Add note for Put/Delete operation in the API guide
@@ -546,6 +546,7 @@ Note that you can't specify clustering key boundaries and orderings in Scan with
`Put` is an operation to put a record specified by a primary key.
It behaves as an upsert operation for a record, i.e., updating the record if the record exists; otherwise, inserting the record.
+Note that when you update an existing record, you need to read it using a `Get` or a `Scan` before a `Put` operation.
You need to create a Put object first, and then you can execute it with the `transaction.put()` method as follows:
@@ -585,6 +586,7 @@ Put put =
#### Delete operation
`Delete` is an operation to delete a record specified by a primary key.
+Note that when you delete a record, you need to read it using a `Get` or a `Scan` before a `Delete` operation.
You need to create a Delete object first, and then you can execute it with the `transaction.delete()` method as follows:
