HANA

Bring Your Own JAR (BYOJ) Process

The following is the procedure to add your own JAR to the HANA data source:

1. Log in to the IBM® watsonx.data instance.
2. From the navigation menu, go to the Configurations page and click the Driver manager tile.
3. Click Add driver.
4. Upload the HANA JAR and specify the driver version. Currently, only one JAR(ngdbc-2.17.12.jar) is supported for HANA data source.
5. Click Add. Once the driver is successfully added, it undergoes a series of validation. If the validation is successful, it is set to 'inactive' status otherwise it is set to 'failed' status.
6. Click the vertical ellipsis icon to assign or delete the driver.
7. To assign the driver to an engine:
   • Click Assign.
   • Select one or more engines to assign the driver. Once assigned, the driver is set to 'active' status.
8. To unassign a driver from an engine, users must first introduce another driver.
9. Click Save and restart engine.
10. In the Infrastructure manager, hover over the HANA data source and click the Manage associations icon.
11. Select the engine to modify the catalog's association with it. All in-flight queries on the modified engines are stopped.
12. Click Save and restart engine.

You can link the HANA data source to the engine only when a driver is associated to that engine. Only one HANA driver can be associated to an engine at a time.

Vulnerabilities in JAR

As part of the BYOJ process, users can upload the required JAR files. If a vulnerability is identified in a JAR, a grace period is set for the removal and cleanup activities based on the severity of the security vulnerability as shown in the following table:

The grace period is calculated from the date the vulnerability is reported, plus the specified grace period. Multiple warnings are displayed to the users about the grace period in the Driver manager page (for the admin) as well as in other places like in the ‘Catalogs’ section in the ‘Infrastructure manager’ page and in the ‘Catalogs associated’ section in the ‘Data manager page’. For example, if a customer uses the ngdbc-2.17.12.jar and a critical vulnerability is identified on October 1st, a cleanup process begins immediately after October 31st. This process deletes the driver from the bucket and Presto pods, disassociates the catalog from the engine, disassociates the driver in the Driver Manager page, and deletes the entry.

Limitations for SQL statements

• DROP TABLE statement is supported only when enabled in the catalog.
• By default, HANA creates VARCHAR columns with a size of 1. So, if a base table column is defined with just VARCHAR without specifying a size (For example, VARCHAR(size)), then CTAS (Create Table As Select) operations do not work.
• For data source-based catalogs the CREATE SCHEMA, CREATE TABLE, DROP SCHEMA, DROP TABLE, DELETE, DROP VIEW, ALTER TABLE, and ALTER SCHEMA statements are not available in the Data Manager UI.

Limitations for data types

• BLOB and CLOB data types support only CREATE and SELECT statements.
• BINARY data type supports only SELECT statement.
• The data that is shown for the BLOB and BINARY data types from the UI is in Base64 format, while the result from presto-cli is in hexadecimal format.
• When the fields of data type REAL have 6 digits or more in the decimal part with the digits being predominately zero, the values when queried are rounded off. It is observed that the rounding off occurs differently based on the precision of the values. For example, a decimal number 1.654 when rounded to 3-digits after the decimal point are the same. Another example is 10.890009 and 10.89000. It is noticed that 10.89000 is rounded to 10.89, whereas 10.89009 is not rounded off. This is an inherent issue because of the representational limitations of binary floating point formats. This might have a significant impact when querying involves sorting.