Sql

Oracle CREATE DIRECTORY Command Explained The Oracle CREATE DIRECTORY command creates a directory object — a logical alias inside the Oracle database that points to a real folder on the server's file system. This is one of the most used setup steps for Oracle Data Pump exports and imports, UTL_FILE file operations, …

Oracle Data Pump: Create the DATA_PUMP_DIR Directory Before you can run any Oracle Data Pump export (expdp) or import (impdp) job, Oracle needs to know where to write and read dump files and log files on the server. You do this by creating a directory object inside the database that points to a real folder on the …

Oracle Flashback Query: Copy Historical Data Into a New Table Sometimes you need to go back in time and recover data the way it looked at a specific moment — without restoring the full database. Oracle makes this possible with Flashback Query, using the AS OF TIMESTAMP clause to read historical data directly from the …

How to Find the Current SCN in Oracle Database Using DBMS_FLASHBACK What number marks "now" inside an Oracle database? The System Change Number (SCN) does. One call to DBMS_FLASHBACK.GET_SYSTEM_CHANGE_NUMBER returns it from any session that has EXECUTE on the package. What Is an SCN? The System Change Number (SCN) is a …

How to Enable Oracle Database Flashback: Shutdown, Mount, and ALTER Commands Oracle Flashback Database is one of the most powerful data protection tools available to a DBA. This guide walks you through the four commands needed to turn on Oracle Flashback — from a clean shutdown to opening the database in flashback …

How to List Oracle Statspack Snapshots with SQL Query This Oracle Database query provides a simple way to view all Statspack snapshots stored in your database. Statspack is Oracle's built-in performance monitoring tool that captures database statistics at regular intervals, helping database administrators analyze …

Monitoring PGA Usage by Username in Oracle Database Purpose V$SESSTAT is the view that holds one statistic value per session, and two of its statistics describe how much Program Global Area (PGA) memory a session uses right now and the most it has used. The script below joins V$SESSTAT to V$STATNAME, filters the …

Oracle Database SGA Breakdown Script for Performance Monitoring Monitoring memory usage in an Oracle Database is one of the most important tasks for a DBA. The System Global Area (SGA) plays a crucial role in the performance of the database, as it stores data and control information used by Oracle processes. In this …

Oracle SQL Hash Lookup Query - Retrieving SQL Text from V$SQLAREA Purpose This Oracle Database query is designed to retrieve the SQL statement text (the first 1,000 characters) from the V$SQLAREA view using a specific hash value. This is particularly useful for database administrators and developers who need to …

Oracle Database: Find Query Hash Value Using V$SQLAREA Finding specific SQL queries in Oracle Database can be challenging when dealing with large systems running thousands of statements. This guide demonstrates how to efficiently locate query hash values using the V$SQLAREA system view by searching for unique text …