2000003 – FAQ: SAP HANA

2000003 – FAQ: SAP HANA

Symptom

You are looking for general advice about SAP HANA.

Environment

SAP HANA

Cause




1. Where do I find central information about SAP HANA?
2. How can I determine SAP HANA topology details?
3. What do SAP HANA error codes mean?
4. What has to be considered for BW on SAP HANA?
5. What has to be considered for Suite on HANA?
6. How can the configuration and performance of the SAP HANA hardware, firmware and operating system be checked?
7. What has to be considered when opening an SAP incident?
8. What are the requirements for SAP support service deliveries in SAP HANA environments?
9. What has to be considered for sizing SAP HANA?
10. How can I check the technical consistency of the SAP HANA database?
11. Where can I find information about backup, restore and recovery of SAP HANA?
12. Which trace options exist in the SAP HANA environment?
13. Which limitations exist for the SAP HANA database?
14. What are rule of thumbs for the performance and throughput of SAP HANA operations?
15. Is it possible to run multiple SAP applications on a single SAP HANA appliance?
16. Which clients are supported for SAP HANA?
17. Which timeouts exist on SAP HANA side?
18. What kind of Auto Commit options exist for SAP HANA?
19. Where do I find logs and traces of SAP HANA?
20. How can logs and traces of SAP HANA be purged?
21. What are typical differences between SAP HANA and Oracle?
22. What has to be considered for SAP HANA sidecar scenarios?
23. Can a SAP HANA database be renamed?
24. Can a SAP HANA schema be renamed?
25. Where do I find more information related to SAP HANA extended storage?
26. Where can I find information related to SAP HANA Live?
27. Is it possible to configure an e-mail notification in case of critical SAP HANA states?
28. Is there a standard recommendation for setting SAP HANA parameters?
29. Does SAP HANA support timezones?
30. What has to be considered in terms of the daylight saving time and leap seconds?
31. Where can fragmentation occur in SAP HANA environments?
32. Which administration and monitoring tools exist in SAP HANA environments?
33. What has to be considered when using liveCache in SAP HANA environments?
34. Where can I find an overview of SAP HANA features introduced with certain patch levels?
35. Where can I find information about available, used and deprecated features?
36. Does SAP HANA provide a history of DDL operations?
37. What is the difference between the SAP HANA enterprise edition and the SAP HANA platform edition?
38. Are there any special SAP HANA options that can be purchased on top of the standard SAP HANA edition?
39. Where can I find central information about SAP HANA host and service startups and shutdowns?
40. How can a critical SAP HANA session be terminated?
41. Which types of dumps can be created in SAP HANA environments?
42. How can standalone databases or individual tables be migrated to SAP HANA?
43. How can system copies be performed in SAP HANA environments?
44. How are fetch sizes defined in SAP HANA environments?
45. What can be reasons for unexpected or wrong results of SAP HANA database requests?
46. What kind of temporary and non-persisted tables can be created with SAP HANA?
47. How can the content of this and other SAP Notes with broad tables be displayed properly?
48. How can a SAP HANA connection for SAP support be established?
49. How can I provide input about useful SAP HANA features?
50. How can the historic growth of the SAP HANA database be determined?

Resolution

1. Where do I find central information about SAP HANA?

SAP Notes 1514967 and 1523337 contain central information and important links for SAP HANA.

Documentation for SAP HANA is available at http://service.sap.com/hana and  http://help.sap.com/hana. Particularly important for the technical SAP HANA administration is the SAP HANA Administration Guide.

SAP Note 2402628 describes how to find SAP HANA documentation for earlier Revisions.

SAP HANA software can be downloaded via the SAP Software Download Center (SWDC).

Useful troubleshooting information can be found in the SAP HANA Troubleshooting and Performance Analysis Guide.

At SAP Press the book SAP HANA Administration is published, that provides a detailed overview about SAP HANA architecture and administration tasks with some complementary information to the SAP HANA Administration Guide.

The following FAQ Notes and SCN references for central SAP HANA topics exist:

