Relationship between extension table and number field

[bonsai]

I'm creating a record in a child table that extends the parent table.

The same record is created in the parent table as in the child table.
In this case, the sys_id is identical.
I'm implementing a number field in the parent and child tables.
The number field is incremented each time a record is created. (OOTB)

For some reason, the number field in the parent table is now fewer than the child table.
I thought they were the same record because they have the same sys_id, but for some reason they seem to be counted.
Is this a bug?
Is there a way to prevent this?

[Sneha KH]

Hello @bonsai ,
This is not a bug, its OOTB behaviour. ServiceNow has by default like this. So no need to worry.
If you want to prevent this remove number field from child record and keep only auto-number in parent record.

[Aditya_hublikar]

Hello @bonsai ,

If you have different number field on child table which not belongs to parent table then number count of parent table and child table will be different, its not bug . 

If you use same number field which belongs to parent table and inherited then it will show same number count.

If this helps you then mark it as helpful and accept as solution.

Regards,

Aditya

[UmesH77 · Accepted solution]

Hello @bonsai  , 

This is not a bug.

When you create a record in a child table, ServiceNow creates one row in the parent table and one in the child table with the same sys_id.

But auto-numbering works per table, not per record.

So:

• Parent table increases its number
• Child table increases its own number

That’s why the numbers become different.

---

Best practice

Keep the number field only on the parent table and let child tables inherit it
(or disable auto-number on the child table).

Regards, 

Umesh

[Ankur Bawiskar]

@bonsai 

this is OOTB behavior.

Each table maintains it's own number count via Number maintenance

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