Why Local Undo is required We have global or shared undo for the entire CDB till 12c R1. With shared undo, before performing operations such as (cold) clone or unplug, it is necessary for the database to check for any uncommitted transactions in the source PDB. This is to avoid problems with transactional consistency in …

Local Undo in Oracle Database 12c R2(12.2)/19c and above Read More »

What is UNDO? How to monitor the usage of UNDO tablespace (1)Check allocated space and free space for UNDO tablespace. SELECT /* + RULE */ df.tablespace_name “Tablespace”,df.bytes / (1024 * 1024) “Size (MB)”,SUM(fs.bytes) / (1024 * 1024) “Free (MB)”,Nvl(Round(SUM(fs.bytes) * 100 / df.bytes),1) “% Free”,Round((df.bytes – SUM(fs.bytes)) * 100 / df.bytes) “% Used”FROM dba_free_space fs,(SELECT …

How to check undo tablespace in Oracle : Size , Usage Read More »

Oracle 23c is the latest Release of the Oracle Database. This is also a Long term release. It is also called Oracle 23ai given the focus on AI in it. Oracle has introduced a lot of new features in it. Here are the Top Features Augmenting a new generation of AI models Asking questions naturally …

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We saw how to enable trace in Oracle in an earlier post. The trace files obtained from the method are in raw  form which can be converted into a more readable format using the tkprof utility  in Oracle (Transient Kernel PROFile  utility) tkprof utility in Oracle The syntax is given below tkprofUsage: tkprof tracefile outputfile …

Oracle tkprof utility : How to generate and read Read More »