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CREATE OR REPLACE FUNCTION FCN_SLOW
RETURN NUMBER IS
BEGIN
DBMS_SESSION.SLEEP(5); --5 seconds
RETURN 0;
END FCN_SLOW;
/
SELECT * FROM USER_ERRORS;
SELECT A1 + A1
FROM (SELECT FCN_SLOW () AS A1
FROM DUAL)
| A1+A1 |
|---|
| 0 |
SELECT A1 + A1
FROM (SELECT FCN_SLOW () AS A1
FROM DUAL
WHERE ROWNUM >= 1)
| A1+A1 |
|---|
| 0 |
WITH slow_query(a1) AS (
SELECT /*+ materialize */
FCN_SLOW ()
FROM DUAL
)
SELECT A1 + A1
FROM slow_query
| A1+A1 |
|---|
| 0 |