NDB Transaction Row Lock

[ArunKumar N]

Hi Experts,

I would like to know how NDB API locks rows

1) If I am updating/deleting an row using NdbOperation will it hold a lock on the row or it will hold lock on the Primar Key

2) If I am updating or deleting an row NdbIndexOperation will it hold a lock on the row or it will hold lcok on the Index alone.

I have the schema following schema

Column-1 is PrimayKey
Column-2 is UniqueIndexed

I have tried the following scenario

1) Table has an row with column-1 = "A" column-2 = "1"
2) A Transaction-1 tries to delete a row using NdbIndexOperation i.e. with column-2 = 1, deletes but NOT COMMITS the transaction
3) Another Transaction-2 tries to Insert a row with column-1 = "B" column-2 = "1"

What I noticed is Transaction-2 is blocked until Transaction-1 commits.

So 1) what locks are held by Transaction-1
2) What locks are held by Transaction-2 and what locks it waits for


Can someone shed some light on this.

Thanks,
Arun