A year ago I wrote about the pitfalls ofNULL values in NOT INsubqueries. This time I wanted to keep promises I made back then, dig a little deeper and also look at NOT EXISTS as another type of subquery used to filter out records based on negative matches. Is there any semantic differe...
Before you begin: Log on as the UNIX user that owns the Oracle installation. On some operating systems, this user will not have the necessary permissions to run all of the commands and utilities called by RDA (e.g. sar, top, vmstat, etc). If you are running RDA to assist in resolvin...
The OCI and Server-Side Internal drivers still get better performance when the application uses . If your code is used with both the Thin and OCI drivers, you can disable the method when using the Thin by setting the connection property to . This will make a NOOP. Do not set this ...
In this release, an administrator must have both the Java and SOACS administrator roles in order to provision instances. You will encounter the following error if you attempt to provision with either (but not both) credentials: "User's role does not allow access to SOA Cloud Service". Scalin...
The function waits to receive data from the socket until either at least one byte is available in the socket or the specified time has elapsed.Syntax int net_read (SYS_NETFD sd, char *buf, int sz, int timeout);Return Values The number of bytes read, which will not exceed the maximum...
Performance:Reactive Streams Ingest (RSI) for streaming data into the Oracle Database (21c and later); Oracle connection manager (CMAN) in traffic director mode (CMAN-TDM) High Availability:Transparent Application Continuity (TAC); AC support in DRCP; and AC support for legacy Oracle JDBC types...
Ooops, this is not good. Is this index really not being used, is it really perhaps safe to drop. Let’s find out: SQL> drop index kiddie_fk_i; Index dropped. Let’s now delete another parent row and see if we notice a difference in performance: SQL> delete daddy where id = 3;...
Workloads change and in recent years, transactional systems have morphed into hybrid environments with higher IO workloads and better chipsets have offered us better performance with less demand on upgrades. Considering the above list, we’re now aware that around 85% of Oracle work...
This is not only cumbersome, it also results in very poor performance—a true anti-pattern. However, turning rows into columns is the pivot problem in its purest form. Therefore, these steps should be followed again: (1) use group by to reduce the rows to one row per entity, (2) use...
In Oracle Database 19c, I’ve not been able to get an AI created at all. In Oracle Database 21c, the best I’ve seen has been a Unusable/Invisible AI:1 2 3 4 5 6 7 8 9 10 11 12 13 14 SQL> select index_name, index_type, auto, constraint_index, visibility, status, num_...