merge file on the basis of 2 fields - awk

Question

file1
session=1|w,eventbase=4,operation=1,rule=15
session=1|e,eventbase=5,operation=2,rule=14
session=2|t,eventbase=,operation=1,rule=13
file2
field1,field2,field3,session=1,fieldn,operation=1,fieldn
field1,field2,field3,session=1,fieldn,operation=2,fieldn
field1,field2,field3,session=2,fieldn,operation=2,fieldn
field1,field2,field3,session=2,fieldn,operation=1,fieldn
Output
field1,field2,field3,session=1,fieldn,operation=1,fieldn,eventbase=4,rule=15
field1,field2,field3,session=1,fieldn,operation=2,fieldn,eventbase=5,rule=14
field1,field2,field3,session=2,fieldn,operation=2,fieldn,NOMATCH
field1,field2,field3,session=2,fieldn,operation=1,fieldn,eventbase=,rule=13
I have Tried
BEGIN { FS = OFS = "," }
FNR == NR {
split($1,s,"|")
session=s[1];
a[session,$3] = session","$2","$3","$4;
next
}
{
split($4,x,"|");
nsession=x[1];
if(nsession in a)print $0 a[nsession,$6];
else print $0",NOMATCH";
}
Issue is I am not able to FIND nsession in 2D array a with if(nsession in a)
matching 2 files on the combination basis of session and operation

Answer 1

Thanks.. it helped.. Now I am learning :) Thanks team
BEGIN { FS = OFS = "," }
FNR == NR {
split($1,s,"|")
session=s[1];
a[session,$3] = session","$2","$3","$4;
next
}
{
split($4,x,"|");
nsession=x[1];
key=nsession SUBSEP $6
if(key in a)print $0 a[nsession,$6];
else print $0",NOMATCH";
}

Answer 2

You can try
awk -f merge.awk file1 file2
where merge.awk is
NR==FNR {
sub(/[[:blank:]]*$/,"")
getSessionInfo(1)
ar[ses,op]=",eventbase="evb",rule="rule
next
}
{
sub(/[[:blank:]]*$/,"")
getSessionInfo(0)
if ((ses,op) in ar)
print $0 ar[ses,op]
else
print $0 ",NOMATCH"
}
function getSessionInfo(f, a) {
match($0,/session=([^|])[|,]/,a)
ses=a[1]
match($0,/operation=([^,]),/,a)
op=a[1]
if (f) {
match($0,/eventbase=([^,]),/,a)
evb=a[1]
match($0,/rule=(.*)$/,a)
rule=a[1]
}
}