Shell Programming and Scripting

Hi I have a problem with a sed script to change oracle sqlldr ctl files
I need to change a decode statement which works if there is only on occourance in a file if there are more it only chages the last one. how do I process all and the write the file out
------------------------------------------------
set -vx
CTL=`grep to_date *.ctl | grep decode | cut -f1 -d':'`
echo $CTL
for i in $CTL
do
COL=`grep to_date $i | grep decode | awk '{print $1}' | cut -f1 -d":"`
echo $COL
for n in $COL
do
FROM="decode(substr(:$n,2,1),' ',null,to_date(:"$n", 'dd/mm/yyyy')"
TO="to_date(decode(substr(:$n,2,1),' ',null,:$n),'dd/mm/rrrr')"
sed 's!'"$FROM"'!'"$TO"'!' $i > $i.out
done
done
------------------------------------------------------------
data.ctl
---------------options (errors=99)
load data
infile 'DATA.TXT'
append
into table TEST
fields terminated by ','
(
FSTCLN_DOB "decode(substr(:FSTCLN_DOB,2,1),' ',null,to_date(:FSTCLN_DOB, 'dd/mm/yyyy'))",
FSTCLN_BOB "decode(substr(:FSTCLN_BOB,2,1),' ',null,to_date(:FSTCLN_BOB, 'dd/mm/yyyy'))",
)

try this

Code:

FROM="decode(substr(:${n},2,1),' ',null,to_date(:"${n}", 'dd/mm/yyyy')"
TO="to_date(decode(substr(:${n},2,1),' ',null,:${n}),'dd/mm/rrrr')"

Hi
I done have a problem with variable substitution
the problem is I need to change variable lines in one file and write out the fixed file
currently it loops through the file and changes the lines one by one and each replacement over writes the previous one. So in the end only the last line is converted.

Hi I seem to have a solution any better ideas ?
set -vx
CTL=`grep to_date *.ctl | grep decode | cut -f1 -d':'`
echo $CTL
for i in $CTL
do
COL=`grep to_date $i | grep decode | awk '{print $1}' | cut -f1 -d":"`
echo $COL
for n in $COL
do
FROM="decode(substr(:$n,2,1),' ',null,to_date(:"$n", 'dd/mm/yyyy')"
TO="to_date(decode(substr(:$n,2,1),' ',null,:$n),'dd/mm/rrrr')"
echo 's!'"$FROM"'!'"$TO"'!' >> change.sed
done
sed -f change.sed $i > $i.out
>change.sed
done