Cassandra

Cassandra is an open-source NoSQL distributed database that handles a huge amount of data across commodity servers.

watsonx.data on IBM Software Hub

watsonx.data Developer edition

Cassandra

Configure the following details for Cassandra:

Field Description
Display name Enter the database name to be displayed on the screen.
Hostname Enter the Hostname.
Port Enter the Port number.
Username Enter the Username.
Password Enter the Password.
Port is SSL enabled Use the toggle switch to enable or disable SSL connection. If enabled,

i. The Upload SSL certificate (.pem, .crt, .cert, or .cer) link is enabled.

ii. Click the Upload SSL certificate (.pem, .crt, .cert, or .cer) link.

iii. Browse the SSL certificate and upload.
Test connection Click the Test connection link to test the database connection. If the database connection is successful, a success message appears.
Catalog name Enter the name of the catalog. This catalog is automatically associated with your database.
Create Click Create to create the database.

Limitations for SQL statements

  • Standard INSERT INTO statement is not supported.
  • SELECT statement is not supported if the table contains columns of type SMALLINT and TINYINT. (Applicable for version 2.0.0).
  • For the database-based catalogs, 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

  • 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.