Merge files of differrent size with one field common in both files using awk

hi,

i am facing a problem in merging two files using awk,
the problem is as stated below,

file1:

A|B|C|D|E|F|G|H|I|1
M|N|O|P|Q|R|S|T|U|2
AA|BB|CC|DD|EE|FF|GG|HH|II|1
....
....
....

file2 :

1|Mn|op|qr

result file
A|B|C|Mn|op|qr|D|E|F|G|H|I|1
M|N|O|P|Q|R|S|T|U|2
AA|BB|CC|Mn|op|qr||DD|EE|FF|GG|HH|II|1

file1 can have more than 10,000 records
file2 can have only 1000 records,

The field's 2,3,4 from second file (file2) should be read and should be inserted into filed's 4,5,6 in first file (file1) where lastfiled of "ile1 == first field of file2"

please give me the solution.......
Thanks

There are plenty of similar threads - please use the 'Search' function.

To be more precisely, search for NR==FNR.

Regards