converting date format

Shell Programming and Scripting
1

Hi

Please anyone to help to write script to convert date to 'yyyy-mm-dd'(If column is date convert) because my file has large and lot of date colums.

If file is small ,using awk command to achive.

cat file1|awk 'BEGIN {FS=OFS='|'} {$1=substr($1,1,4)"-"substr($1,5,2)"-"substr($1,7,2);{$2=substr($2,1,4)"-"substr($2,5,2)"-"substr($2,7,2);print $0}'

Thanks,
MR

2

Please provide an example of part of your file.

3

Hi,

Sample data
99990101|20080331|0.0000000|FBF7.375 12/09|0.0000000|20070809|20080908|0.0000000|12/09|.....

Thanks
MR

4

This should give you a boost.

awk 'BEGIN {FS=OFS="|"} {for (i=1;i<=NF;i++) if (length($i)==8) $i=substr($i,1,4)"-"substr($i,5,2)"-"substr($i,7,2);print }' file1
5

Hi danmero,

Thanks ,This is what I am looking for.

Thanks,
MR

6

Hi danmero

How it can be handled If any othey colum that having length of 8 other than date columns ? (Is there any command to validate the date ).In that case it will take the columns data and convert to date format

Thanks,
MR

7

Yes, you can validate the date if you know the date range, here is a basic example:

awk 'BEGIN {FS=OFS="|"} {for (i=1;i<=NF;i++) if ($i ~ /[1-2][0-9][0-9][0-9][0-1][0-9][0-3][0-9]/) $i=substr($i,1,4)"-"substr($i,5,2)"-"substr($i,7,2);print }' file1
8

Hi danmero,

Thanks for your prompt reply

Thanks ,
MR