INSERT INTO radcheck(id, username, attribute, op, value) VALUES (,,00:23:32:c2:a9:e8,Auth-Type,:=,Accept);

INSERT INTO radcheck(id, username, attribute, op, value) VALUES (,'','00:23:32:c2:a9:e8','Auth-Type',':=','Accept');

#!/bin/bash
ssh ubnt@xxx.xxx.xxx.xxx brmacs >>MACS.txt mv MACS.txt /etc/persistent scp mhalls@xxx.xxx.xxx.xxx:/etc/persistent/MACS.txt MACS.txt
sed -i "1d" MACS.txt
head -c 58 MACS.txt >>shortmacs.txt
tail -c 18 shortmacs.txt >>usermac.txt
sed 's/"//g' usermac.txt >>usermacrdy.txt
sed -i 's/^/INSERT INTO `radcheck`(`id`, `username`, `attribute`, `op`, `value`) VALUES (,'',/' usermacrdy.txt
sed "s/$/','Auth-Type',':=','Accept');/" usermacrdy.txt > sqlquery.txt
sed -i "s/,,/,'','/" sqlquery.txt
rm -f MACS.txt
rm -f shortmacs.txt
rm -f usermac.txt
rm -f usermacrdy.txt

sed -i 's/^/INSERT INTO `radcheck`(`username`, `attribute`, `op`, `value`) VALUES (/' usermacrdy.txt
sed "s/$/','Auth-Type',':=','Accept');/" usermacrdy.txt > sqlquery.txt
sed -i "s/,'','//" sqlquery.txt

$ sed -r 's/,([^ ),]+)/,'''1'''/g; s/,,/,'''',/g' file
INSERT INTO radcheck(id, username, attribute, op, value) VALUES (,'','00:23:32:c2:a9:e8','Auth-Type',':=','Accept');

$ sed -r "s/,([^ ),]+)/,'1'/g; s/,,/,'',/g" file
INSERT INTO radcheck(id, username, attribute, op, value) VALUES (,'','00:23:32:c2:a9:e8','Auth-Type',':=','Accept');

$ cat script.sed
s/,([^ ),]+)/,'1'/g
s/,,/,'',/g
$ sed -rf script.sed file
INSERT INTO radcheck(id, username, attribute, op, value) VALUES (,'','00:23:32:c2:a9:e8','Auth-Type',':=','Accept');

sed -E -e "s/,([^ ),]+)/,'1'/g" -e "s/,,/,'',/g" file

$ cat file3
 INSERT INTO radcheck(username, attribute, op, value) VALUES (00:23:32:c2:a9:e8,'Auth-Type',':=','Accept');

$ sed -r "s/(([[:xdigit:]:]+)/('1'/" file3
 INSERT INTO radcheck(username, attribute, op, value) VALUES ('00:23:32:c2:a9:e8','Auth-Type',':=','Accept');

sed "s/(([^)]*)[^,]*){0,1},([^,)]*)/1,'2'/g
" <<IN
INSERT INTO radcheck(id, username, attribute, op, value) VALUES (,,00:23:32:c2:a9:e8,Auth-Type,:=,Accept);

INSERT INTO radcheck(id, username, attribute, op, value) VALUES (,'','00:23:32:c2:a9:e8','Auth-Type',':=','Accept');

INSERT INTO radcheck(id, username, attribute, op, value) VALUES (,'','00:23:32:c2:a9:e8','Auth-Type',':=','Accept');INSERT INTO radcheck(id, username, attribute, op, value) VALUES (,'','00:23:32:c2:a9:e8','Auth-Type',':=','Accept');INSERT INTO radcheck(id, username, attribute, op, value) VALUES (,'','00:23:32:c2:a9:e8','Auth-Type',':=','Accept');