SAP Note / SCN Link Title   SAP Note / SCN Link  Title 
1642148 FAQ: SAP HANA Database Backup and Recovery 2177604 FAQ: SAP HANA Technical Performance Optimization Service
1999880 FAQ: SAP HANA System Replication 2180119 FAQ: SAP HANA Smart Data Access
1999930 FAQ: SAP HANA I/O Analysis 2180165 FAQ: SAP HANA Expensive Statements Trace
1999997 FAQ: SAP HANA Memory 2185556 FAQ: SAP HANA Cockpit
1999998 FAQ: SAP HANA Lock Analysis 2186744 FAQ: SAP HANA Parameters
2000000 FAQ: SAP HANA Performance Optimization 2200772 FAQ: SAP HANA Statement Routing and Client Distribution Mode
2000002 FAQ: SAP HANA SQL Optimization 2220627 FAQ: SAP HANA LOBs
2000003 FAQ: SAP HANA 2222110 FAQ: SAP HANA Load History
2014562 FAQ: SAP HANA LT Replication Server (SLT) 2222200 FAQ: SAP HANA Network
2039883 FAQ: SAP HANA Database and Storage Snapshots 2222218 FAQ: SAP HANA Database Server Management Console (hdbcons)
2044468 FAQ: SAP HANA Partitioning 2222220 FAQ: SAP HANA DBACOCKPIT
2053330 FAQ: SAP HANA Operations Recommendation for Alerts 2222250 FAQ: SAP HANA Workload Management
2057046 FAQ: SAP HANA Delta Merges 2222277 FAQ: SAP HANA Column Store and Row Store
2057595 FAQ: SAP HANA High Availability 2250144 FAQ: SAP HANA Secure User Store
2073112 FAQ: SAP HANA Studio 2336344 FAQ: SAP HANA Static Result Cache
2081591 FAQ: SAP HANA Table Distribution 2340450 FAQ: SAP HANA Table Replication
2082286 FAQ: SAP HANA Graph 2366291 FAQ: SAP HANA Executed Statements Trace
2100009 FAQ: SAP HANA Savepoints 2380176 FAQ: SAP HANA Database Trace
2100040 FAQ: SAP HANA CPU 2393013 FAQ: SAP HANA Clients
2101244 FAQ: SAP HANA Multitenant Database Containers 2393464 FAQ: SAP HANA Live Content Installation
2112604 FAQ: SAP HANA Compression 2399993 FAQ: SAP HANA Fast Data Access (FDA)
2114710 FAQ: SAP HANA Threads and Thread Samples 2400005 FAQ: SAP HANA Persistence
2115815 FAQ: SAP HANA Database Patches and Upgrades 2400006 FAQ: SAP HANA Statement Hints
2116157 FAQ: SAP HANA Consistency Checks and Corruptions 2400007 FAQ: SAP HANA Runtime Dumps
2124112 FAQ: SAP HANA Parsing 2400022 FAQ: SAP HANA Smart Data Integration (SDI)
2127458 FAQ: SAP HANA Loads and Unloads 2412519 FAQ: SAP HANA SQL Trace Analyzer
2142945 FAQ: SAP HANA Hints 2416490 FAQ: SAP HANA Data Aging in SAP S/4HANA
2143736 FAQ: SAP HANA Table Distribution for BW 2477204 FAQ: SAP HANA Services and Ports
2147247 FAQ: SAP HANA Statistics Server 2502256 FAQ: SAP HANA Caches
2159014 FAQ: SAP HANA Security 2506811 FAQ: SAP HANA Dynamic Result Cache
2160391 FAQ: SAP HANA Indexes
2165547 FAQ: SAP HANA Database Backup & Recovery in a SAP HANA System Replication Landscape DOC-62942 FAQ: SAP HANA Tailored Data Center Integration
2169283 FAQ: SAP HANA Garbage Collection DOC-64640 FAQ: SAP HANA Operations
2177064 FAQ: SAP HANA Service Restarts and Crashes DOC-66702 FAQ: High Availability for SAP HANA

2. How can I determine SAP HANA topology details?

Topology details like involved hosts, services and roles can be determined in different ways:

Tool Details
M_SERVICES This monitoring view contains information about the available SAP HANA services and their roles.

You can use SQL: “HANA_Services_Overview” (SAP Note 1969700) for displaying this information.

M_TOPOLOGY_TREE This monitoring view provides further topology details. It must be started with an equal predicate on the PATH column. You can start with PATH = ‘/’ and then dig deeper level by level (e.g. PATH = ‘/host’, PATH = ‘/host/<host_name>’).
landscapeHostConfiguration.py You can use the script landscapeHostConfiguration.py in the python_support folder in order to display topology information. Unlike the monitoring views, this approach can also be used when SAP HANA is down.

3. What do SAP HANA error codes mean?

SAP HANA server error codes are positive numbers. You can determine further details including a short description via SQL: “HANA_ErrorCodes” (SAP Note 1969700).

If client connections are done using SQLDBC, negative SQLDBC error codes can be thrown. SAP Note 1929772 provides an overview.

4. What has to be considered for BW on SAP HANA?

General information for operating BW on SAP HANA is available in SAP Note 1600929. Sizing SAP HANA for BW is described in SAP Notes 1637145 and 2296290.

SAP Note 1729988 provides checks that can be performed when migrating an existing NetWeaver BW installation to SAP HANA.

SAP HANA scale out scenarios with BW take advantage of special table distribution and partitioning features. SAP Notes 19080752334091 and SCN document http://scn.sap.com/community/hana-in-memory/blog/2013/09/03/ contain more detailed information.

Large tables on BW side can be handled as described in SAP Notes 2019973 and 2374652.

If you want to run BW on a scale-out solution, at least three SAP HANA nodes should be used (SAP Note 1702409).

5. What has to be considered for Suite on HANA?

The minimum requirement for Suite on HANA is NetWeaver release 7.40.

SAP cluster and pool tables are changed to transparent tables on SAP HANA, so compared to other SAP databases you can see some new physical table names on SAP HANA, e.g.:

  • Transparent table KONV instead of cluster table KOCLU
  • Transparent table BSEG instead of cluster table RFBLG
  • Transparent table CDPOS instead of cluster table CDCLS
  • Transparent table EDID4 instead of cluster table EDI40

SAP Note 1950470 describes the hardware prerequisites for Suite on HANA.

SAP Notes 1793345 and 1872170 contain sizing information for Suite on HANA.

SAP pilot Note 1781986 describes the prerequisites for scale-out scenarios on Suite on HANA. Customers interested in piloting SoH scale-out can open a SAP incident with reference to SAP pilot Note 1781986. SAP Note 1899817 describes table distribution in scale-out scenarios.

6. How can the configuration and performance of the SAP HANA hardware, firmware and operating system be checked?

Information about certified and supported hardware in SAP HANA environments can be found in the SAP hardware directory.

