devo dynamodb¶

DynamoDB table management and data export utilities.

Synopsis¶

devo dynamodb <command> [OPTIONS]

Description¶

Provides utilities for working with AWS DynamoDB tables, including listing tables, describing table schemas, and exporting table data to various formats (CSV, JSON, JSONL, TSV) with advanced filtering and optimization.

Commands¶

list¶

List all DynamoDB tables in the region.

devo dynamodb list [OPTIONS]

Options:

• -r, --region TEXT - AWS region (default: us-east-1)

Examples:

# List tables in default region
devo dynamodb list

# List tables in specific region
devo dynamodb list --region us-west-2

# With specific profile
devo --profile production dynamodb list

describe¶

Show detailed information about a table.

devo dynamodb describe TABLE_NAME [OPTIONS]

Options:

• -r, --region TEXT - AWS region (default: us-east-1)

Examples:

# Describe table
devo dynamodb describe users-table

# Describe in specific region
devo dynamodb describe orders-prod --region us-east-1

Output includes:

• Table name and ARN
• Primary key schema
• Global and Local Secondary Indexes
• Item count and table size
• Provisioned/On-Demand capacity
• Stream settings
• Encryption settings

export¶

Export DynamoDB table to CSV, JSON, or JSONL format.

devo dynamodb export TABLE_NAME [OPTIONS]

Basic Options¶

Filtering Options¶

Export Modes¶

Export Modes:

• strings - Serialize complex types as JSON strings
• flatten - Flatten nested objects (e.g., address.city)
• normalize - Expand lists to multiple rows

CSV Options¶

Boolean Formats:

• lowercase - true/false
• uppercase - True/False
• numeric - 1/0
• letter - t/f

JSON Options¶

Performance Options¶

Template Options¶

Other Options¶

list-templates¶

List all saved export templates.

devo dynamodb list-templates

Shows all templates saved with --save-template.

Examples¶

Basic Export¶

# Export entire table to CSV
devo dynamodb export my-table

# Export to JSON
devo dynamodb export my-table -f json

# Export to specific file
devo dynamodb export my-table -o data/users.csv

# Export with limit
devo dynamodb export my-table -l 1000

Query Optimization¶

The export command automatically optimizes queries:

1. Index Detection: Analyzes filter expression and selects best index
2. Query vs Scan: Uses Query when possible (faster and cheaper)
3. Projection: Only fetches requested attributes
4. Parallel Scan: Optionally splits scan across multiple segments

Example: Automatic Optimization¶

# This filter expression:
devo dynamodb export users --filter "userId = 'user123'"

# Automatically:
# 1. Detects userId is a key in GSI "userId-index"
# 2. Uses Query instead of Scan
# 3. Much faster and cheaper

Configuration¶

Export templates are stored in ~/.devo/config.json:

{
  "dynamodb": {
    "export_templates": {
      "active-users": {
        "table_name": "users",
        "filter_expression": "status = :status",
        "expression_attribute_values": {
          ":status": "active"
        },
        "attributes": ["id", "name", "email"]
      }
    }
  }
}

Performance Tips¶

1. Use filters: Export only needed data
2. Use projections: Specify attributes with -a
3. Use parallel scan: For large tables (>1GB)
4. Use compression: For large exports
5. Use Query: Let auto-optimization detect indexes

Troubleshooting¶

Export is slow¶

# Use parallel scan
devo dynamodb export my-table --parallel-scan --segments 8

Filter not working¶

# Check filter syntax
devo dynamodb export my-table --filter "status = 'active'" --dry-run

# Use manual filter values if needed
devo dynamodb export my-table \
  --filter "status = :st" \
  --filter-values '{":st": {"S": "active"}}'

```bash
# Use expression attribute names
devo dynamodb export my-table \
  --filter "#status = :st" \
  --filter-names '{"#status": "status"}' \
  --filter-values '{":st": {"S": "active"}}'

Exit Codes¶

See Also¶

• DynamoDB Export Guide
• AWS Setup - Configure AWS credentials
• devo config - Manage templates

Notes¶

• Requires AWS credentials with DynamoDB read permissions
• Large exports may take time and consume read capacity
• Use --limit for testing filters
• Templates are stored in ~/.devo/config.json
• Parallel scan is experimental and may not work with all filters