Query to Check for Errors in the Alert Log

SELECT
TO_CHAR(originating_timestamp, 'YYYY-MM-DD HH24:MI:SS') AS error_time,
message_text
FROM
v$diag_alert_ext
WHERE
message_text LIKE '%ORA-%'
AND originating_timestamp >= SYSDATE - 1/24 -- last 1 hour
ORDER BY
originating_timestamp DESC;

SELECT
TO_CHAR(originating_timestamp, 'YYYY-MM-DD HH24:MI:SS') AS error_time,
message_text
FROM
v$diag_alert_ext
WHERE
message_text LIKE '%ORA-%'
AND message_text NOT LIKE 'ORA-0%' -- Exclude ORA-0 errors
AND message_text NOT LIKE '%ORA-01013%' -- Exclude user cancelled operation
AND originating_timestamp >= SYSDATE - 1/24 -- last 1 hour
ORDER BY
originating_timestamp DESC;