• [CPP-393] Allow prepared statements to be prepared on all nodes
• [CPP-394] Prepare statements on UP/ADD events
• [CPP-439] Support OpenSSL 1.1
• [CPP-512] Include hash of result set metadata in prepared statement id
• [CPP-528] Per-query (and per-batch) keyspace support

• [CPP-368] API Functions that take strings now check for NULL and replace it with an empty string
• [CPP-438] Broken build with GCC 7 and OpenSSL 1.1
• [CPP-501] Schema metadata is corrupted when views and indexes exist for a table
• [CPP-503] Schema meta race condition when a view is dropped from a table
• [CPP-535] Schema metadata views are not properly updated during drop event
• [CPP-540] NULL columns in table/view metadata caused by side-effect in a compiled out assertion
• [CPP-543] Fix dllimport/dllexport
• [CPP-546] Result metadata callback casting requests to invalid types
• [CPP-547] Pool request callback attempting to return a deleted connection

• [CPP-432] Removed dense table 'empty' columns from metadata
• [CPP-449] Update vc_build.bat to include automated build for Visual Studio 2017
• [CPP-478] Renamed the class SpeculativeExecution to RequestExection to reduce confusion when it appears in driver logs
• [CPP-523] Use arc4random or getrandom instead of /dev/urandom (if available)
• [CPP-526] Add a mutable wrapper around the request object
• [CPP-538] Deprecate watermarks

• [CPP-473] Missing symbol cass_cluster_set_queue_size_log
• [CPP-486] Compiler warning 'implicit-fallthrough' causing build errors
• [CPP-491] Unintentional switch case fallthrough in RequestCallback
• [CPP-496] CassWriteType CDC and VIEW missing
• [CPP-502] Incorrectly exported symbols cass_error_result_responses_received / required
• [CPP-513] Copy-on-write keyspace logic is incorrect
• [CPP-514] Prepared Statement Crash

• Added beta support for protocol v5 which can be enabled using cass_cluster_set_use_beta_protocol_version()

• Duration type needs to use int64_t for the nanos component (CPP-454)
• Heavy load when updating token maps on node addition (CPP-460)
• Adding a node breaks token map reconstruction (and can cause long delays) (CPP-464)

• Added duration type support via cass_statement_bind_duration[by_name](), cass_collection_append_duration(), cass_tuple_set_duration(), cass_user_type_set_duration[by_name]() and cass_value_get_duration()

• Added process information (pid) to UUID node hash (CPP-354)
• Fixed documentation mismatch with default consistency (CPP-383)
• Fixed issue where an invalid keyspace could cause a session to hang indefinitely during the connection process (CPP-384)
• Fixed issue where an invalid local datacenter (DC-aware policy) could cause a session to hang indefinitely during the connection process (CPP-398)
• Fixed issue where SSL errors would prevent connections from reconnecting (CPP-408)
• Made the client-side timestamp generator fully monotonic (CPP-412)
• Fixed issue where an invalid value type, CASS_VALUE_TYPE_INT, was returned for org.apache.cassandra.db.marshal.IntegerType instead of CASS_VALUE_TYPE_VARINT (CPP-419)
• Fixed issue where single quote custom types (e.g. 'org.apache.cassandra.db.marshal.LexicalUUIDType') would be incorrectly returned as a UDT data type instead of as a custom data type (CPP-431)

October 20, 2016

• Added constant speculative execution which preemptively runs multiple of the same query in an effort to smooth out latency spikes.
• Added idempotent queries to support speculative execution and allow automatic retries. Use cass_statement_set_is_idempotent() or cass_batch_set_is_idempotent().
• SSL can be now be used without initializing the underlying implementation (e.g. OpenSSL). Use cass_ssl_new_no_lib_init().

