Import and export

Import items [[dynamodb.import]]

Writes items into a table from inline data, a local file, an S3 object or another DynamoDB table. It checks the full source first. Sometimes destructive

[[dynamodb.import]]
name = "Load seed orders"
tableArn = "arn:aws:dynamodb:ap-southeast-2:123456789012:table/Orders-dev"
conflictMode = "skip-existing"
source = { type = "file", path = "seed/orders.jsonl" }

# Items written in the request
source = { type = "inline", items = [{ accountId = "account#1", orderId = "order#1001" }] }

# An object in S3
source = { type = "s3", bucket = "commerce-seed-data", key = "orders/seed.csv", region = "ap-southeast-2", format = "csv" }

# Another DynamoDB table, optionally in another account
source = { type = "dynamodb-table", tableArn = "arn:aws:dynamodb:ap-southeast-2:111122223333:table/Orders", profileName = "commerce-prod" }

• A JSON file has an array of items. Items can be plain or typed.
• Dynomate imports CSV cells as strings, leaves out empty cells, and adds the warning csv-values-imported-as-strings.
• Before it writes, Dynomate checks that each item parses, has the destination keys with the correct types, and has a unique key.
• If a check fails, the operation fails with DNML_IMPORT_PREFLIGHT and writes nothing.
• The import is destructive if conflictMode is "overwrite".
• The result has importedCount, skippedCount, failedCount, totalItems and warnings.

Keys

source map Required

Where the items come from: "inline" items, a local "file", an "s3" object or another "dynamodb-table". Files can be JSON, JSON Lines or CSV, and Dynomate imports CSV values as strings. In the app: Source tab › Import source

conflictMode enum: "overwrite" | "skip-existing"

What Dynomate does when an item with the same key exists: "overwrite", the default, replaces it, and "skip-existing" keeps it. In the app: Source tab › Existing items

chunkSize integer

Items in each write call, from 1 to 25. The default is 25. In the app: Execution tab › Items per write

concurrency integer

The number of parallel write calls. The default is 8. In the app: Execution tab › Write concurrency

continueOnItemError boolean

If true, Dynomate counts failed items, and the import succeeds if it writes at least one item. The default is false. In the app: Execution tab › Continue after item errors

Export items [[dynamodb.export]]

Scans a table and writes its items to a local file in JSON, JSON Lines, CSV or DynamoDB JSON Lines format.

[[dynamodb.export]]
name = "Export orders"
tableArn = "arn:aws:dynamodb:ap-southeast-2:123456789012:table/Orders"
snapshot = true
target = { type = "file", path = "exports/", format = "dynamodb-jsonl" }

• path can be:
  • A file. If the file exists, the export fails and does not overwrite it.
  • A directory. Dynomate makes a file name from the table name.
  • Not set. Dynomate writes to the exports folder in the app data directory.
• dynamodb-jsonl keeps all DynamoDB types. Other formats write plain values: a set becomes a list, and binary becomes base64 text.
• CSV has one column for each top-level attribute name, in sorted order. Nested values become JSON text.
• An S3 target, type = "s3", is not supported and fails with DNML_UNSUPPORTED_OPERATION.
• The app and the CLI share snapshots if they use the same app data directory. See Local SQL.
• If the snapshot registration fails, the operation fails, but its result still has outputPath.
• The result has outputPath, format, exportedCount, outputSizeBytes, segmentCount and, with snapshot = true, snapshotId.

A later import can read the export file:

source = { type = "file", path = "${export_orders.outputPath}", format = "jsonl" }

For a full example, see import-export.

Keys

target map Required

Where Dynomate writes the items: type "file", a path to a file or directory, and a format. The format is "jsonl-gzip", the default, or "jsonl", "json", "csv" or "dynamodb-jsonl". In the app: Output tab › Export target

segments integer

The number of parallel scan segments. By default, Dynomate sets it. In the app: Execution tab › Scan segments

scanLimit integer

Items in each scan page. The default is 1,000. In the app: Execution tab › Scan page size

filterExpression string

If set, Dynomate exports only the items that match. In the app: Scope tab › Filter expression

projectionExpression string

Sets the attributes that Dynomate writes for each item. In the app: Output tab › Projection expression

expressionAttributeNames map

Maps the #name placeholders in expressions to attribute names. In the app: Scope tab › Attribute name aliases

expressionAttributeValues map

Maps the :value placeholders in expressions to values, in plain or typed form. In the app: Scope tab › Attribute value aliases

snapshot boolean

If true, Dynomate also registers the export as a local snapshot that you can query, and returns its ID. The default is false. In the app: Output tab › Register as queryable snapshot