For optimal performance you should make sure that the /tmp directory resides on a local file system (see SAP Note 2100296).

SAP Note 1943937 describes a hardware configuration check tool that provides functionality to check if the hardware performance is sufficient for a production SAP HANA installation.

See SAP Note 1922310 related to firmware changes in SAP HANA environments.

The following SAP Notes provide information related to specific OS or hardware products:

SAP Note Product Area
2235581 OS SAP HANA: Supported Operating Systems
1944799 SLES SAP HANA Guidelines for SLES Operating System Installation
1944415 SLES Configuration Guide for Hardware Platforms of SuSE Linux Enterprise Server
1650046 Lenovo Lenovo Solution for SAP HANA – Operations Guide
1661146 Lenovo Lenovo/IBM Check Tool for SAP HANA appliances
1880960 Lenovo Lenovo Systems Solution for SAP HANA Platform Edition FW/OS/Driver Maintenance
1930395 Lenovo HANA Server Disk Quota Administration
2100566 Lenovo Frequently Asked Questions for Lenovo/IBM saphana support script
2055470 IBM HANA on POWER Planning and Installation Specifics – Central Note
2133369 IBM SAP HANA on IBM Power Systems: Central Release Note
2161991 VMware VMware vSphere configuration guidelines
2015392 VMware VMware recommendations for latency-sensitive SAP applications

7. What has to be considered when opening an SAP incident?

SAP Note 1976729 contains an overview of application components that can be used for SAP HANA incidents.

SAP Note 1758890 lists the information that is required by SAP support to analyze the problem efficiently.

See SAP Note 1747042 and make sure that a database user with sufficient privileges is provided in case the SAP support needs to connect to the database directly.

SAP support may require a data export in order to reproduce a problem. SAP Note 1785797 describes how to perform an export.

8. What are the requirements for SAP support service deliveries in SAP HANA environments?

SAP Note 1892593 describes the necessary preparations that are required for a successful SAP support service delivery in SAP HANA environments.

9. What has to be considered for sizing SAP HANA?

Detailed sizing information for different environments can be found in the following SAP Notes:

Sizing Area SAP Note
General information 1514966
BW 1637145
1736976
BW 3.5: 2021372
2296290
Suite on HANA,
S/4HANA
1793345
1872170
Dynamic tiering 2086829
Smart data streaming 2184297
Remote data sync 2210231

10. How can I check the technical consistency of the SAP HANA database?

SAP Note 1977584 provides an overview of tools that can be used to verify the technical consisteny of the SAP HANA database and of related areas like backups.

11. Where can I find information about backup, restore and recovery of SAP HANA?

See SAP Note 1642148 for popular questions and answers in the area of backup, restore and recovery of SAP HANA. SAP Note 2091951 provides a best practice document for backups, restore and recovery.

SAP Note 2031547 lists the available 3rd party software products for backup operations (backint).

SAP Note 2039883 answers questions around storage snapshots in SAP HANA environments.

12. Which trace options exist in the SAP HANA environment?

SAP HANA provides many trace options for various purposes. Several of them can be found in the “Administration” –> “Trace Configuration” section of SAP HANA Studio.

See SAP Note 2119087 for more information.

13. Which limitations exist for the SAP HANA database?

See SAP Note 2154870 for limitations in the SAP HANA environment.

14. What are rule of thumbs for the performance and throughput of SAP HANA operations?

The following table lists some typical performance values for SAP HANA operations. The actual performance depends on many factors including parallelism, available resources and I/O speed, so the values are only rough indications for well-configured constellations and can’t be taken for granted.

Activity Duration / Throughput Details
R3load export 100 – 500 GB / h Export from source database (different from SAP HANA)
R3load import 100 – 1000 GB / h Import into SAP HANA database (throughput based on source database size)
Row store load 10 GB / min Throughput of loading row store information into memory during SAP HANA startup
Quick selection (row store) 0.02 ms Time an optimal selection from a SAP HANA row store table takes (server side)

Measured values on client side much higher due to network / communication overhead

Quick selection (column store) 0.05 ms Time an optimal selection from a SAP HANA column store table takes (server side)

Measured values on client side much higher due to network / communication overhead

Data backup 100 – 1000 GB / h Backup of data to disk
Data recovery (restore) 100 – 1000 GB / h Restore of a data backup
Log recovery 80 – 800 GB / h Recovery of logs
Column store startup after log recovery 100 – 1000 GB / h A log recovery builds up potentially large delta storages (SPS <= 09). They are merged table by table when SAP HANA starts up next time. The column store startup time after a log recovery depends on the amount of recovered data which influences the sizes of the delta storages.

15. Is it possible to run multiple SAP applications on a single SAP HANA appliance?

See SAP Note 1681092 that describes under what circumstances you can implement multiple SAP HANA databases on a single SAP HANA appliance.

See SAP Notes 1661202 and 1826100 that describe under what circumstances you can implement multiple SAP applications in a single SAP HANA database. This scenario is also called MCOD (“multiple components in one database”).

SAP Note 1953429 describes in which situations it is possible to run SAP HANA and a SAP NetWeaver application server ABAP on one host.

SAP Note 2024433 describes the prerequisites to run more than one SAP HANA virtual machine (VM) on one host.

SAP Note 2248291 describes details for running multiple applications on the same machine of a S/4HANA on-premise system.

