tg-delete-kg-core

Permanently removes a knowledge core from the TrustGraph system.

Synopsis

tg-delete-kg-core --id CORE_ID [options]

Description

The tg-delete-kg-core command permanently removes a stored knowledge core from the TrustGraph system. This operation is irreversible and will delete all RDF triples, graph embeddings, and metadata associated with the specified knowledge core.

Warning: This operation permanently deletes data. Ensure you have backups if the knowledge core might be needed in the future.

Options

Required Arguments

• --id, --identifier CORE_ID: Identifier of the knowledge core to delete

Optional Arguments

• -u, --api-url URL: TrustGraph API URL (default: $TRUSTGRAPH_URL or http://localhost:8088/)
• -U, --user USER: User identifier (default: trustgraph)

Examples

Delete Specific Knowledge Core

tg-delete-kg-core --id "old-research-data"

Delete with Specific User

tg-delete-kg-core --id "test-knowledge" -U developer

Using Custom API URL

tg-delete-kg-core --id "obsolete-core" -u http://production:8088/

Prerequisites

Knowledge Core Must Exist

Verify the knowledge core exists before deletion:

# Check available knowledge cores
tg-show-kg-cores

# Ensure the core exists
tg-show-kg-cores | grep "target-core-id"

Backup Important Data

Create backups before deletion:

# Export knowledge core before deletion
tg-get-kg-core --id "important-core" -o backup.msgpack

# Then proceed with deletion
tg-delete-kg-core --id "important-core"

Safety Considerations

Unload from Flows First

Unload the knowledge core from any active flows:

# Check which flows might be using the core
tg-show-flows

# Unload from active flows
tg-unload-kg-core --id "target-core" --flow-id "active-flow"

# Then delete the core
tg-delete-kg-core --id "target-core"

Verify Dependencies

Check if other systems depend on the knowledge core:

# Search for references in flow configurations
tg-show-config | grep "target-core"

# Check processing history
tg-show-library-processing | grep "target-core"

Deletion Process

1. Validation: Verifies knowledge core exists and user has permission
2. Dependency Check: Ensures core is not actively loaded in flows
3. Data Removal: Permanently deletes RDF triples and graph embeddings
4. Metadata Cleanup: Removes all associated metadata and references
5. Index Updates: Updates system indexes to reflect deletion

Output

Successful deletion typically produces no output:

# Delete core (no output expected on success)
tg-delete-kg-core --id "test-core"

# Verify deletion
tg-show-kg-cores | grep "test-core"
# Should return no results

Error Handling

Knowledge Core Not Found

Exception: Knowledge core 'invalid-core' not found

Solution: Check available cores with tg-show-kg-cores and verify the core ID.

Permission Denied

Exception: Access denied to knowledge core

Solution: Verify user permissions and ownership of the knowledge core.

Core In Use

Exception: Knowledge core is currently loaded in active flows

Solution: Unload the core from all flows before deletion using tg-unload-kg-core.

Connection Errors

Exception: Connection refused

Solution: Check the API URL and ensure TrustGraph is running.

Deletion Verification

Confirm Deletion

# Verify core no longer exists
tg-show-kg-cores | grep "deleted-core-id"

# Should return no results if successfully deleted
echo $?  # Should be 1 (not found)

Check Flow Impact

# Verify flows are not affected
tg-show-flows

# Test that queries still work for remaining knowledge
tg-invoke-graph-rag -q "test query" -f remaining-flow

Environment Variables

• TRUSTGRAPH_URL: Default API URL

Related Commands

• tg-show-kg-cores - List available knowledge cores
• tg-get-kg-core - Export knowledge core for backup
• tg-unload-kg-core - Unload core from flows
• tg-put-kg-core - Store new knowledge cores

API Integration

This command uses the Knowledge API with the delete-kg-core operation to permanently remove knowledge cores.

Use Cases

Development Cleanup

# Remove test knowledge cores
tg-delete-kg-core --id "test-data-v1" -U developer
tg-delete-kg-core --id "experimental-core" -U developer

Version Management

# Remove obsolete versions after upgrading
tg-get-kg-core --id "knowledge-v1" -o backup-v1.msgpack
tg-delete-kg-core --id "knowledge-v1"
# Keep only knowledge-v2

Storage Cleanup

# Clean up unused knowledge cores
for core in $(tg-show-kg-cores | grep "temp-"); do
    echo "Deleting temporary core: $core"
    tg-delete-kg-core --id "$core"
done

Error Recovery

# Remove corrupted knowledge cores
tg-delete-kg-core --id "corrupted-core-2024"
tg-put-kg-core --id "restored-core-2024" -i restored-backup.msgpack

Safe Deletion Workflow

Standard Procedure

# 1. Backup the knowledge core
tg-get-kg-core --id "target-core" -o "backup-$(date +%Y%m%d).msgpack"

# 2. Unload from active flows
tg-unload-kg-core --id "target-core" --flow-id "production-flow"

# 3. Verify no dependencies
tg-show-config | grep "target-core"

# 4. Perform deletion
tg-delete-kg-core --id "target-core"

# 5. Verify deletion
tg-show-kg-cores | grep "target-core"

Bulk Deletion

# Delete multiple cores safely
cores_to_delete=("old-core-1" "old-core-2" "test-core")

for core in "${cores_to_delete[@]}"; do
    echo "Processing $core..."
    
    # Backup
    tg-get-kg-core --id "$core" -o "backup-$core-$(date +%Y%m%d).msgpack"
    
    # Delete
    tg-delete-kg-core --id "$core"
    
    # Verify
    if tg-show-kg-cores | grep -q "$core"; then
        echo "ERROR: $core still exists after deletion"
    else
        echo "SUCCESS: $core deleted"
    fi
done

Best Practices

1. Always Backup: Export knowledge cores before deletion
2. Check Dependencies: Verify no flows are using the core
3. Staged Deletion: Delete test/development cores before production
4. Verification: Confirm deletion completed successfully
5. Documentation: Record why cores were deleted for audit purposes
6. Access Control: Ensure only authorized users can delete cores

Recovery Options

If Accidentally Deleted

# Restore from backup if available
tg-put-kg-core --id "restored-core" -i backup.msgpack

# Reload into flows if needed
tg-load-kg-core --id "restored-core" --flow-id "production-flow"

Audit Trail

# Keep records of deletions
echo "$(date): Deleted knowledge core 'old-core' - reason: obsolete version" >> deletion-log.txt

System Impact

Storage Recovery

• Disk space is freed immediately
• Database indexes are updated
• System performance may improve

Service Continuity

• Running flows continue to operate
• Other knowledge cores remain unaffected
• New knowledge cores can use the same ID

Troubleshooting

Deletion Fails

# Check if core is loaded in flows
tg-show-flows | grep -A 10 "knowledge"

# Force unload if necessary
tg-unload-kg-core --id "stuck-core" --flow-id "problem-flow"

# Retry deletion
tg-delete-kg-core --id "stuck-core"

Partial Deletion

# If core still appears in listings
tg-show-kg-cores | grep "partially-deleted"

# Contact system administrator if deletion appears incomplete