How is tx_id calculated in NEM? Does it have any meaning?

Technical Discussion
#1

Just playing with the NEM api and after calling account/transfers/incoming I got an array of transactions. Here is an example of one element from this array:

{‘meta’: {‘hash’: {‘data’: ‘71f66563e6b8f31e23ccaad6ac99266cb433b041d495f54ba291354edf3035c4’},
‘height’: 1315970,
‘id’: 1109303,
‘innerHash’: {}},
‘transaction’: {‘amount’: 14202228088,
‘deadline’: 79684064,
‘fee’: 13000000,
‘message’: {‘payload’: ‘37646336313732353037346665323237’, ‘type’: 1},
‘recipient’: ‘NAGJG3QFWYZ37LMI7IQPSGQNYADGSJZGJRD2DIYA’,
‘signature’: ‘0f623423e3b95d3698be3edc605eb791743bdfab098eb21026fd556f73f4d86476dfa6dc25650c731c0fe99f7002953b084b4c26f713567a2b8a899d5532a70c’,
‘signer’: ‘a025abd5dd0f0e9f226c4673be03a5a3d72cb95b8acd39fe4f2f2c2fb2d1b9ec’,
‘timeStamp’: 79683464,
‘type’: 257,
‘version’: 1744830465}}

Now I know that id is the id of the transaction, but when I am looking at this transaction at the NEM explorer it does not show this tx_id.

So I am wondering:

  1. whether tx_id is important
  2. does this have any meaning
  3. how is it calculated
  4. is it the same on each node
#2

Just bumping this old thread.

#3

As mentioned in https://nemproject.github.io/#initiating-transactions

NIS uses the SHA3-256 hash function. To create a hash of a transaction you need to hash the byte array of the transaction. See the section above to learn how to build the byte array from a transaction.

So hash is calculated from transaction properties.

#4

I think you misunderstood my question. I am not asking about transaction hash (71f66563e6b8f31e23ccaad6ac99266cb433b041d495f54ba291354edf3035c4 from my example). I am asking about id. In my example it is ‘id’: 1109303

#5

Ok:) id is dependend on current node db and can be different for couple nodes and same tx hash. So it should never used to identify transaction.
It’s next id from db sequence probably.