Further information on SAP landscape recommendations can be found in the SAP HANA System Landscape Guide (http://www.saphana.com/docs/DOC-4385) and at http://wiki.scn.sap.com/wiki/display/SLGB/Landscape+Recommendations.

16. Which clients are supported for SAP HANA?

SAP Note 1577128 provides information related to clients supported in SAP HANA environments.

17. Which timeouts exist on SAP HANA side?

The most important timeouts on SAP HANA side are:

Parameter Default Unit SAP Note Description  Error message
daemon.ini -> [daemon] -> forcedterminationtimeout
15000 (15 seconds) ms 2177064 Hard shutdown duration before processes are terminated with SIGKILL

daemon.ini -> [daemon] -> terminationtimeout
300000 (5 minutes) ms 2177064 Soft shutdown duration before processes are terminated with SIGKILL

global.ini -> [backup] -> backint_response_timeout
600 (10 minutes) s 2333129 Time after which a BACKINT request is terminated.
BackupDestBackint_Executor: Backint did not respond for <seconds> seconds, killing pid <pid>
global.ini -> [backup] -> data_backup_savepoint_lock_timeout
7200 (2 hours) s 2100009 Time after which a backup is terminated when its savepoint is not finished successfully
global.ini -> [persistence] -> log_backup_timeout_s
900 (15 minutes) s 1642148 Time after which a log backup is performed at latest
global.ini -> [system_replication] -> logshipping_timeout
30 s 1999880 Time after which a synchronous replication of a log buffer is terminated
sr_dataaccess DisasterRecoveryPrimaryImpl.cpp(00369) : Closing connection to siteID 2. 
LogShipping was waiting for 36 seconds (logshipping_timeout = 30)!"
indexserver.ini -> [communication] -> default_read_timeout
-1 (no timeout) ms 2222200 Time after which a read request is terminated; internally certain operations may use specific hard-coded timeouts (e.g. 10 s, 60 s) that can’t be adjusted.
a timeout occured while reading from the channel





active channel from ... to ...: reading failed with timeout error; timeout=<timeout>ms elapsed
indexserver.ini -> [communication] -> signal_recv_timeout
5000 ms 2427296 Time after which a receive request to the own listen port is terminated
caught network exception BadParam//channel not in list! while mapping from handle to channel in main loop
indexserver.ini -> [communication] -> signal_send_timeout
5000 ms 2427296 Time after which a send request to the own listen port is terminated
caught network exception BadParam//channel not in list! while mapping from handle to channel in main loop
indexserver.ini -> [row_engine] -> startup_consistency_check_timeout
600 s 2116157 Timeout of row store consistency check during startup (SAP HANA >= 2.00.010)

indexserver.ini -> [session] -> initial_receive_timeout
5000 ms 2385992 Time after which a connection request is terminated
cannot establish session because the initial communication timeout was reached: timeout=<timeout_ms>
indexserver.ini -> [transaction] -> lock_wait_timeout
1800000 (30 minutes) ms 1999998 Time after which a record or table lock wait is terminated
SQL error 131: transaction rolled back by lock wait timeout
indexserver.ini -> [session] -> idle_connection_timeout
1440 (1 day) min 1836774 Time after which an idle connection is terminated
(idle connection) Close long lived idle connection (conn_id:<conn_id>, part:<num>, sockfd:<num>, 
last_action:ExecuteStatement): threshold=1440, idle time=1440 (minutes)

This warning message is only visible if the database trace level for component sqlsession is set to at least WARNING.

If an update transaction exists for the terminated connection, the client process is terminated (when it accesses the database the next time) with an error in order to avoid inconsistencies, e.g.:

SQL error "SQL code: -10807" occurred while accessing table
System call 'send' failed, rc=10054:An existing connection was forcibly closed 
by the remote host.
System call 'send' failed, rc=104:Connection reset by peer
indexserver.ini -> [session] -> idle_connection_timeout_application_<app_name>
-1 (idle_connection_timeout) min 2036111 Time after which an idle connection of a specific application is terminated Works like idle_connection_timeout above, but is restricted to the defined application (e.g. ‘statisticsserver’, or ‘hdbstudio’)
indexserver.ini -> [session] -> tcp_keepalive_time
600 (10 minutes) s 1836774 Time after which a dead connection is terminated
xsengine.ini -> [httpserver] -> max_request_runtime
300 (5 minutes) s 2159899 Maximum runtime of xsengine requests
xsengine.ini -> [httpserver] -> sessiontimeout
900 (15 minutes) s 2159899 Time after which an xsengine session is terminated

Furthermore the following timeout can be configured as SAP ABAP profile parameter:

Parameter Default Unit Description
dbs/hdb/connect_property = CONNECTTIMEOUT=<ms> Primary connection: 0 (no timeout)

Service connection, DBSL >= 7.42 (23): 0 (no timeout)
Service connection, DBSL <= 7.42 (22): 30000

Secondary connections: 30000

ms Time after which a client connection request to SAP HANA is terminated (error -10709, “Connect failed (connect timeout expired)”)

CONNECTTIMEOUT settings for secondary connections can be set as described in SAP Note 1983389.

