I have a structure data with double mapping for storing and fetching details. Here is the code :

struct data {
    uint a;
    uint b;
mapping(address => mapping(bytes11 => data[])) testidmapping;

Used storevalues() function to store and getvalues() to fetch the values

function storevalues(address owner,bytes11 id,uint a,uint b) public{

function getvalues(address owner,bytes11 id) view returns (uint a){
  data storage k = testidmapping[owner][id];
  return (k.a);


Is this the possible way of double mapping for fetching and storing details? But I am getting this error:

BigNumber() is not a number: (id is printing)

Help will be appreciated...

  • 1
    The error that you're describing sounds like an off-chain error (e.g., Javascript), but there is no off-chain code in your question. – goodvibration Sep 25 '18 at 13:31
  • Also, what is data(a,b) in function storevalues? Variables a and b are not defined anywhere! – goodvibration Sep 25 '18 at 13:32
  • Thank You...I just edited the code, passing the a and b values from javascript. Basically I don't know how to fetching the values from double mapping from a structure? – lekshmi Sep 25 '18 at 13:35
  • You did not refer to my first comment though. – goodvibration Sep 25 '18 at 13:51

As you intended to access an attribute of an arraydata[] you shall provide an index. You might also need a length of an array data so that you can write a loop in backend code to retrieve all the a's stored in an array data.

Refer the following function -

function getValuesAtIndex(address owner,bytes11 id,uint dataindex) view returns (uint a){

  return (testidmapping[owner][id][dataindex].a);


function getDataLength(address owner,bytes11 id)view returns(uint){

  return (testidmapping[owner][id].length);    

Hope it helps! Let me know if any further clarification is required.

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