Describe the problem
I start two transactions.
One of the transaction SELECT operations can get the data, but the DELETE row returns DELETE 0

To Reproduce
What did you do? Describe in your own words.

1. Set up CockroachDB node

3.The reading and writing data of T2 are inconsistent

Expected behavior
An error should be reported while performing the DELETE operation.

Additional data / screenshots
create table t(a int primary key); insert into t values(1),(2),(3);
T1:BEGIN;select * from t where a=1;delete from t where a=1;
T2:BEGIN;select * from t where a=1;delete from t where a=1;select * from t where a=1;

Environment:

• CockroachDB version 20.2
• Server OS: Linux
• Client app cockroach sql