Install Oracle 12C Release 2 (12.2) on Oracle Linux 7 (OEL7)

This article presents how to install Oracle 12C(12.2) Release 2 on Oracle Enterprise Linux 7 (OEL7).

Read following article how to install Oracle Enterprise Linux 7: Install Oracle Linux 7 (OEL7) (for comfort set 4G memory for your virtual machine before proceeding with Oracle software installation).

Software

Software for 12CR2 is available on OTN or edelivery

Database software

linuxx64_12201_database.zip

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Enhanced LISTAGG Oracle Database 12C release 2 (12.2)

In previous releases there was always problem with function LISTAGG. If list of concatenated expression exceeds maximum length supported by VARCHAR2 type, then ORA-01489 is raised.

In new version Oracle Database Release 12.2 addressed this issue by adding extra clause ON OVERFLOW TRUNCATE to hide this error. In my opinion it’s not full solution but in some cases can be useful.

LISTAGG ( [ALL] <measure_column> [,<delimiter>] 
 [ON OVERFLOW TRUNCATE [truncate_literal] [WITH | WITHOUT COUNT] | 
  ON OVERFLOW ERROR]) 
WITHIN GROUP (ORDER BY <oby_expression_list>)

I recommend to read following article as well:

String concatenation aggregation methods

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