Oracle

Creating a schema synonym in Oracle – an unsupported feature

By Franck Pachot . Ivica Arsov (@IvicaArsov) has made an interesting comment about AUDIT_ACTIONS object link table. I’ll blog about it soon, but in the meantime when checking its definition in cataudit.sql it came upon the following:(…)

Oracle lateral inline view, cursor expression and 12c implicit statement result

By Franck Pachot . I’ll present here 3 ways to run a query for each result of another query. Let’s take an exemple: get all executions plan (select from dbms_xplan.display_cursor) for each of my queries (identified from v$sql). The(…)

Oracle 12c: Can we disable logging for DML?

By Franck Pachot . If we don’t mind about loosing our changes, then can we disable logging for DML? This is a question I’ve heard a lot. Ok, you don’t need to recover your changes but Oracle may want(…)

SQL*Plus COPY Command is back as BRIDGE

By Franck Pachot . Did you ever use the COPY command in sqlplus? It’s very old, and documentation says : The COPY command is not being enhanced to handle datatypes or features introduced with, or after Oracle8i. The(…)

Oracle 12c: comparing TTS with noncdb_to_pdb

By Franck Pachot . How to migrate from non-CDB to CDB? Of course all known migration methods works. But there is also another solution: upgrade to 12c if necessary and then convert the non-CDB to a PDB. This is(…)

When Oracle resets session statistics

By Franck Pachot . During our Oracle 12c New Features workshop I had a very good question about whether the session statistics are reset or not when doing ALTER SESSION SET CONTAINER. My initial thought was that they(…)

Oracle 12c privilege analysis rocks

By Franck Pachot . 12c came with a very nice feature: privilege analysis. You don’t know which privileges are required? then just grant DBA, run your application, and check which minimal privileges are needed. And today, I’ve discovered how(…)

Oracle locks: Identifying blocking sessions

By Franck Pachot . When you have sessions blocked on locks, you probably have all information about the waiters (they call you and anyway their waiting session is visible in v$session our ASH). But you usually need to get(…)

12c SQL Plan Directive: state has changed between 12.1.0.1 and 12.1.0.2

By Franck Pachot . SQL plan Directives have been introduced in 12c. If you have scripts that check their states (and I have that as I prefer to monitor closely the features that are new) you probably have seen(…)

AWR does not store explain plan predicates

By Franck Pachot . What is the most important part in an execution plan? It’s probably the predicate section. It helps to see implicit conversions. It helps to understand why an index is used or not. Or to see(…)