18. What kind of Auto Commit options exist for SAP HANA?

SAP HANA provides the following Auto Commit options:

Auto Commit Type Description
Auto Commit after each DML statement SAP HANA Studio -> SQL Editor -> Properties -> Sessions -> Auto Commit

On:  COMMIT is issued after each executed SQL statement (default)
Off: Manual execution of COMMIT is required

HDBSQL interactive option: \a

\a ON:  COMMIT is issued after each executed SQL statement (default)
\a OFF: Manual execution of COMMIT is required

HDBSQL command line option: -z

-z: Manual execution of COMMIT is required

Auto Commit after each batch of rows during a DML statement SQL command: ALTER TABLE … COLUMN BATCH <size> 
SQL command: IMPORT .. BATCH <size>BATCH <size>: COMMIT is issued after <size> records are processed
Auto Commit after each DDL statement SQL command: SET TRANSACTION AUTOCOMMIT DDL [ ON | OFF ]

ON:  COMMIT is issued after each DDL operation (default)
OFF: Manual execution of COMMIT is required

In addition some undocumented parameters exist that can control the COMMIT frequency of DML operations in the row store by defining batch sizes:

  • indexserver.ini -> [transaction] -> parallel_batch_insert_threshold
  • indexserver.ini -> [row_engine] -> bulk_delete_threshold

It is not recommended to touch these parameters unless explicitly requested by SAP.

19. Where do I find logs and traces of SAP HANA?

The log and trace files are written to directory /usr/sap/<HANA_SID>/HDB<inst_number>/<host>/trace.

Example:

/usr/sap/C11/HDB00/saphana01/trace

20. How can logs and traces of SAP HANA be purged?

The parameters maxfiles (default: 10 files) and maxfilesize (default: 10 MB) in the [trace] section of global.ini or a specific service control the trace file rotation. SAP HANA writes the files on a rotation basis and switches to the next file whenever the current file reached the maxfilesize limit.

The parameter global.ini –> [trace] –> maxalertfilesize defines the maximum size of alert files (default: 50 MB). When the configured size is reached, the file is compressed (including a timestamp in its name) and a new file is written from scratch.

Avoid increasing these settings unless there is a specific need. Otherwise more and / or larger files are kept for a longer time.

In ABAP stack environments you can delete files via transaction DBACOCKPIT:

DBACOCKPT -> Diagnostics -> Diagnosis Files -> Delete File(s)

On operating system level you can manually delete files if required.

From SAP HANA side you can purge SAP HANA logs and traces using the following commands:

Command Details
ALTER SYSTEM REMOVE TRACES ('<host>', '<file1>' [, '<file2>', ...])
Deletes the individually specified trace files (unless they are currently opened by the related process)
ALTER SYSTEM CLEAR TRACES <trace_type> [UNTIL <date>] [WITH BACKUP]
Deletes all trace files belonging to the specified trace type (e.g. ‘ALERT’ -> alert traces)

If “UNTIL <date>” is added (available with SAP HANA >= 1.00 SPS 12), traces up to the defined point in time are cleared.

If WITH BACKUP is added, the traces are compressed and saved instead of removed.

SQL: “HANA_TraceFiles_Overview” (SAP Note 1969700) can be used to show files exceeding a defined retention time and generate the related cleanup commands.

21. What are typical differences between SAP HANA and Oracle?

SAP Note 1969815 describes some differences in the SQL area between SAP HANA and Oracle.

The following table contains typical differences in technical aspects between SAP HANA and Oracle:

Area Details
Amount of generated (redo) logs Typically 50 % to 100 % of the Oracle redo log generation is observed on SAP HANA side.

22. What has to be considered for SAP HANA sidecar scenarios?

SAP HANA can be used for specific functionalities in parallel to a classic SAP database. This scenario is called sidecar or side-by-side. SAP Note 1694697 provides further details.

23. Can a SAP HANA database be renamed?

You can use the SAP HANA tool hdbrename in order to change the SAP HANA database name or the involved host names.

24. Can a SAP HANA schema be renamed?

No, it is not possible to modify the name of a SAP HANA schema. You have to recreate a new schema from scratch and can e.g. use the EXPORT / IMPORT approach described in SAP Note 2362492 in order to regenerate the data in the new schema name.

25. Where do I find more information related to SAP HANA extended storage?

Extended storage typically contains “warm” data that is accessed from time to time. So there is neither a need to treat it as “hot” data (processed in SAP HANA memory) nor as “cold” data (located on near-line storage). Instead it is a layer in between.

See SAP Note 1983178 and the documents attached to it for further information of using extended storage in BW environments.

26. Where can I find information related to SAP HANA Live?

SAP HANA Live allows real-time operational reporting. See http://www.saphana.com/docs/DOC-2923 and SAP Note 1778607 for further details.

27. Is it possible to configure an e-mail notification in case of critical SAP HANA states?

It is possible to configure e-mail notifications for SAP HANA alerts. See the related information in the SAP HANA administration guide (http://help.sap.com/hana/SAP_HANA_Administration_Guide_en.pdf) for more information. If you require a quick notification in case of certain problems you should check if an alert can be used to identify these problem situations. If that is not possible, you have to use other tools (e.g. SAP Solution Manager, third party monitoring tools) for setting up notifications.

For the future it is planned to set up individual alerts with SAP HANA which can then be used as basis for e-mail notifications.

28. Is there a standard recommendation for setting SAP HANA parameters?

In most cases the default SAP HANA parameters are working fine, but for some reasons (e.g. workaround for bugs, individual optimizations or administrative settings) it is useful to adjust parameters based on the needs. SQL: “HANA_Configuration_Parameters” (SAP Note 1969700) can be used to check for parameters which might have to be adjusted. See SAP Note 2186744 for more information regarding SAP HANA parameter settings.

