Dynamodb - Revision history

Jfreier at 18:17, 5 January 2023

2023-01-05T18:17:47Z

Jfreier at 18:15, 5 January 2023

2023-01-05T18:15:15Z

Jfreier at 18:14, 5 January 2023

2023-01-05T18:14:22Z

Jfreier at 18:10, 5 January 2023

2023-01-05T18:10:22Z

Jfreier at 18:07, 5 January 2023

2023-01-05T18:07:38Z

Jfreier at 18:03, 5 January 2023

2023-01-05T18:03:59Z

Jfreier at 17:58, 5 January 2023

2023-01-05T17:58:59Z

Jfreier at 17:58, 5 January 2023

2023-01-05T17:58:14Z

Jfreier: Created page with "DynamoDB is an AWS product that has a stand alone app for development but is really suppose to be built out in AWS where they handle the administration/OPS. This is a NoSQL d..."

2023-01-05T15:29:23Z

Created page with "DynamoDB is an AWS product that has a stand alone app for development but is really suppose to be built out in AWS where they handle the administration/OPS. This is a NoSQL d..."

New page

DynamoDB is an AWS product that has a stand alone app for development but is really suppose to be built out in AWS where they handle the administration/OPS.

This is a NoSQL database.

@@ Line 17: / Line 17: @@
 There are two types of keys that can be used to define a primary key.
-Partition keys are the how the database separates data in the backend.
+Partition keys are the how the database separates data in the backend.  There are used to optimize queries.
 Sort keys allow you to sort data by a secondary column.

← Older revision		Revision as of 18:15, 5 January 2023
Line 22:		Line 22:

	If more sorting is required, take a look at using Local Global Index.		If more sorting is required, take a look at using Local Global Index.
		+
		+	When adding data, which ever is setup...These fields will be required, all other data is optional.

	== Global Secondary Index ==		== Global Secondary Index ==

← Older revision		Revision as of 18:14, 5 January 2023
Line 175:		Line 175:
	}		}
	});		});
		+
		+
		+	== Get a record ==
		+	var params = {
		+	TableName: table,
		+	Key: {
		+	"id": id
		+	}
		+	};
		+	try {
		+	const results = await docClient.get(params).promise();
		+	console.log('Find by id ' + id, JSON.stringify(results, null, 2));
		+	return results;
		+	} catch (err) {
		+	console.log(err);
		+	throw err;
		+	};
		+
		+
		+	== Add a record ==
		+	var params = {
		+	TableName: table,
		+	Item: entity
		+	};
		+	try {
		+	const results = await docClient.put(params).promise();
		+	console.log('Added ', entity);
		+	return entity;
		+	} catch (err) {
		+	console.log(err);
		+	throw err;
		+	};
		+
		+
		+	== Delete a record ==
		+	var params = {
		+	TableName: table,
		+	Key: {
		+	id: id
		+	}
		+	};
		+	try {
		+	const results = await docClient.delete(params).promise();
		+	console.log('Removed ' + id + " from " + table);
		+	return results;
		+	} catch (err) {
		+	console.log(err);
		+	throw err;
		+	};

← Older revision		Revision as of 18:10, 5 January 2023
Line 2:		Line 2:

	This is a NoSQL database.		This is a NoSQL database.
		+
		+	== DynamoDB Local ==
		+	Amazon has a local version of the DynamoDB that can be downloaded and ran, for development purposes.
		+
		+	1. Download the dynamodb_local_latest.tar.gz
		+	2. Extract
		+	3. Run
		+	java -Djava.library.path=./DynamoDBLocal_lib -jar DynamoDBLocal.jar -sharedDb
		+
		+	When ran a file gets created that holds the data. If deleted...data lost.
		+	shared-local-instance.db

	== Partition Key and Sort Key ==		== Partition Key and Sort Key ==

@@ Line 12: / Line 12: @@
 If more sorting is required, take a look at using Local Global Index.
-== Secondary Global Index ==
+== Global Secondary Index ==
 This allows you to create a super table from the base table, to allow for different keys and sorting when using the `query` command.
@@ Line 99: / Line 99: @@
-== Local Global Index ==
+== Local Secondary Index ==
-Local global index, creates a super table on top of the base table to allow for more sorting abilities.
+This creates a super table on top of the base table to allow for more sorting abilities only.

