3 CASSANDRA

============================================================================= Simba Cassandra ODBC Driver with SQL Connector Release Notes =============================================================================

The release notes provide details of enhancements, features, and known issues in Simba Cassandra ODBC Driver 2.5.5, as well as the version history.

2.5.5 =======================================================================

Released 2017-12-11

Enhancements & New Features

Prefixes for log file names

You can now configure the driver to prefix log file names with the user name associated with the connection and the process ID of the application through which the connection is made. To enable this feature, set the UseLogPrefix connection property to 1. For more information, see the Installation and Configuration Guide.
Performance improvement for DML queries

The driver has been upgraded to execute DML queries more quickly during batched insertions.

Resolved Issues The following issuse have been resolved in Simba Cassandra ODBC Driver 2.5.5.

The driver removes all semicolons (;) from queries when passing them to the data source, causing those queries to fail.

The driver now only strips semicolon characters from the end of queries.
Connection logs are unexpectedly overwritten by other connection logs.

Before, the driver was generating connection logs from 2 different loggers. The driver now generates connection logs from 1 logger only.

Known Issues The following are known issues that you may encounter due to limitations in the data source, the driver, or an application.

INSERT statement fails when inserting multiple rows and binding the DEFAULT value in the first row.

When inserting multiple rows in a single SQL statement and binding the DEFAULT value in the first row, the INSERT statement fails. As a workaround, use NULL instead of DEFAULT.
Non-key virtual table columns are not nullable.

Cassandra does not support null values in collections. The driver reports non-key columns in virtual tables as not nullable.
On Cassandra 1.2.x through 2.1.x, the driver returns incorrect values for VARINT (SQL_NUMERIC) columns.

This is due to a limitation in the Datastax cpp-driver. For more information, see the following link: https://datastax-oss.atlassian.net/browse/CPP-419
User-defined types have the following limitations:
- If a user-defined type is the primary key of a table, none of the primary key’s fields can be null when it is used in an INSERT statement.
- User-defined types cannot contain tuples, collections, or other user-defined types.
- A column name collision occurs if a map contains two user-defined types with identical field names, that is, if the map’s key and value are the same user-defined type.
- If a collection is nested in a user-defined type, the driver returns 0 for the collection column.

Version History =============================================================

2.5.4 ———————————————————————–

Released 2017-10-06

Resolved Issues The following issues have been resolved in Simba Cassandra ODBC Driver 2.5.4.

The driver consumes significantly more memory compared to earlier versions of the same driver.
When working with virtual tables, the driver terminates unexpectedly when doing the following:
- Writing a large number of rows to a virtual table.
- Reading or writing to a virtual table that represents a LIST type column.

2.5.3 ———————————————————————–

Released 2017-08-31

Enhancements & New Features

Asynchronous write

The driver now supports asynchronous write. To enable asynchronous write, set the EnableAsynchronousWrites configuration option to 1. For more information about the asynchronous write configuration options, see the Simba Cassandra ODBC Driver Install and Configuration Guide.
Disable decimal padding

You can now disable automatic decimal padding, and specify the default decimal scale for columns. To disable decimal padding, set the DisableDecimalPadding configuration option to 1. To specify the default decimal scale, set the DefaultColumnScale configuration option to the new default.
Upgrade to Datastax cpp-driver 2.7.0

The driver now uses version 2.7.0 of the Datastax cpp-driver.
New connection properties

Several new connection properties have been added to the driver. For more information about these connection properties, see the Simba Cassandra ODBC Driver Install and Configuration Guide.

Resolved Issues The following issue has been resolved in Simba Cassandra ODBC Driver 2.5.3.

The driver returns an error if the TOP operation is present in both the outer and the inner query.

2.5.2 ———————————————————————–

Released 2017-08-10

Enhancements & New Features

Default keyspace now used in SQLForeignKeys when no keyspace is specified

If SQLForeignKeys is called and no keyspace is specified, the driver now uses the default keyspace.
User-defined type as primary key

The driver now supports the use of Cassandra user-defined types as the primary key of a table.

Resolved Issues The following issues have been resolved in Simba Cassandra ODBC Driver 2.5.2.

If a user-defined type contains multiple fields, specific fields cannot be updated.
SQLForeignKeys incorrectly returns SQL_SUCCESS when used with incorrect case.

This issue has been resolved. SQLForeignKeys is now correctly treated as case-sensitive, and returns SQL_NODATA when used with incorrect case.
Driver terminates unexpectedly when converting reading TWDTime with value ‘00:00:00.000000000’.
COUNT does not respect case-sensitive naming.

2.5.1 ———————————————————————–

Released 2017-07-01

Resolved Issues The following issue was resolved in Simba Cassandra ODBC Driver 2.5.1.

Driver may terminate unexpectedly when reading or writing SQLColumns.

2.5.0 ———————————————————————–

Released 2017-05-31

Enhancements & New Features

Support for Cassandra user-defined types

The driver now supports Cassandra user-defined types, provided those types do not contain tuples, collections, or other user-defined types.

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