Cost Optimization

Since search indexes can contain a large number of items (one item per token per document), optimizing your DynamoDB usage can significantly reduce costs.

Use Short Field Names

Reduce storage costs and RCU/RRU consumption by using short names:

const dynamosearch = new DynamoSearch({
  indexTableName: 'search-index',
  fields: [
    { name: 'title', shortName: 't', analyzer },
    { name: 'description', shortName: 'd', analyzer },
  ],
  keySchema: [{ name: 'id', type: 'HASH' }],
});

Short names are used in the partition key:

• Without: description;machine (19 bytes)
• With: d;machine (9 bytes)

Selective Indexing

Only index fields that need to be searchable:

// ❌ Index everything
const dynamosearch = new DynamoSearch({
  fields: [
    { name: 'title', analyzer },
    { name: 'description', analyzer },
    { name: 'metadata', analyzer }, // Not searchable, wastes space
    { name: 'tags', analyzer },
    { name: 'internalNotes', analyzer }, // Not searchable, wastes space
  ],
});

// ✅ Index only searchable fields
const dynamosearch = new DynamoSearch({
  fields: [
    { name: 'title', analyzer },
    { name: 'description', analyzer },
    { name: 'tags', analyzer },
  ],
});

On-Demand vs Provisioned

On-Demand (default):

await dynamosearch.createIndexTable({
  tableProperties: { BillingMode: 'PAY_PER_REQUEST' },
});

• Pay per request
• Good for unpredictable workloads
• No capacity planning needed

Provisioned:

await dynamosearch.createIndexTable({
  tableProperties: {
    BillingMode: 'PROVISIONED',
    ProvisionedThroughput: {
      ReadCapacityUnits: 5,
      WriteCapacityUnits: 5,
    },
  },
});

• Lower cost for consistent workloads
• Requires capacity planning
• Can use auto-scaling

Monitor Consumed Capacity

Track capacity usage:

const results = await dynamosearch.search('query', {
  fields: ['title', 'description'],
});

console.log('Capacity units consumed:', results.consumedCapacity.capacityUnits);
console.log('Table:', results.consumedCapacity.tableName);

Search Fewer Fields

// More expensive
const results = await dynamosearch.search('query', {
  fields: ['title', 'description', 'tags'],
});

// Less expensive
const results = await dynamosearch.search('query', {
  fields: ['title'],
});