Tag: 12c

Advanced Replication

Long before Streams, long before Goldengate, if you want to keep data between sites synchronised in some fashion, or even allow sites to independently update their data, there was the Advanced Replication facility in Oracle.  An “extension” of the concept of simple materialized views…

Attribute clustering (part 3)

So in part1 and part2, we looked at creating tables with clustered data.  If you’re ready to climb aboard the attribute clustering heading toward Fastville you might want to take an existing table and cluster it.  In part 2 we saw how we had…

Attribute clustering (part 2)

In the previous post, I demonstrated attribute clustering by creating a table of source data which contained data in randomised order, via SQL> create table source_data as 2 select d.* 3 from dba_objects d 4 where object_id is not null 5 order by dbms_random.random;…

Attribute clustering (part 1)

One of the nice facilities in 12c is the ability to instruct the database to co-locate data during loading in order to facilitate reduced resource consumption for subsequent queries. Here’s an example of it in use. First I’ll create table SOURCE_DATA to mimic some…

Code enhancements without changing code

An interesting suggestion came through on AskTom this week, which prompted the following exploration. Let us assume you are populating a table with INSERT INTO EMP SELECT * FROM SOURCE_EMPS and it falls over with ORA-12899: value too large for column To capture the…

Exadata Express – I’m in !

Jumping into 12.2 on Exadata Express is made easy with the packaging up of the client configuration files.  Here’s what I had to do to get SQL Plus going into the database 1) Download the client credentials file from the Service Console 2) Unzip…

Securefile in 12c – part 2

In a previous post, I noted that the parameter db_securefile changes from PERMITTED in 11g, to PREFERRED in 12c.  Jonathan Lewis raised the interesting question of what happens when you upgrade to 12c from 11g, where a partitioned table may already have some basicfile…