• Fixed an issue where a connection is incorrectly marked READY after it''s already been marked DEFUNCT (CPP-401)
• Fixed pointer aliasing issues in cass::Address (CPP-406)
• Fixed an issue where random partitioner hash values were being incorrectly generated (CPP-403)

August 22, 2016

• Contact points are now randomized by default (CPP-193)
• Token-aware routing can be used without enabling schema metadata (CPP-387)
• Multiple IP addresses can be resolved from a single domain (CPP-364)

• Fixed issue that would cause quadratic ring processing with invalid replication factors (CPP-298)
• Fixed issue where schema change handler could hang if an error is returned by Cassandra (CPP-381)
• Fixed crash caused by connecting separate sessions in multiple threads (CPP-385)
• Fixed issue where the control connection could timeout as a result of schema or token map processing (CPP-388)
• Greatly improved the performance of building the token map for token aware routing (CPP-389)
• Fixed issue where heartbeats were restarted on unresponsive connections and prevented the connection from being terminated (CPP-392)

June 24, 2016

• Added the per-request timeouts to statement and batch
• Added the ability to remove custom payload items

• Fixed issue where cass_date_time_to_epoch() unable to handle dates before Cassandra date epoch (value: 2147483648)

June 9, 2016

• Fixed issue where cass_future_get_result() and similar methods would dereference a NULL pointer if a future is set to an error.

June 1, 2016

• Added the ability to add a custom SASL authenticator
• Added reverse DNS lookup for IP addresses which can be enabled using cass_cluster_set_use_hostname_resolution().
• Added a DNS resolve timeout that can be set using cass_cluster_set_resolve_timeout().
• Added the ability for SSL peer identity to be verified by hostname. (CASS_SSL_VERIFY_PEER_IDENTITY_DNS)
• Added the ability to bind/set/append custom types with a class name.
• Added CassStatement function to clear/resize parameters cass_statement_reset_parameters().

• Fixed crash caused by tables with the same name in adjacent keyspaces.
• Fixed an invalid memory read in processing strategy options metadata.
• Fixed issue where null values didn''t have proper datatypes.
• Fixed issue where an "UP" event could cause the session connection process to hang.
• Reduced reconnection log chatter at the CASS_LOG_ERROR level. A failed reconnection attempt is only logged one time as an error.

March 14, 2016

• Added support for materialized view schema metadata.
• Added support for secondary index schema metadata.
• Added cluster key order to table schema metadata via cass_table_meta_clustering_key_order().
• Added frozen flag to CassDataType via cass_data_type_is_frozen().
• Added support getting the connected cluster''s Cassandra version via cass_schema_meta_version().
• Added blacklist, whitelist DC, and blacklist DC load balancing policies. Thanks to Walid Aitamer (waitamer).

• Fixed the control connection to only become "ready" during the initial connection process.
• Fixed assertion in data type comparison for collection/tuple types.
• Fixed reference count issue in cass_collection_new_from_data_type()
• Fixed retry consistency levels for batches. Batches now correctly use the downgraded consistency levels supplied from retry policies.
• Fixed function name typo: cass_data_sub_type_count() to cass_data_type_sub_type_count(). The old spelling is still present, but deprecated.
• Fixed cass::VersionNumber to handle tick-tock release version where only "major.minor" are provided.
• Fixed function cass_session_connect_keyspace() to correctly return an error when the keyspace is invalid.
• Fixed invalid logic in schema metadata swap method which could cause unnecessary copy-on-writes.
• Fixed bottleneck in cass::Session by using copy-on-write instead of a highly contended lock to track the current keyspace.
• Changed "major/minor" to "major_version/minor_version" in cass::VersionNumber to avoid naming conflicts on some platforms.

December 14, 2015

• Added basic support for Cassandra 3.0. The driver supports Cassandra 3.0 schema metadata for keyspaces, tables, columns, user types, functions, and aggregates.

• Changed the default consistency from CASS_CONSISTENCY_LOCAL_QUORUM to CASS_CONSISTENCY_LOCAL_ONE

November 19, 2015

• Fixed issue where cass_data_type_sub_data_type() was always referencing a NULL pointer
• Fixed cass::Atomic (intrinsic) for 32-bit MSVC

October 29, 2015

• Refactored the schema metadata API (CassSchema) to use concrete types (CassKeyspaceMeta, CassTableMeta, etc.) instead of the single CassSchemaMeta type.
• Added support for UDF/UDA schema metadata
• Added support for whitelist filtering i.e. whitelist load balancing policy