29. Does SAP HANA support timezones?

Yes, see SAP Note 1791342 for more details.

30. What has to be considered in terms of the daylight saving time and leap seconds?

The document Preparing Your SAP Environment for Daylight Savings Time provides an overview of DST related recommendations in SAP environments including a reference to important SAP HANA Notes.

Leap seconds are small time adjustments which can have critical impact like high load on Linux boxes. See SAP Note 1738172 for more information.

Manual larger adjustments of the SAP HANA server time can have critical consequences in a few scenarios:

  • Logon no longer possible if time is changed to before the start of the SAP HANA license validity (SAP Note 2488990)

31. Where can fragmentation occur in SAP HANA environments?

Fragmentation in this context means space, which is allocated, but not used. In SAP HANA environments it can happen in the following areas:

Area Level  Details SAP Notes
Heap memory Memory Heap memory can fragment to a certain extent, see SAP Note 1999997 (“Can there be fragmentation in the heap memory?”) for more details. 1999997
Row store Memory The row store can fragment over time. It is possible to reorganize the row store in order to eliminate this space overhead.

As of SAP HANA SPS 09 single row store tables can be reorganized via:

ALTER TABLE "<table_name>" RECLAIM DATA SPACE
1813245
Data volumes Disk The disk volumes with the table data can be much larger than the actually used space. This increases the disk space utilization, imposes the risk of filesystem overflows and results in increased backup sizes for file-based backup approaches. The standard SAP HANA backup generally only saves the used space, so it is not impacted. It can be defragmented using the ALTER SYSTEM RECLAIM DATAVOLUME command. 1870858
LOB files Disk LOB files are allocated with fix sizes and depending on the actual value length there can be wasted space. For example, the minimum LOB page size is 4 KB. If the average LOB value is only 2 KB, the allocated space (M_TABLE_LOB_FILES.PHYSICAL_SIZE) is twice as large as the actual data size (M_TABLE_LOB_FILES.BINARY_SIZE). 2220627

32. Which administration and monitoring tools exist in SAP HANA environments?

The main administration and monitoring tools in SAP HANA environments is SAP HANA Cockpit (SAP Note 2185556). This is the replacement for the earlier administration tool SAP HANA Studio (SAP Note 2073112).

An additional common monitoring option is the DBACOCKPIT transaction in ABAP environments. For all ABAP systems on SAP HANA you can use the local DBACOCKPIT transaction. For non-ABAP systems you can configure a remote DBACOCKPIT connection from an ABAP system, e.g. Solution Manager. See SAP Note 2222220 for more information.

SAP Note 1969700 contains a SQL statement collection for SAP HANA that can be used for analyzing and optimizing the SAP HANA database.

SAP Note 2400024 describes typical administration and monitoring tasks in SAP HANA environments.

33. What has to be considered when using liveCache in SAP HANA environments?

See SAP Notes 20375852074788 and 2074843 related to the patch strategy and the versions of liveCache databases integrated in SAP HANA.

34. Where can I find an overview of SAP HANA features introduced with certain patch levels?

Information about new features can be found in “What’s new” document of the SAP HANA Platform Release Notes.

35. Where can I find information about available, used and deprecated features?

Feature information is available in monitoring views M_FEATURES and M_FEATURE_USAGE. You can use the following SQL statements available via SAP Note 1969700 to display this information:

SQL statement Details
SQL: “HANA_Features” Overview of SAP HANA features available in the system, including their version
SQL: “HANA_Features_Usage” Overview of SAP HANA features available in the system, including their usage and deprecation state

SAP Note 2425002 provides further details for features being deprecated with SAP HANA 2.0.

36. Does SAP HANA provide a history of DDL operations?

Up to SAP HANA SPS 10 it doesn’t record histories of DDL operations. If you want to determine details about executed DDL operations, you have to set up appropriate auditing.

Starting with SAP HANA SPS 11 you can use the executed statements trace for recording DDL statements (SAP Note 2366291).

37. What is the difference between the SAP HANA enterprise edition and the SAP HANA platform edition?

The software for both editions is identical, only the underlying contracts are different. See SAP Note 1817105 for more information.

38. Are there any special SAP HANA options that can be purchased on top of the standard SAP HANA edition?

Several options like Dynamic Tiering or Smart Data Streaming are available on top of the standard SAP HANA edition. See SAP Note 2091815 for more information.

39. Where can I find central information about SAP HANA host and service startups and shutdowns?

The daemon trace file records all activities like service startup and shutdown, and so it can be used to check when SAP HANA or specific services were started and stopped.

40. How can a critical SAP HANA session be terminated?

Long running SAP HANA sessions can become critical due to resource consumption, MVCC issues or locks. See SAP Note 2092196 for more information.

