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
originating_timestamp,
message_text
FROM
v$diag_alert_ext
WHERE
REGEXP_LIKE(message_text, 'ORA-\d{5}') -- Matches all ORA-XXXXX error messages
AND
originating_timestamp >= SYSDATE - (1/24) -- Retrieves messages from the last 1 hour
AND
message_text NOT LIKE 'ORA-0%' -- Excludes only ORA-0 errors (e.g., ORA-00000)
ORDER BY
originating_timestamp DESC;