi all Sorry for the basic question, but i am writing a shell script to get around a slightly flaky binary that ships with one of our servers. This particular utility randomly generates the correct information and could work first time or may work on the 12th or 100th attempt etc !.... (4 Replies)
Discussion started by: rethink
4 Replies

8. Shell Programming and Scripting

Null Handling in Until loop. . .loop won't stop

Hi Im running this script, which is supposed to find the max value build some tables and then stop running once all the tables are built. Thing is , it keeps assigning a null value to $h and then $g is null so it keep building tables i.e. testupdateNUL. How can I stop this? Here is what I have: ... (4 Replies)
Discussion started by: brandono66
4 Replies

9. Shell Programming and Scripting

Using variables created sequentially in a loop while still inside of the loop [bash]

I'm trying to understand if it's possible to create a set of variables that are numbered based on another variable (using eval) in a loop, and then call on it before the loop ends. As an example I've written a script called question (The fist command is to show what is the contents of the... (2 Replies)
Discussion started by: DeCoTwc
2 Replies

10. Shell Programming and Scripting

Is there a better way I could have run this loop. (For loop with two variables)

Sorry for such a dreadful title, but I'm not sure how to be more descriptive. I'm hoping some of the more gurutastic out there can take a look at a solution I came up with to a problem, and advice if there are better ways to have gone about it. To make a long story short around 20K pieces of... (2 Replies)
Discussion started by: DeCoTwc
2 Replies
Login or Register to Ask a Question