Dear all, this is my first post. I have over 20 years Oracle experience and very recently DB2.
Oracle offers the highest level of read consistency, i.e. readers don't block writers and readers do not see uncommitted data (aka dirty reads).
So if I were to do this in Oracle:
CREATE TABLE emp(empno NUMBER, deptno NUMBER, sal NUMBER);
INSERT INTO emp VALUES (1, 10, 1000);
INSERT INTO emp VALUES (2, 10, 1000);
--Now I do not commit and start a new session:
SELECT SUM(sal) FROM emp WHERE deptno=10;
Can I achieve the same results in Teradata? Do readers block writers (or vice versa) and if and when it doesn't, will I see dirty data?
I would be grateful if somebody could try this and confirm.