API Parity

API Parity

Overview

DynamoDbLite implements the IAmazonDynamoDB interface from AWSSDK.DynamoDBv2. This page documents which operations are supported, partially supported, stubbed, or not implemented, and highlights behavioral differences from real DynamoDB.

Operation Support Matrix

Table Management

Operation	Status	Notes
CreateTableAsync	Supported	Immediate ACTIVE status
DeleteTableAsync	Supported	Synchronous deletion
DescribeTableAsync	Supported	Exact item count and size
ListTablesAsync	Supported	All overloads
UpdateTableAsync	Partial	GSI create/delete; throughput changes accepted but no-op

Item CRUD

Operation	Status	Notes
PutItemAsync	Supported	ConditionExpression, ReturnValues (ALL_OLD)
GetItemAsync	Supported	ProjectionExpression, ConsistentRead (no-op)
DeleteItemAsync	Supported	ConditionExpression, ReturnValues (ALL_OLD)
UpdateItemAsync	Supported	All UpdateExpression clauses, all ReturnValues modes

Query & Scan

Operation	Status	Notes
QueryAsync	Supported	KeyConditionExpression, FilterExpression, pagination, index queries
ScanAsync	Supported	FilterExpression, pagination, index scans, legacy overloads

Batch Operations

Operation	Status	Notes
BatchGetItemAsync	Supported	Multi-table, ProjectionExpression per table
BatchWriteItemAsync	Supported	Mixed put/delete, duplicate detection
BatchExecuteStatementAsync	Not Implemented	Throws NotImplementedException

Transactions

Operation	Status	Notes
TransactWriteItemsAsync	Supported	All action types, idempotency tokens
TransactGetItemsAsync	Supported	Multi-table, ProjectionExpression

Secondary Indexes

Feature	Status	Notes
GSI at table creation	Supported	Up to 5
LSI at table creation	Supported	Up to 5
GSI via UpdateTable	Supported	With immediate backfill
GSI deletion	Supported
Projection types (ALL, KEYS_ONLY, INCLUDE)	Supported
Sparse indexes	Supported
ConsistentRead on GSI	Supported	Throws exception (matches DynamoDB)

TTL

Operation	Status	Notes
UpdateTimeToLiveAsync	Supported	Enable/disable with backfill
DescribeTimeToLiveAsync	Supported

Tags

Operation	Status	Notes
TagResourceAsync	Supported
UntagResourceAsync	Supported
ListTagsOfResourceAsync	Supported

Admin / Endpoints

Operation	Status	Notes
DescribeEndpointsAsync	Stubbed	Returns dynamodb.localhost
DescribeLimitsAsync	Stubbed	Returns hardcoded values (80K/40K)
DetermineServiceOperationEndpoint	Stubbed	Returns http://dynamodb.localhost

Export & Import

Operation	Status	Notes
ExportTableToPointInTimeAsync	Supported	Local filesystem, DYNAMODB_JSON only
DescribeExportAsync	Supported
ListExportsAsync	Supported
ImportTableAsync	Supported	Local filesystem, DYNAMODB_JSON only
DescribeImportAsync	Supported
ListImportsAsync	Supported

Backup & Restore (Not Implemented)

All throw NotImplementedException:

• CreateBackupAsync
• DeleteBackupAsync
• DescribeBackupAsync
• DescribeContinuousBackupsAsync
• ListBackupsAsync
• RestoreTableFromBackupAsync
• RestoreTableToPointInTimeAsync
• UpdateContinuousBackupsAsync

Global Tables (Not Implemented)

All throw NotImplementedException:

• CreateGlobalTableAsync
• DescribeGlobalTableAsync
• DescribeGlobalTableSettingsAsync
• DescribeTableReplicaAutoScalingAsync
• ListGlobalTablesAsync
• UpdateGlobalTableAsync
• UpdateGlobalTableSettingsAsync
• UpdateTableReplicaAutoScalingAsync

Kinesis Streams (Not Implemented)

All throw NotImplementedException:

• DescribeKinesisStreamingDestinationAsync
• DisableKinesisStreamingDestinationAsync
• EnableKinesisStreamingDestinationAsync
• UpdateKinesisStreamingDestinationAsync

PartiQL (Not Supported)

• ExecuteStatementAsync — throws NotSupportedException
• ExecuteTransactionAsync — throws NotSupportedException

Other (Not Implemented)

All throw NotImplementedException:

• DeleteResourcePolicyAsync
• GetResourcePolicyAsync
• PutResourcePolicyAsync
• DescribeContributorInsightsAsync
• ListContributorInsightsAsync
• UpdateContributorInsightsAsync

Behavioral Differences

Behavior	DynamoDB	DynamoDbLite
Table status transitions	CREATING → ACTIVE → DELETING	Immediately ACTIVE; synchronous deletion
GSI creation	CREATING status, eventual backfill	Synchronous backfill, immediately ACTIVE
Provisioned throughput	Enforced; throttling on exceeded capacity	Stored but not enforced; no throttling
Consumed capacity	Tracked and returned	Not tracked
ConsistentRead	Eventually vs strongly consistent	All reads are strongly consistent (SQLite)
TTL deletion	Items deleted ~48 hours after expiry; may still appear in reads	Items filtered instantly at read time; physically deleted within 30s
TTL enable/disable	Can take up to 1 hour	Immediate
Item count / table size	Updated approximately every 6 hours	Updated on every write (exact)
Table ARN	Region-specific, real account ID	arn:aws:dynamodb:local:000000000000:table/{name}
Export/Import	S3-based	Local filesystem
Export format	DYNAMODB_JSON and ION	DYNAMODB_JSON only
Parallel scan	Supports segments for parallelism	Not supported (TotalSegments/Segment ignored)
Idempotency token	Persisted server-side	In-memory cache with 10-minute TTL
UnprocessedKeys/Items	May return unprocessed items under throttling	Always empty (all items processed)
Auto-scaling	Adjusts throughput based on load	Not applicable
Encryption	At-rest and in-transit encryption	Not applicable (local storage)
Point-in-time recovery	Continuous backups	Not implemented
DynamoDB Streams	Change data capture	Not implemented
Global tables	Multi-region replication	Not implemented

Known Limitations

• No parallel scan — TotalSegments and Segment parameters are ignored
• No capacity tracking — ReturnConsumedCapacity has no effect
• No DynamoDB Streams — no change event notifications
• No auto-scaling — throughput values are decorative
• Export format — only DYNAMODB_JSON (ION not supported)
• Connection strings — must follow Microsoft.Data.Sqlite format
• Paginators — IDynamoDBv2PaginatorFactory is not implemented (returns null)