Oracle RMAN Multi-Section Feature

RMAN can optionally break up large files into sections and back up and restore these sections independently. This feature is built into RMAN. You can use it by creating multisection backups, which break up the files generated for the backup set into separate files. This can be done for backup sets and image copies. Each … Continue reading Oracle RMAN Multi-Section Feature

Change “Value” Column Width for “show parameter” in sqlplus

If you tried to increase the width of the "VALUE" column, nothing changed: I found that the NAME & Value columns have special names (for type column , it is normal): column NAME_COL_PLUS_SHOW_PARAM format A20column VALUE_COL_PLUS_SHOW_PARAM format A80 Now, it is fine.

What is the difference between Oracle Client 19c and Oracle Client Home 19c?

When I tried to download and install Oracle client 19c, it was my surprise that there are two different versions. See the following information from the oracle site: So, what is the difference between these two versions?. After some research I found that: LINUX.X64_193000_client.zip is the normal (before 19c) installer-based client software, where you can choose … Continue reading What is the difference between Oracle Client 19c and Oracle Client Home 19c?

TNS-04012: Unable to start Oracle Connection Manager instance.

Background: One advantage of the "Connection Manager" is that it can act as if a proxy server between the database client and the database server, especially when there is a firewall between the client and the server.I installed Oracle Client 19c (only the "Connection Manager" and the "Oracle Net Listener" components): https://www.youtube.com/watch?v=R-tSVkRckfs Then I configured … Continue reading TNS-04012: Unable to start Oracle Connection Manager instance.

Back to Basics – What is the Difference between Selection and Projection?

These concepts are related to the sql statement in oracle and in RDBMS in general. Projection This is a vertical subset of table columns (the select list) , including all rows.It may include one column, two columns or all table columns.Projection answers the question: which columns the query shall return? For example:select empno , ename, … Continue reading Back to Basics – What is the Difference between Selection and Projection?