Oracle DBA Learning Series Topic 3

Oracle DBA Learning Series

Topic 3: PFILE & SPFILE

Oracle databases use initialization parameter files to start the instance. These can be PFILE or SPFILE.
🔹 PFILE (Parameter File)
• Text file (init.ora)
• Edited manually
• Changes need DB restart
• Good for troubleshooting & recovery
🔹 SPFILE (Server Parameter File)
• Binary file (spfile.ora)
• Managed by Oracle automatically
• Supports dynamic parameter changes
• Required for RAC & recommended for production
LOCATION: PFILE and SPFILE are located in $ORACLE_HOME/dbs on Unix/Linux and %ORACLE_HOME%\database on Windows; in ASM environments, SPFILE is stored inside ASM disk groups.
🔹 DBA Tips
1)Use SPFILE in production environments
2) Keep a PFILE backup for emergency startup
3) Convert easily when needed
4)Oracle database needs the SPFILE (or PFILE) to start, as it contains all initialization parameters required to create the instance.

Let’s keep learning! 🚀

Oracle DBA Learning Series Topic 2

 Oracle DBA Learning Series

Topic 2: Shared Pool

The Shared Pool is a key part of the SGA that helps Oracle improve performance by reusing SQL and PL/SQL code instead of parsing it again and again.
The size of the shared pool is defined by initialization parameter SHARED_POOL_SIZE in parameter file.
🔹 What the Shared Pool stores
✔ Parsed SQL & execution plans
✔ PL/SQL procedures & functions
✔ Data dictionary cache
🔹 Why it matters to DBAs
✅ Reduces hard parsing
✅ Improves query performance
✅ Saves CPU and memory
DBA Tip:
If the shared pool is too small, you may see library cache misses and frequent hard parses.

Let’s keep learning! 🚀

Oracle DBA Learning Series Topic 1

Oracle DBA Learning Series

Topic 1: Bigfile Tablespace

Bigfile Tablespace is designed to simplify storage management in large Oracle databases.
Instead of managing many small datafiles, DBAs can work with one very large datafile, making scaling and administration easier.
🔹 Things to keep in mind
⚠ Single datafile = higher impact if corrupted
⚠ Backup & restore may take longer

CREATE BIGFILE TABLESPACE bft_ts
DATAFILE '+DATA' SIZE 10G AUTOEXTEND ON;
SELECT tablespace_name, bigfile FROM dba_tablespaces;

📌 DBA Tip:
Use Bigfile Tablespaces for large, fast-growing databases and Smallfile Tablespaces when fine control is needed.

Let’s learn and grow together! 🚀