shell - sed positional replacement with regular expression -

shell - sed positional replacement with regular expression -

i have string

select dateadd(dd,-90, max(col_name)) table_123_name

and want output

select max(col_name) -90 table_123_name

i have tried

cat test.txt|sed "s/dateadd(dd,//i g"|sed 's/\(\[select\]\)\([ \s\t]*\)\([0-9-]*\)\(\[,\]\)\([ \s\t]*\)\([a-za-z0-9(_]*[)]*\)/select \6)\3/i g'

but regular look replace not working

you this,

$ echo 'select dateadd(dd,-90, max(col_name)) table_123_name' | sed 's/dateadd(dd,\([^,]*\), *\([^) ]*)\)) *\(.*\)/\2 \1 \l\3/gi' select max(col_name) -90 table_123_name

i modifier @ lastly helps case-insensitive match , \l\3 turns chars nowadays within 3rd capturing grouping lowercase.

shell sed