Error
Error Code:
608
SAP S/4HANA Error 608: Prepared Statement Limit Exceeded
Description
This error indicates that an application or process interacting with SAP S/4HANA has attempted to create more database prepared statements than the configured limit allows. It typically occurs during periods of high transaction volume or when applications fail to properly close database resources, leading to operational disruption.
Error Message
ERR_API_EXCEED_MAX_PREPARED_STATEMENT
Known Causes
4 known causesHigh Concurrency Workload
Many concurrent users or automated processes are simultaneously executing queries that require prepared statements, quickly consuming available resources.
Application Resource Leak
An application connected to SAP S/4HANA is not properly closing database connections or prepared statements after use, leading to resource exhaustion.
Insufficient Database Configuration
The underlying database or SAP S/4HANA system parameters for prepared statements are set too low for the current operational workload.
Inefficient API Usage
Application code might be repeatedly preparing the same SQL statements unnecessarily instead of reusing existing prepared statements, leading to excessive resource consumption.
Solutions
3 solutions available1. Identify and Optimize High-Frequency Prepared Statements advanced
Analyze the system to find applications generating too many prepared statements and optimize their code.
1
Connect to the SAP HANA database using a SQL client (e.g., SAP HANA Studio, hdbsql).
2
Query the `M_PREPARED_STATEMENTS` system view to identify statements with a high execution count and a low re-use rate. Look for statements that are frequently prepared but not reused efficiently.
SELECT STATEMENT_STRING, EXECUTION_COUNT, PREPARATION_COUNT, REUSE_COUNT FROM M_PREPARED_STATEMENTS ORDER BY PREPARATION_COUNT DESC LIMIT 100;3
Analyze the `STATEMENT_STRING` of the top offenders. Determine which applications or processes are responsible for generating these statements.
4
Work with the application development team to optimize the application code. This might involve:
- Re-using prepared statements instead of preparing them repeatedly.
- Using dynamic SQL cautiously and ensuring proper parameter binding.
- Reviewing SQL logic for unnecessary complexity or redundant operations.
- Re-using prepared statements instead of preparing them repeatedly.
- Using dynamic SQL cautiously and ensuring proper parameter binding.
- Reviewing SQL logic for unnecessary complexity or redundant operations.
5
After code optimization, monitor the `M_PREPARED_STATEMENTS` view again to confirm the reduction in preparation counts.
2. Increase the Prepared Statement Limit (Temporary Measure) medium
Temporarily increase the `prepared_statement_limit` parameter to alleviate immediate pressure.
1
Log in to the SAP HANA system as a user with administrative privileges.
2
Access the SAP HANA cockpit or use `hdbsql` to modify system parameters.
3
Navigate to the system configuration or parameter settings. Locate the `prepared_statement_limit` parameter.
4
Increase the value of `prepared_statement_limit`. The default is typically 100000. Increase it incrementally, for example, to 150000 or 200000, and monitor performance. Avoid excessively large values as they can consume significant memory.
ALTER SYSTEM ALTER CONFIGURATION ('indexserver.ini', 'SYSTEM') SET ('prepared_statements', 'limit') = '150000' WITH RECONFIGURE;5
Apply the changes. This might require a restart of the SAP HANA index server or the entire SAP HANA system, depending on the SAP HANA version and configuration. Consult SAP Notes for specific guidance.
6
Monitor the system closely after the change. If the error persists, further investigation into the root cause is required.
3. Implement Statement Caching Strategies advanced
Configure statement caching to reduce the need for frequent statement preparation.
1
Understand that SAP HANA automatically caches prepared statements. The `prepared_statement_limit` controls the maximum number of statements that can be cached.
2
Ensure that your applications are designed to leverage statement caching. This means preparing a statement once and then executing it multiple times with different parameters.
3
Review application code for instances where statements are prepared within loops or in frequently called functions without proper reuse.
4
Consider using connection pooling in your application. Connection pooling can help in reusing database connections, which in turn can help in reusing prepared statements associated with those connections.
5
If you are using a custom application or a third-party tool, check its configuration for any statement caching or preparation settings that can be optimized.