DBA

English

Understanding NULL in Oracle Database

In Oracle Database, NULL signifies that a "value is unknown" or in a "state of absence." This is different from "zero" a...
Date and Time Data_en

How to Convert Strings to Datetime Data

In Oracle Database, converting strings to datetime data types is a crucial task. For example, converting date strings im...
Oracle Basics_en

Explaining the Oracle dual Table!

When working with the Oracle database, the dual table is an entity you will almost certainly encounter. While its name m...
Data Types_en

Mastering Oracle Table Creation and Data Types

Creating tables in an Oracle database is fundamental to efficient data management. This article provides a detailed expl...
English

Explaining the Basics of the Oracle SELECT Statement

The SELECT statement is the most basic and important SQL statement for operating an Oracle database. It allows you to ex...
English

Sample Tables and JOIN Examples for Hands-on Oracle Practice

When learning to operate an Oracle database, creating sample tables and manipulating data is extremely effective. This a...
English

A Beginner’s Guide to SQL*Loader

SQL*Loader is an essential tool for efficiently loading large volumes of data into an Oracle database. This article prov...
English

Explaining the ORA-1555 Error: Causes, Solutions, and Prevention

If you operate an Oracle database, you may have experienced the headache of the "ORA-1555: snapshot too old" error. This...
English

Guide to UNDO Tablespaces and UNDO Segments

To properly operate an Oracle database, understanding the UNDO tablespace and UNDO segments is essential. This article i...
English

Explanation of Permanent Segments, UNDO Segments, and Temporary Segments

In an Oracle database, segments are essential components for storing data, managing transactions, and performing tempora...
English

Oracle Net Configuration Guide

Oracle Net is the network service that connects databases and clients, and it is a critical mechanism for enabling remot...
English

How to Write and Configure Oracle tnsnames.ora [A Beginner’s Guide]

Are you struggling with how to write or configure the tnsnames.ora file, which is essential for connecting to an Oracle ...
English

Oracle Listener Monitoring and Performance Optimization

The Oracle Listener is a crucial component that manages connections between clients and the database. This article delve...
English

The Oracle Listener: A Complete Guide from Basics to Best Practices

"Having trouble with smooth database connections?"Have you ever faced this problem? The key to solving it is the Oracle ...
English

A Complete Explanation of Segment Shrink vs. DELETE/TRUNCATE Behavior

Efficient operation of Oracle Database requires freeing unnecessary space and optimizing performance. At the core of thi...
English

Oracle Database Segment Extension — Error Handling and Best Practices

In Oracle Database, as data grows, segments can run short of space, which may trigger errors and degrade performance. Th...
English

What Are Deferred Segments? Usage and Caveats

In Oracle Database, when you create a table, a segment (the physical storage area for data) is usually allocated immedia...
English

Explaining Segment Management in Oracle Database

To improve the operational efficiency of a database, you need to optimize storage management. At the center of that is s...
Performance_en

Oracle SQL Tuning Quick Guide: Execution Plans, Statistics, and Tracing [19c]

This article is a rewritten, more practical, and reproducible version of the original “Oracle SQL Tuning Basics.” While ...
English

Row Migration & Row Chaining — Understand Causes, Detection, and Remedies in One Go (Oracle)

To solve database performance issues, you must understand row migration and row chaining. This article digs into both co...