• Fixed Address::compare() issue that cause invalid comparisons for IPv4
• Fixed issue that caused StreamManager to generate invalid stream IDs in Windows release builds.
• Fixed issue where cass_cluster_set_protocol_version() would return an error for protocol versions higher than v3
• Changed the default consistency from CASS_CONSISTENCY_ONE to CASS_CONSISTENCY_LOCAL_QUORUM
• When using prepared statements with protocol v4 (and higher) the driver will use partition key metadata returned in the prepared response instead of using schema metadata.
• Improved the performance of UUID to string and UUID from string conversions

September 21, 2015

• Added support for Cassandra 2.2 data types tinyint and smallint (cass_int8_t and cass_int16_t)
• Added cass_uint32_t support for the Cassandra 2.2 date data type
• Added functions to convert from Unix Epoch time (in seconds) to and from the Cassandra date and time types
• Added support for sending and recieving custom payloads to and from Cassandra
• Added support for server-side warnings
• Added new error response functions to handle the 'Read_failure', 'Write_failure', 'Function_failure', and 'Already_exists' errors

• Fixed SSL ring buffer memory leak
• Fixed potential memory issue caused by using named parameters
• Fixed hanging issue when calling cass_session_get_metrics()
• Fixed hanging issue caused by cass::MPMCQueue memory race
• Fixed invalid state assertion in cass::Handler
• Fixed UDTs with text fields
• A value of null is no longer implicitly used for unbound statement parameters. An error is returned (CASS_ERROR_LIB_PARAMETER_UNSET) for Cassandra 2.1 and earlier or the UNSET value is used for Cassandra 2.2 and later

August 11, 2015

• Added support for retry policies
• Added support for client-side timestamps
• Exposed raw paging state token via cass_result_paging_state_token() and it can be added to a statement using cass_statement_set_paging_state_token()
• Added support for enabling/disabling schema metadata using cass_cluster_set_use_schema()

• Connections that timeout will not disconnect an entire connection pool
• TCP_NODELAY is enabled by default
• Connections now support using 32,767 stream IDs when using the CQL Native Protocol v3
• cass_uuid_min_from_time() and cass_uuid_max_from_time() now correctly considers the time parameter as epoch time

July 7, 2015

• Added support for tuples and UDTs
• Added support for nested collections
• Added support for named parameters when using simple queries (non-prepared)
• Added support for protocol version 3 (and schema changes)

• Fixed SSL error handling
• Added libuv read buffer caching in cass::Connection

May 15, 2015

• Removed logging thread. cass_log_cleanup() and cass_log_set_queue_size() are now deprecated. A logging callback registered with cass_log_set_callback() will now be called on mulitple threads concurrently.
• Fixed an issue where the driver might crash/hang when system.local contains no entries
• Fixed an issue where the driver might hang under high-load due to missing memory fence before uv_async_send() in cass::AsyncQueue::enqueue()

April 23, 2015

• Added latency-aware load balancing. To enable use: cass_cluster_set_latency_aware_routing()
• Added performance metrics. To get metrics use: cass_session_get_metrics()
• Added CassInet string conversion functions: cass_inet_string() and cass_inet_to_string()

• Removed internal dependency on Boost. Optional: Boost Atomic can still be used as an implementation for internal atomic operations and memory fences.
• Removed wrapper types CassString, CassBytes and CassDecimal
• Added string length functions (functions with the suffix "_n") for all functions that previously took a null-terminated or CassString parameter.
• Added missing cass_statement_bind_null_by_name() function
• Fixed issue where time-based UUIDs (CassUuid v4) had the incorrect time on 32-bit systems

Mar 2, 2015

• Added testing documentation
• Added documentation for the varint data type
• Added a contributing document
• Added version defines to cassandra.h
• Fixed an issue where connections were attempted against decommissioned nodes
• Fixed an issue where an invalid key index was used for a single entry token-aware routing key
• Improved build error output when an incompatible version of Boost is used to build the driver

Feb 2, 2015

• Libuv 1.x supported

• cass_cluster_set_num_threads_io() now returns an error code
• Fixed an issue where a node in a remote DC could reconnect even if it was supposed to be ignored.
• Reduced the defaults for IO worker threads (1), core connections (1), and max connections (2).
• Fixed crash caused by a null token-aware key value.

Dec 22, 2014

• Added global logging. Logging is no longer configured per session.
• DC-aware load balancing policy is now the default and uses the DC of the first connected contact point. The DC-aware policy now has settings to control the number of remote hosts used in each DC (after exhausting the hosts in the local DC) and whether to ignore local consistency levels.
• Added socket options for TCP nodelay and keepalive: cass_cluster_set_tcp_nodelay() and cass_cluster_set_tcp_keepalive().

