Autosave: 2024-06-23 13:00:03

zk/Database_options_on_AWS.md

@@ -2,6 +2,7 @@
 tags:
   - AWS
   - databases
+  - dynamodb
 ---
 
 # Database options

zk/DynamoDB SDK commands.md

@@ -21,11 +21,41 @@ const client = new DynamoDBClient({
 });
 ```
 
+### DynamoDB Document Client
+
+The Document Client returns the data as a standard JSON document in the manner
+of a document-based NoSQL database. Without it, DynamoDB will return the data
+with type data which is unwieldy and hard to parse.
+
+To transform into a document structure:
+
+```js
+import DynamoDBClient from "@aws-sdk/client-dynamodb";
+import DynamoDBDocumentClient from "@aws-sdk/lib-dynamodb";
+
+const client = new DynamoDBClient({
+  region: "eu-west-2",
+  accessKeyId: process.env.ACCESS_KEY_ID,
+  secretAccessKey: process.env.ACCESS_KEY_ID,
+});
+
+const dynamoDbDocumentClient = DynamoDBDocumentClient.from(client);
+```
+
 ## Query a table
 
 Querying is the most performant and cost-effective method since it is an O(1)
 lookup against a partition key or secondary index.
 
+```js
+const params = {
+  TableName: "YourTableName",
+  KeyConditionExpression: "#pk = :pk",
+  ExpressionAttributeNames: { "#pk": "PrimaryKeyAttributeName" },
+  ExpressionAttributeValues: { ":pk": "PrimaryKeyValue" },
+};
+```
+
 ## Scan a table
 
 Scanning is less performant (O(n)) and most expensive since it requires checking