Error
Error Code:
693
SAP S/4HANA Error 693: Corrupt SQL Plan Table
Description
This error signifies an issue with SAP S/4HANA's SQL plan stability feature, indicating that the stored plan table, crucial for optimizing database queries, is corrupt. It typically occurs when the system attempts to load or utilize these pre-optimized execution plans, potentially leading to query failures or degraded performance.
Error Message
ERR_SQL_PLAN_STABILITY_MAP_LOAD_ERROR_DEPRECATED
Known Causes
4 known causesDatabase File Corruption
Underlying database issues, such as hardware failures, power outages, or storage system malfunctions, can lead to the corruption of critical database tables, including those storing SQL execution plans.
Abrupt System Shutdown
An unexpected or forceful shutdown of the SAP S/4HANA system or its underlying database can leave database files in an inconsistent state, potentially corrupting stored SQL plan data.
Software Inconsistencies
Rarely, bugs in SAP S/4HANA or database software, or issues during system updates or patches, can introduce inconsistencies that corrupt plan stability data.
Storage System Issues
Problems with the physical storage infrastructure, such as bad disk sectors or I/O errors, can cause data corruption when the system attempts to write or read SQL plan information.
Solutions
4 solutions available1. Rebuild the SQL Plan Cache easy
This solution clears and rebuilds the corrupted SQL plan cache, often resolving the error with minimal downtime.
1
Access the SAP HANA Studio or SAP HANA Cockpit.
2
Navigate to the SQL Console.
3
Execute the following SQL command to clear the SQL plan cache.
ALTER SYSTEM CLEAR SQL PLAN CACHE;4
Restart the SAP HANA database. This step is crucial for the cache to be rebuilt.
5
Monitor the system after the restart to ensure the error is resolved and application performance is stable.
2. Update SAP HANA Database Statistics medium
Stale or corrupt statistics can lead to incorrect SQL plan generation. Updating them can resolve the issue.
1
Access the SAP HANA Studio or SAP HANA Cockpit.
2
Navigate to the SQL Console.
3
Execute the following command to update statistics for all tables. This can be a resource-intensive operation, so schedule it during a maintenance window.
CALL RECALCULATE_STATISTICS(null, null, 'ALL', 'ALL');4
Alternatively, if you suspect specific tables are causing the issue, you can update statistics for individual tables using:
CALL RECALCULATE_STATISTICS(null, '<schema_name>', '<table_name>', 'ALL');5
Monitor the system for performance improvements and check if the error persists.
3. Investigate and Re-optimize Problematic SQL Statements advanced
This is a more in-depth approach focusing on identifying and fixing the root cause: a specific SQL statement with a corrupt plan.
1
Identify SQL statements that are frequently executed or are known to be slow. Use SAP HANA monitoring tools like the 'SQL Plan Cache' or 'Expensive Statements' view in SAP HANA Cockpit/Studio.
2
For the identified SQL statement, retrieve its current plan using:
SELECT * FROM SYS.PLAN_CACHE WHERE STATEMENT_HASH = <statement_hash>;3
Analyze the retrieved plan for anomalies or indicators of corruption. This might require expertise in SQL query optimization.
4
If a specific statement is identified as the culprit, try to re-optimize it. This could involve:
5
a. Rewriting the SQL query for better efficiency.
6
b. Ensuring appropriate indexes are present and used.
7
c. Using hints to guide the optimizer if necessary (use with caution).
8
After re-optimizing, clear the SQL plan cache (Solution 1) and monitor the system.
4. Apply SAP HANA Database Patches or Updates advanced
SAP often releases patches that address known bugs, including those related to SQL plan management. This is a robust, long-term solution.
1
Consult the SAP Notes for SAP S/4HANA and SAP HANA database to identify any relevant patches or updates that address error code 693 or similar SQL plan issues.
2
Plan for a maintenance window to apply the recommended SAP HANA database patches or updates. This typically involves using SAP's Software Update Manager (SUM) or other relevant tools.
3
Follow the vendor's instructions meticulously for applying the patches/updates.
4
After the update, perform thorough testing of critical business processes and monitor system stability and performance.