Why should you care?

Production outages and slow systems are diagnosed with sga & pga knowledge — not guesswork.

See it live — copy this example

Run these statements in SQL Developer or SQL*Plus against your lab PDB. Prefer a practice user — not SYS — for application SQL.

SHOW PARAMETER sga_target
SHOW PARAMETER pga_aggregate_target

SELECT name, value FROM v$parameter
WHERE name IN ('sga_target','pga_aggregate_target');

What happened?

• SGA is shared memory for the instance.
• PGA is private memory per server process.

Practice next

1. Connect to your lab as a user with the needed privileges.
2. Run the read-only checks first.
3. Write the definition of this topic in your own words.
4. Change one literal in the example and re-run.
5. Write a second example from memory without looking.

Remember

You can explain SGA & PGA in plain English. You ran at least one related command or query. You know one real system where it matters.

SGA & PGA on a banking PDB

On-call DBA reviews sga & pga during a health check before peak traffic.

Outcome: You know which view/command to open first.