Review new features available with Oracle Database 19c.

COLOCATION_TAG Parameter

The COLOCATION_TAG parameter is an alphanumeric string that you can use with the CONNECT_DATA parameter of the TNS connect string. When you set the COLOCATION_TAG parameter, it attempts to route clients with the same COLOCATION_TAG to the same database instance.

Colocation of sessions on the same instance can help decrease inter-instance communication and thereby increase performance for workload that benefits from being executed in the same instance.

KERBEROS5_PRINCIPAL Parameter

When you configure Kerberos authentication for an Oracle Database client, you can use the KERBEROS5_PRINCIPAL parameter to specify multiple Kerberos principals with a single Oracle Database client. This is an optional parameter. When specified, it is used to verify if the principal name in the credential cache matches the parameter value.

Use this parameter with the CONNECT_DATA parameter. Alternatively, you can specify KERBEROS5_CC_NAME in the connect string along with the KERBEROS5_PRINCIPAL parameter to connect as a different Kerberos principal. Each Kerberos principal must have a valid credential cache.

These features are deprecated in this release and may be desupported in a future release.

Deprecation of the SERVICE_NAMES Initialization Parameter

Starting with Oracle Database 19c, customer use of the SERVICE_NAMES parameter is deprecated. It can be desupported in a future release.

The use of the SERVICE_NAMES parameter is no longer actively supported. It must not be used for high availability (HA) deployments. It is not supported to use service names parameter for any HA operations. This restriction includes FAN, load balancing, FAILOVER_TYPE, FAILOVER_RESTORE, SESSION_STATE_CONSISTENCY, and any other uses.

To manage your services, Oracle recommends that you use the SRVCTL or GDSCTL command line utilities, or the DBMS_SERVICE package.

Deprecation of Weak Native Network Encryption and Integrity Algorithms

The DES, DES40, 3DES112, 3DES168, RC4_40, RC4_56, RC4_128, RC4_256, and MD5 algorithms are deprecated in this release.

As a result of this deprecation, Oracle recommends that you review your network encryption and integrity configuration to check if you have specified any of the deprecated weak algorithms.

To transition your Oracle Database environment to use stronger algorithms, download and install the patch described in My Oracle Support note 2118136.2.