41. Which types of dumps can be created in SAP HANA environments?

The following dump types exist in SAP HANA environments:

Dump type File name pattern SAP Note Description
Crash dump <service>_<host>.<port>.crashdump.<timestamp>.trc 2177064 Automatic dump during a service crash
Emergency dump <service>_<host>.<port>.emergencydump.<timestamp>.trc 2177064 Special kind of crash dump triggered by SAP HANA (e.g. when it exits without a crash due to an unforeseen situation)
Out of memory cleanup dump <service>_<host>.<port>.rtedump.<timestamp>.after_oom_cleanup.trc 1999997 Automatic dump to document the memory state after cleanup of an OOM situation, can be useful to identify memory leaks (i.e. memory areas that can’t be purged successfully)
Statement memory limit dump <service>_<host>.<port>.rtedump.<timestamp>.compositelimit_oom.trc 1999997 Automatic dump in case a SQL statement exceeds the predefined statement memory limit
Out of memory dump <service>_<host>.<port>.rtedump.<timestamp>.oom.trc 1999997 Automatic dump in case of an out of memory (OOM) situation
Out of memory dump caused by OS limitation <service>_<host>.<port>.rtedump.<timestamp>.oom_memory_release.trc 1999997 Automatic dump in case of an out of memory (OOM) situation reported by operating system

This situation should normally not happen, because the SAP HANA allocation limits should be configured in a way that there is always sufficient memory from an OS perspective. In case of misconfigured allocation limits or a high memory consumption by OS or external processes this scenario is possible.

Page dump <service>_<host>.<port>.rtedump.<timestamp>.page.trc 1977242 Automatic dump in case of page inconsistencies
Runtime dump <service>_<host>.<port>.rtedump.<timestamp>.trc 2400007 Manual creation of a runtime dump (SAP Notes 1813020) or of a full system dump (SAP Note 1732157)
Runtime dump during blocked savepoint <service>_<host>.<port>.rtedump.<timestamp>.savepoint_blocked.trc 2100009 Automatic runtime dump in case of blocked savepoint
Runtime dump (in progress) <service>_<host>.<port>.rtedump_tmp.<timestamp>.trc 2400007 Manual creation of a runtime dump (SAP Notes 1813020) or of a full system dump (SAP Note 1732157) currently in progress; at the end the “_tmp” will be removed by renaming the file.
CHECK_TABLE_CONSISTENCY results <service>_<host>.<port>.table_consistency_check.<timestamp>.trc 2116157 Starting with SAP HANA 2.0 SPS 01 the consistency check with CHECK_TABLE_CONSISTENCY

42. How can standalone databases or individual tables be migrated to SAP HANA?

In order to migrate a standalone database to SAP HANA, the following SAP tools are available:

  • SAP HANA LT Replication Server (SLT, see SAP Note 2014562)
  • Sybase Replication Server
  • BOBJ Data Services

The choice of the proper tool depends on aspects like technical requirements, downtime considerations and data cleansing / manipulation.

43. How can system copies be performed in SAP HANA environments?

The SAP HANA Administration Guide describes in chapter “Copying a Database Using Backup and Recovery” how a homogeneous system copy can be performed based on backup and recovery.

SAP Note 1844468 describes the steps required for a homogeneous system copy on SAP HANA using SWPM.

SAP Note 1775293 describes problems and provides tips for system copies and migrations in the SAP HANA context.

Additionally the SAP HANA BW System Copy Guide provides details how to copy BW systems on SAP HANA.

44. How are fetch sizes defined in SAP HANA environments?

If a database request returns a larger amount of data, it is processed in multiple individual fetches. The size of these fetches depends on the scenario. In the following table typical environments are described:

Tool Setting Default  Details
SAP ABAP client dbs/hdb/cmd_buffersize
dbs/hdb/max_array
1048576
100000
The fetch size of SAP ABAP requests is controlled by the two ABAP profile parameters dbs/hdb/cmd_buffersize and dbs/hdb/max_array.

Per default the SAP ABAP client retrieves up to 1048576 byte (1 MB) and up to 100,000 rows per fetch. So the formula for the fetch size is:

#records = MIN ( dbs/hdb/max_array, ( dbs/hdb/cmd_buffersize / <ABAP_record_length> ) )

The same formula also applies to bulk DML operations like INSERTs.

If LOBs are involved in a bulk DML operation, the following rules apply:

  • piece-wise LOB writes: bulk size is 1, so every record is processed individually
  • Otherwise: rather small bulk size, because LOB length is not known and so a conservative estimation needs to be done
SAP HANA Studio -> SQL console Session -> Single Fetch For Result 1024 Per default the SQL console in SAP HANA Studio fetches up to 1024 rows. By setting the property “Single Fetch For Result” to ‘On’ the fetch size can be adjusted to 1 row.
JDBC client Statement.setFetchSize() 32766 The default fetch size is typically 32766 and can be adjusted individually with the Statement.setFetchSize() method of Statement, PreparedStatement, CallableStatement and ResultSet.

45. What can be reasons for unexpected or wrong results of SAP HANA database requests?

See SAP Note 2222121 for an overview of typical reasons for unexpected or wrong results.

46. What kind of temporary and non-persisted tables can be created with SAP HANA?

The following options exist for creating temporary and non-persisted tables on SAP HANA:

Type Visibility (table) Visibility (data) Persisted  Life time (table)  Life time (data)  Used by Command
Global temporary global session metadata permanent session SQL engine when processing stacked SQL statements (columns COL0, COL1, … or COL$0$, COL$1$, …)
CREATE GLOBAL TEMPORARY [COLUMN] TABLE ...
Local temporary session session session session
CREATE LOCAL TEMPORARY [COLUMN] TABLE ...
No logging global global metadata permanent limited (retention, restart) Certain BW functionalities
CREATE ... TABLE ... NO LOGGING [RETENTION <seconds>]
No delta log global global metadata, data permanent inconsistent data in case of crash
ALTER TABLE ... DISABLE DELTA LOG

Be aware that NO LOGGING is not comparable with NOLOGGING options of other relational databases because of the restricted data life time. Instead DISABLE DELTA LOG can be used to disable the creation of log information without impacting the data life time.