@@ Line 24: / Line 24: @@
    var params = {
        TableName: "statements",
-       AttributeDefinitions: [{
+       AttributeDefinitions: [{     // Attributes are the items that are used in the key definitions and GSI/LSI.
                AttributeName: "id",
-               AttributeType: "S"
+               AttributeType: "S"   // S - String
            },
+           {
                AttributeName: "time",
-               AttributeType: "N"
+               AttributeType: "N"   // N - Number
            },
+           {
@@ Line 58: / Line 58: @@
            ],
            Projection: {
-               ProjectionType: 'ALL'
+               ProjectionType: 'ALL'    // KEY_ONLY, INCLUDE, ALL - This holds the columns that are used in the GSI and returned when queried.
            },
            ProvisionedThroughput: {
@@ Line 81: / Line 81: @@
 Example query
      this.findLatest = async function(table, userId) {
          var params = {
              TableName: table,
-             IndexName: 'statement_user_index',
+             IndexName: 'statement_user_index',     // Must have the indexName too query against an GSI index.
-             KeyConditionExpression: 'userId = :userId',
+             KeyConditionExpression: 'userId = :userId',   // Must contain the key
-             ExpressionAttributeValues: { ':userId': userId },
+             ExpressionAttributeValues: { ':userId': userId },  // Used like prepared statements.
-             Limit: 1,
+             Limit: 1,  // Number of results returned (optional)
-             ScanIndexForward: false
+             ScanIndexForward: false  // Ascending or Descending. (Optional)
          };
          try {
              const results = await docClient.query(params).promise();
              return results.Items;
          } catch (err) {

← Older revision		Revision as of 17:58, 5 January 2023
Line 2:		Line 2:

	This is a NoSQL database.		This is a NoSQL database.
		+
		+	== Partition Key and Sort Key ==
		+	There are two types of keys that can be used to define a primary key.
		+
		+	Partition keys are the how the database separates data in the backend.
		+
		+	Sort keys allow you to sort data by a secondary column.
		+
		+	If more sorting is required, take a look at using Local Global Index.
		+
		+	== Secondary Global Index ==
		+	This allows you to create a super table from the base table, to allow for different keys and sorting when using the `query` command.
		+
		+	Example
		+	var AWS = require("aws-sdk");
		+	AWS.config.update({
		+	region: "local",
		+	endpoint: "http://localhost:8000"
		+	});
		+	var dynamodb = new AWS.DynamoDB();
		+	var params = {
		+	TableName: "statements",
		+	AttributeDefinitions: [{
		+	AttributeName: "id",
		+	AttributeType: "S"
		+	},
		+	{
		+	AttributeName: "time",
		+	AttributeType: "N"
		+	},
		+	{
		+	AttributeName: "userId",
		+	AttributeType: "S"
		+	}
		+	],
		+	KeySchema: [{
		+	AttributeName: "id",
		+	KeyType: "HASH"
		+	}, //Partition key
		+	{
		+	AttributeName: "userId",
		+	KeyType: "RANGE"
		+	}, //Sort key
		+	],
		+	GlobalSecondaryIndexes: [{
		+	IndexName: 'statement_user_index',
		+	KeySchema: [{
		+	AttributeName: 'userId',
		+	KeyType: 'HASH',
		+	},
		+	{
		+	AttributeName: 'time',
		+	KeyType: 'RANGE',
		+	}
		+	],
		+	Projection: {
		+	ProjectionType: 'ALL'
		+	},
		+	ProvisionedThroughput: {
		+	WriteCapacityUnits: 5,
		+	ReadCapacityUnits: 5
		+	}
		+	}],
		+	ProvisionedThroughput: {
		+	ReadCapacityUnits: 5,
		+	WriteCapacityUnits: 5
		+	}
		+	};
		+	dynamodb.createTable(params, function(err, data) {
		+	if (err) {
		+	console.error("Unable to create table. Error JSON:", JSON.stringify(err, null, 2));
		+	} else {
		+	console.log("Created table. Table description JSON:", JSON.stringify(data, null, 2));
		+	}
		+	});
		+
		+
		+	== Local Global Index ==
		+	Local global index, creates a super table on top of the base table to allow for more sorting abilities.