• CassSession objects must now be explicitly allocated/freed using cass_session_new() and cass_session_free(). cass_cluster_connect() has been removed and replaced by cass_session_connect().
• SIGPIPE is ignored on driver threads
• Connection timeout now covers the entire connection handshake instead of just the socket connection.
• UUID API has been updated to use explict state via CassUuidGen instead of using internal global state. See cass_uuid_gen_new() and corresponding functions.

Nov 20, 2014

• Added SSL support
• Added token-aware load balancing. It''s enabled by default. It can be disable using cass_cluster_set_token_aware_routing().
• Added functions to get schema metadata, cass_session_get_schema() can be use to get a snapshot of the schema metadata and cass_meta_*() functions can be used to retrieve detailed information about keyspaces, tables, and columns.

• Significantly improved request throughput by batching socket writes. Batch sizes can be configured using the function cass_cluster_set_max_requests_per_flush(). The default is 128 because the maximum write size is bounded by the number of pipelined requests per connection (for version 1 and 2 of the native protocol).
• Added backpressure mechanism that can be configured for by the number of outstanding bytes and the number of requests on a connection. These can be configured using cass_cluster_set_write_bytes_high_water_mark(), cass_cluster_set_write_bytes_low_water_mark(), cass_cluster_set_pending_requests_high_water_mark(), and cass_cluster_set_pending_requests_low_water_mark().
• Fixed a crash caused by a request timing out followed by a call to the connection read callback then the write callback.
• Fixed an issue that prevented the driver from recovering from a full cluster outage.
• Fixed an issue that allowed uv_queue_work() to be called from an application thread.
• Added logic to prevent redundant node refreshes when establishing a new connection from multiple IO workers.
• Fixed a crash caused by Cassandra 2.1.0 not returning metadata on execute requests.
• Fixed a memory leak that could leak request handlers if the control connection ran out of stream ids.
• Fixed a crash caused by calling an invalid timeout callback when waiting for connection to become available in a pool.
• Build will use an external version of Boost if present.

Sep 11, 2014

• Added node discovery and now handle topology/status change events
• Queries that modify schema wait for cluster schema agreement
• Added DC aware load balancing policy. The default policy is set to round robin.
• Added new methods to configure the load balancing policy, cass_cluster_set_load_balance_round_robin() and cass_cluster_set_load_balance_dc_aware()
• It is now possible for a session future to return an error when connecting to a cluster. This can occur when the driver is unable to connect to any contact points or the provided authentication credentials are invalid.

Aug 13, 2014

• Added callbacks to futures, cass_future_set_callback()
• Added plaintext authentication support, cass_cluster_set_credentials()
• Added map iterator, cass_iterator_from_map(), key and value pairs can be retrieved using cass_iterator_get_map_key() and cass_iterator_get_map_value()
• Values can be bound by name (statements created from prepared statements only)
• Values can be retrieved by name from result sets

• Reduced overhead of prepared statements
• Small performance improvement for all queries via reduced allocations

Jul 17, 2014

• Removed C 1x dependency
• Support for Cassandra 1.2 (native protocol version 1)
• Support for automatic paging
• Added method to set serial consistency on statement
• Added batch type to batches
• Exposed options cass_cluster_set_max_pending_requests(), cass_cluster_set_max_simultaneous_creation(), and cass_cluster_set_max_simultaneous_requests_threshold()
• Added cass_result_column_name() to get column name from a result set

• Fixed StreamManager so it no longer causes stack corruption
• Fixed issue where connections would log "'Timed out during startup' error on startup for ..." when a Session was closed while a connection was during its startup process
• Fixed Row and collections iterator so they return the first and last item properly
• Improved logic for creating new connections so it''s based on request throughput

• Removed the setopt method added set methods for all options
• Removed the getopt method
• cass_batch_new() and cass_collection_new() no longer take a consistency parameter
• cass_collection_new() now requires a collection type parameter
• is_map parameter removed from cass_statement_bind_collection()

Jun 16, 2014

• Support for Cassandra 2.0 (native protocol version 2)
• Support for prepared and batch statements
• Support for collections