concatenate phone numbers with same customer id

[jhansi]

if the id is same for several records,then the phone numbers will concatenate.
how to do it with transformer or without using transformer

source
id,name,phone
1,abcd,7687656543
1,abcd,9876342123
2,bmp,6545365342
2,bmp,6575434566
3,xyz,9087878765

target
id,name,phone
1,abcd,7687656543,9876342123
2,bmp,6545365342,6575434566
3,xyz,9087878765

thnx in advance

[hanuman5]

the solution above scenario like this
source---->sort---->transformer---->target
sort the data based on id and provide key change column
in transformer take three stage variables
prevkey 0 integer 1
newaccnt 'n' char 1
accnts 'y' varchar 255

map key change to prevkey
if prevkey=1 then 'y' else 'n' to newaccnt
else
accnts:',':in.accnt
then accnts drag to phonenum

[jhansi]

thnx 4 ur reply.
but when i am giving in.accnt in accnts stage variable...
it is showing that 'in.accnts' column is not defined.what is this 'in.'
where to give this else condition

[jwiles]

Use the name of your input link and column. in.accnts and accnts are examples for you to modify.

[jhansi]

i found the solution for this.

seqfile-->sort-->-->transformer-->remove duplicates-->dataset

in sort stage,set create key change column to true.
then u will get the required output