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How many external Id's are allowed on an object?

There can be at the most 3 external ID fields on an object
Hi ,
You can create upto 7 external id fields on an object, This is new update in salesforce summer 14.
I see, I need to update myself with the release notes :)
hai venkatesh will you please check it is 10 0r 7 with latest summer . in research i found it is 7 t0 10 please conform me
Hi Jagadesh,

I dont have any idea about 10 external id,i read summer 14 relase in pdf its mentioned 7 and see this article also,

please share me the link or pdf where its mentioned 10. external id's.

if u have still doubt, create external id field in  your org and test and let me know.
we can create only 7 external i tested .when i am creating 8 th it gives an error like this "Error: External ID and Unique field limit exceeded"

I hope below link will clarify your doubt.


David "w00t!" LiuDavid "w00t!" Liu
Little known fact - you can ask your friendly Salesforce rep for more External IDs and they'll usually give you more for free!
Avinash AkondiAvinash Akondi

The limit is three per object.

We can create upto 7 External ID's on single object. But anyone please give me one scenario where we require all 7 Ext. ID's for upsert. As per my understanding 1 Ext. ID is sufficient for upsert then where we use all 7 ID's.

Thank you in advance.
Sredhar KaruturiSredhar Karuturi
You can designate up to 25 External ID fields per object.
External ID fields must be Custom text, number or email fields.
External ID fields contain record IDs from systems outside Salesforce.
You can use the upsert call to match against External ID fields during import or integration.
External ID fields are indexed, so selective filters on them should run quickly.

Ref Link:
meenal hardyameenal hardya
Could you please advise what will happen if we will make 25 fields as a external Id as well as Unique id. Will it work or through an error?  
External ID – is a custom field that has the “External ID” attributes checked meaning that it contains unique record identifiers outside of Salesforce.
External id is a custom field which you mark as unique to identify the data uniquely while the data is coming from external source

Only fields with data type Auto number, email, Number and text can be marked as external ID
An object can have most 7 external ID fields

Custom fields marked as unique also count against an object’s limit of 7 external id fields. – Unique fields +External ID fields <=7
Once you make field as external ID – When you go to data import wizard select object, update existing record, In match by field, you can also see the field which you make it external ID

Hope this will help u to understand External ID


You can create up to 25 External ids per objects