Oracle CBO performs transitivity as the first step in optimization. Transitivity means generating additional predicates based on existing predicates. The main advantage is the inclusion of extra access methods. Transitivity is not done for join predicates.

Assume A, B, and C are columns. If A=5 and A=B, you can conclude that B=5. This can be applied to queries as shown on the following page. Note that A=5 contains a constant.
However, in terms of joins, if A=B and B=C, it is not concluded that A=C; in other words, the Oracle server does not generate transitive closures for join predicates.
For more details about transitivity, see Doc ID 68979.1


MV2OCI is a new tool is permitting the load data and migration from “on-premises” to Oracle Cloud Database leveraging on Oracle Data Pump and within one command. Data Pump Import lets you import data from Data Pump files residing on the Oracle Cloud Database node.
For more information see Doc ID 2514026.1.

For all offerings using Oracle Database 19c or later, if you are not licensed for Oracle Multitenant, then you may have up to 3 user-created PDBs in a given container database at any time. For all offerings using Oracle Database 12.1 through 18c, if you are not licensed for Oracle Multitenant, then the container database architecture is available in single-tenant mode, that is, with one user-created PDB, one user-created application root, and one user-created proxy PDB.

EE: Extra cost option; if you are licensed for Oracle Multitenant, then you can create up to 252 PDBs.

ODA and Exa: Extra cost option; if you are licensed for Oracle Multitenant, then you can create up to 4096 PDBs.

ExaCS/CC, DBCS EE-HP, and DBCS EE-EP: Included option; you can create up to 4096 PDBs.

Starting with the Oracle Database 21c release, an application can change its database passwords without an administrator having to schedule downtime. To accomplish this, a database administrator can associate a profile having a non-zero limit for the PASSWORD_ROLLOVER_TIME password profile parameter, new with this release, with an application schema. This allows the database password of the application used to be altered while allowing the older password to remain valid for the time specified by the PASSWORD_ROLLOVER_TIME limit. During the rollover period of time, the application instance can use either the old password or the new password to connect to the database server. When the rollover time expires, only the new password is allowed. It is an Oracle 21c feature backported to Oracle 19.12 RU.

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Error signaling Function: koklnflushint

The fix for 32008819 is first included in (APR 2021) DB Release Update(DB RU)

Oracle has released its Critical Patch Update for July 2021 to address 327 vulnerabilities across multiple products. A remote attacker could exploit some of these vulnerabilities to take control of an affected system. CISA encourages users and administrators to review the Oracle July 2021 Critical Patch Update and apply the necessary updates.