This case study highlights the successful emergency restoration of a 100 GB PostgreSQL 9.5 database after a critical administrative error led to the accidental deletion of the entire database instance, including vital order history.

Client & Data Information

• Client Name: Confidential
• Data Type: PostgreSQL 9.5
• Data Capacity: 100 GB
• Primary Issue: Accidental Database Deletion (DROP DATABASE)
• Mission-Critical Data: Transactional Order Records

Incident Summary

During a routine maintenance window, an accidental operation resulted in the execution of a DROP DATABASE command on a production PostgreSQL server. This operation removed the logical links to the 100 GB database, rendering all order data invisible to the system. Since the deletion was logical, the operating system marked the file space as “free,” putting the data at high risk of being overwritten by new system writes.

Technical Analysis

Upon forensic analysis of the PostgreSQL storage partition, AS Data Recovery engineers identified:

• Storage Engine Persistence: PostgreSQL 9.5 uses a storage architecture where data is stored in fixed-size pages (typically 8KB). Even after a DROP command, the physical data “heaps” (the files in the base/ directory) often remain in the unallocated space of the disk until overwritten.
• Tuple Signatures: Every row (tuple) in PostgreSQL has a specific internal header ($xmin$, $xmax$, $ctid$). Our team looked for these binary signatures to identify “orphaned” order records.
• OID Mapping: The primary challenge was that the System Catalog (which maps table names to OIDs) was also deleted. We had to manually identify table structures based on column data types and patterns.

Recovery Solution

The recovery strategy utilized Low-Level Partition Carving via our proprietary sql110PGrecovery tool. Since the database files were logically deleted, our engineers bypassed the PostgreSQL service and scanned the raw disk sectors. By identifying the unique block headers of PostgreSQL data pages, we “carved” the order tables directly from the disk platters, effectively bypassing the missing system catalog.

Recovery Process

• Immediate Disk Isolation: The server was immediately powered down to prevent any background processes or WAL (Write-Ahead Logging) from overwriting the deleted order data.
• Forensic Partition Imaging: Created a sector-by-sector clone of the storage volume to perform the recovery on a safe, secondary environment.
• Low-Level Sector Scanning: Utilized the sql110PGrecovery tool to scan for PostgreSQL page signatures across the 100 GB partition.
• Table Structure Reconstruction: Manually reconstructed the schema for the order tables by analyzing the data types within the carved tuples (e.g., identifying timestamps, integer IDs, and text fields).
• Data Extraction & Verification: Extracted the records into SQL format and re-imported them into a fresh PostgreSQL instance, achieving 100% data integrity.

Recovery Results

• Recovery Integrity: 100% (Complete restoration of all deleted order records)
• Recovered Volume: 100 GB
• System Status: Data successfully migrated to a new production instance.
• Customer Satisfaction: Extremely Satisfied.

Expert Reminder from AS Data Recovery: In PostgreSQL, a DROP TABLE or DROP DATABASE command is a logical operation. The data is still there until new data takes its place. If you delete a table accidentally, stop the server immediately. Any further write activity—even log files—can destroy your chances of recovery. Contact AS Data Recovery professionals for low-level forensic carving.