47. How can the content of this and other SAP Notes with broad tables be displayed properly?

Converting SAP Notes to PDF using “PDF Version” and printing it, may result in truncated lines in case of broad tables. As a workaround you can convert the document to “Printer-friendly version” and use a PDF program (e.g. defined as printer) on this result.

If the display of the SAP Note is already truncated on the screen, you can copy the SAP Note content in the clipboard (CTRL-A / CTRL-C) and paste it into a Word document as a workaround, then all details should be visible.

48. How can a SAP HANA connection for SAP support be established?

The following SAP Note describes how to set up a SAP HANA Studio support connection:

SAP Note Title Details
1592925 SAP HANA Studio Service Connection This SAP Note describes the required steps to configure a SAP HANA Studio connection. See SAP Note 2073112 for more information about SAP HANA Studio.

49. How can I provide input about useful SAP HANA features?

SAP Note 2265872 describes how you can check if a certain missing SAP HANA feature is already requested and – if not – request it yourself.

50. How can the historic growth of the SAP HANA database be determined?

Historic SAP HANA growth information can be found in client tools like SAP Solution Manager.

From a SAP HANA server perspective the following options exist to determine the historic growth of the SAP HANA database:

Monitoring view Details
HOST_VOLUME_FILES This view is populated by the statistics server (SAP Note 2147247) and stores historic sizes of the SAP HANA volumes (including used vs. allocated space details). You can use SQL: “HANA_Disks_Overview” with FILE_TYPE = ‘DATA’, DATA_SOURCE = ‘HISTORY’, AGGREGATE_BY = ‘TIME’ and TIME_AGGREGATE_BY = ‘DAY’ (SAP Note 1969700) to check for historic sizes:

----------------------------------------------------------------------------------------
|SNAPSHOT_TIME   |FILE_TYPE|TOTAL_SIZE_GB|USED_SIZE_GB|UNUSED_SIZE_GB|FRAGMENTATION_PCT|
----------------------------------------------------------------------------------------
|2017/01/26 (THU)|DATA     |       708.53|      179.85|        528.68|            74.61|
|2017/01/25 (WED)|DATA     |       608.18|      242.44|        365.73|            60.13|
|2017/01/24 (TUE)|DATA     |       467.87|      176.97|        290.89|            62.17|
|2017/01/23 (MON)|DATA     |       467.87|      176.37|        291.50|            62.30|
|2017/01/22 (SUN)|DATA     |       467.87|      173.76|        294.11|            62.86|
----------------------------------------------------------------------------------------
GLOBAL_TABLE_PERSISTENCE_STATISTICS This view is populated by the statistics server (SAP Note 2147247) and stores historic sizes of the SAP HANA tables. It can be used to determine historic database sizes, e.g. using SQL: “HANA_Tables_IOStatistics” with AGGREGATE_BY = ‘TIME’, TIME_AGGREGATE_BY = ‘DAY’ (SAP Note 1969700):

-------------------------------
|SNAPSHOT_TIME   |DISK_SIZE_GB|
-------------------------------
|2016/09/22 (THU)|     3303.18|
|2016/09/21 (WED)|     3299.45|
|2016/09/20 (TUE)|     3294.86|
|2016/09/19 (MON)|     3294.69|
|2016/09/18 (SUN)|     3289.09|
|2016/09/17 (SAT)|     3289.12|
|2016/09/16 (FRI)|     3281.16|
|2016/09/15 (THU)|     3267.02|
-------------------------------

For weekly or monthly operations you can use TIME_AGGREGATE_BY = ‘YYYY/WW’ and ‘YYYY/MM’ instead.

The default retention time is 42 days, but it can be adjusted according to SAP Note 2147247 based on your needs.

Only tables with sizes >= 10 MB are considered for GLOBAL_TABLE_PERSISTENCE_STATISTICS, so the actual database size can be slightly larger than the shown values.

M_BACKUP_CATALOG M_BACKUP_CATALOG contains the backup size that is also a good indicator for the database size. You can e.g. use SQL: “HANA_Backup_BackupRuns” with BACKUP_TYPE = ‘complete data backup’, AGGREGATE_BY = ‘TIME’ (SAP Note 1969700):

------------------------------------
|START_TIME         |BACKUP_SIZE_MB|
------------------------------------
|2016/10/22 23:30:02|    3613600.01|
|2016/10/15 23:30:01|    3575504.01|
|2016/10/08 23:30:01|    3583744.01|
|2016/10/01 23:30:01|    3553808.01|
|2016/09/24 23:30:01|    3540336.01|
|2016/09/17 23:30:01|    3535872.01|
|2016/09/10 23:30:01|    3526624.01|
|2016/09/03 23:30:02|    3495040.01|
|2016/08/27 23:30:01|    3453216.01|
|2016/08/20 23:30:01|    3441024.01|
|2016/08/13 04:49:14|    3429024.01|
|2016/08/11 18:00:01|    3346720.01|
|2016/08/06 23:30:01|    3389040.01|
|2016/07/30 23:30:01|    3375088.01|
------------------------------------

The availability of data in M_BACKUP_CATALOG is related to your catalog cleanup strategy.

Be aware that the growth is calculated based on disk size and not on the – more volatile and less reliable – memory size.

Keywords

SAP HANA overview general information

Product
Product or Product Version
SAP HANA, platform edition all versions
References

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