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Shell Programming and Scripting

fgrep command

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# 8  
Old 12-23-2009
All the Commands are working fine.But the problem is , the commands are taking huge time when the files have records around 5M
# 9  
Old 12-23-2009
How long does it take exactly?
# 10  
Old 12-23-2009
Code:
#!/bin/sh

PATTERNS=`cat patternfile`

for pat in $PATTERNS
do
cat File2 | grep "^$pat\>"
done

this command is fine . but the problem is this is very slow if have millions records

---------- Post updated at 08:17 AM ---------- Previous update was at 08:11 AM ----------

the above command is very slow if we have millions of records in the file
Last edited by pludi; 12-23-2009 at 09:18 AM.. Reason: code tags, please...
# 11  
Old 12-23-2009
Quote:
Originally Posted by morbid_angel
Code:
#!/bin/sh

PATTERNS=`cat patternfile`

for pat in $PATTERNS
do
cat File2 | grep "^$pat\>"
done

this command is fine . but the problem is this is very slow if have millions records

---------- Post updated at 08:17 AM ---------- Previous update was at 08:11 AM ----------

the above command is very slow if we have millions of records in the file

Why are you using cat?
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