介绍从亚马逊 DynamoDB 向亚马逊 S3 的增量导出

# full export
aws dynamodb export-table-to-point-in-time \
  --table-arn arn:aws:dynamodb:REGION:ACCOUNT:table/TABLENAME \
  --s3-bucket BUCKET --s3-prefix PREFIX \
  --export-time 1693569600

# incremental export, starting at the end time of the full export
aws dynamodb export-table-to-point-in-time \
  --table-arn arn:aws:dynamodb:REGION:ACCOUNT:table/TABLENAME \
  --s3-bucket BUCKET --s3-prefix PREFIX \
  --incremental-export-specification ExportFromTime=1693569600,ExportToTime=1693656000,ExportViewType=NEW_AND_OLD_IMAGES \
  --export-type INCREMENTAL_EXPORT

DestinationBucket/DestinationPrefix
.
└── AWSDynamoDB
  ├── 01693685827463-2d8752fd # the single full export
  │   ├── manifest-files.json # manifest points to files under 'data' subfolder
  │   ├── manifest-files.checksum
  │   ├── manifest-summary.json # stores metadata about request
  │   ├── manifest-summary.md5
  │   ├── data # full exports hold their data files internally
  │   │   ├── 25xwjjhpziyvjb6lcaj2dqinta.json.gz
  │   │   ├── ...
  │   └── _started # empty file for permission check
  ├── 01693685934212-ac809da5 # an incremental export
  │   ├── manifest-files.json # manifest points to files under 'data' outer folder
  │   ├── manifest-files.checksum
  │   ├── manifest-summary.json # stores metadata about request
  │   ├── manifest-summary.md5
  │   └── _started # empty file for permission check
  ├── 01693686034521-ac809da5
  │   ├── manifest-files.json
  │   ├── manifest-files.checksum
  │   ├── manifest-summary.json
  │   ├── manifest-summary.md5
  │   └── _started
  ├── data # single 'data' folder holding all incremental data
  │   ├── sgad6417s6vss4p7owp0471bcq.json.gz
  │ ...

// Ex 1: Insert
//   An insert means the item did not exist before the incremental export window
//   and was added during the incremental export window

{
   "Metadata": {
     "WriteTimestampMicros": "1680109764000000"
   },
   "Key": {
     "PK": { 
       "S": "CUST#100" 
     }
   },
   "NewImage": {
     "PK": { 
       "S": "CUST#100" 
     },
     "FirstName": {
       "S": "John"
     },
     "LastName": {
       "S": "Don"
     }
   }
}

// Ex 2: Update
//   An update means the item existed before the incremental export window
//   and was updated during the incremental export window. 
//   The OldImage would not be present if choosing "New images only".

{
   "Metadata": {
     "WriteTimestampMicros": "1680109764000000"
   },
   "Key": {
     "PK": { 
       "S": "CUST#200" 
     }
   },
   "OldImage": {
     "PK": { 
       "S": "CUST#200" 
     },
     "FirstName": {
       "S": "Mary"
     },
     "LastName": {
       "S": "Grace"
     }
   },
   "NewImage": {
     "PK": { 
       "S": "CUST#200" 
     },
     "FirstName": {
       "S": "Mary"
     },
     "LastName": {
       "S": "Smith"
     }
   }
}

// Ex 3: Delete
//   A delete means the item existed before the incremental export window
//   and was deleted during the incremental export window
//   The OldImage would not be present if choosing "New images only".

{
   "Metadata": {
     "WriteTimestampMicros": "1680109764000000"
   },
   "Key": {
     "PK": { 
       "S": "CUST#300" 
     }
   },
   "OldImage": {
     "PK": { 
       "S": "CUST#300" 
     },
     "FirstName": {
       "S": "Jose"
     },
     "LastName": {
       "S": "Hernandez"
     }
   }
}

// Ex 4: Insert + Delete
//   Nothing is exported if an item is inserted and deleted within the 
//   incremental export window.