I knew in Oracle 11g with Automatic Memory Management (AMM), the database was able to give unused memory back to the OS, controlled by MEMORY_TARGET and MEMORY_MAX_TARGET.

This mechanism is present in 11g since day 1 (in 2007), but I never actually played with it.


The Oracle documents state the following:

MEMORY_TARGET specifies the Oracle system-wide usable memory.
MEMORY_MAX_TARGET (…) decide on a maximum amount of memory that you would want to allocate to the database for the foreseeable future.

So my guess is, MEMORY_MAX_TARGET (static) is the maximum you can set MEMORY_TARGET (dynamic) to. A couple of days ago, I wanted to experiment a bit with these memory settings.

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create database: “ORA-01991: invalid password file” and “ORA-01403: no data found”

Last week I created a new database (Oracle 9.2) and got the following message when the ‘create database’ script was almost finished: ORA-01991: invalid password file.

OK, the database instance existed before, so I created a new password file with orapwd. Trying to open the database after this gave me the following message: ORA-01403: no data found. Continue reading