What represents multiple related request items grouped together as one request
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I believe that another correct way to approach this would be to create another resource that represents your collection of resources. Example, imagine that we have an endpoint like Show
Now, if we want to support bulk creation, we should consider a new flock resource at Resources are a higher level representation, unrelated with your data. Operating on a resource can have significant side effects, like firing an alert to a user, updating other related data, initiating a long lived process, etc. For example, we could map a file system or even the unix I think it is safe to assume that operating a resource may also mean to create several other entities as a side effect. In Amazon DynamoDB, an item is a collection of attributes. Each attribute has a name and a value. An attribute value can be a scalar, a set, or a document type. For more information, see Amazon DynamoDB: How it works. DynamoDB provides four operations for basic create, read, update, and delete (CRUD) functionality. All these operations are atomic.
Each of these operations requires that you specify the primary key of the item that you want to work with. For example, to read an item using In addition to the four basic CRUD operations, DynamoDB also provides the following:
These batch operations combine multiple CRUD operations into a single request. In addition, the batch operations read and write items in parallel to minimize response latencies. This section describes how to use these operations and includes related topics, such as conditional updates and atomic counters. This section also includes example code that uses the AWS SDKs. Reading an itemTo read an item from a DynamoDB table, use the Example The following AWS CLI example shows how to read an item from the With A To return the number of read capacity units consumed by Example The following AWS Command Line Interface (AWS CLI) example shows some of the optional Writing an itemTo create, update, or delete an item in a DynamoDB table, use one of the following operations:
For each of these operations, you must specify the entire primary key, not just part of it. For example, if a table has a composite primary key (partition key and sort key), you must provide a value for the partition key and a value for the sort key. To return the number of write capacity units consumed by any of these operations, set the
PutItemExample Write a new item to the The arguments for If an item with the specified key does not exist, You use an update expression to specify the attributes that you want to modify and their new values. For more information, see Update expressions. Within the update expression, you use expression attribute values as placeholders for the actual values. For more information, see Expression attribute values. Example Modify various attributes in the The arguments for The arguments for DeleteItemExample The following AWS CLI example shows how to delete the Return valuesIn some cases, you might want DynamoDB to return certain attribute values as they appeared before or after you modified them. The The default value for The following are the other valid settings for PutItem
The most common usage for
DeleteItem
Batch operationsFor applications that need to read or write multiple items, DynamoDB provides the The batch operations are essentially wrappers around multiple read or write requests. For example, if a In general, a batch operation does not fail unless all the requests in the batch fail. For example, suppose that you perform a BatchGetItemA single Example Retrieve two items from the The arguments for BatchWriteItemThe Example Write two items to the The arguments for Atomic countersYou can use the You might use an atomic counter to track the number of visitors to a website. In this case, your application would increment a numeric value, regardless of its current value. If an An atomic counter would not be appropriate where overcounting or undercounting can't be tolerated (for example, in a banking application). In this case, it is safer to use a conditional update instead of an atomic counter. For more information, see Incrementing and decrementing numeric attributes. Example The following AWS CLI example increments the By default, the DynamoDB write operations ( DynamoDB optionally supports conditional writes for these operations. A conditional write succeeds only if the item attributes meet one or more expected conditions. Otherwise, it returns an error. Conditional writes are helpful in many situations. For example, you might want a Conditional writes are helpful in cases where multiple users attempt to modify the same item. Consider the following diagram, in which two users (Alice and Bob) are working with the same item from a DynamoDB table.  Suppose that Alice uses the AWS CLI to update the The arguments for Now suppose that Bob issues a similar Bob's request succeeds, but Alice's earlier update is lost. To request a conditional Now consider the following diagram, showing how conditional writes would prevent Alice's update from being overwritten. Alice first tries to update The arguments for Alice's update succeeds because the condition evaluates to true. Next, Bob attempts to update the Because Alice has previously changed the For more information, see Condition expressions. Conditional write idempotenceConditional writes can be idempotent if the conditional check is on the same attribute that is being updated. This means that DynamoDB performs a given write request only if certain attribute values in the item match what you expect them to be at the time of the request. For example, suppose that you issue an Capacity units consumed by conditional writesIf a
Write operations consume write capacity units only. They never consume read capacity units. A failed conditional write returns a To return the number of write capacity units consumed during a conditional write, you use the
Unlike a global secondary index, a local secondary index shares its provisioned throughput capacity with its table. Read and write activity on a local secondary index consumes provisioned throughput capacity from the table. What represents multiple related request items grouped together as one?An order guide represents multiple related request items grouped together as one request.
What is the difference between order guide and catalog item in ServiceNow?2. The main difference between a catalog item and an order guide is what happens after you submit them. A catalog item works with the cart where you can add multiple and then checkout. On the back end it creates a request, request item, and possibly approvals and tasks depending on its workflow.
What is an order guide?An order guide submits a single service catalog request that generates several items. Order guides allow you to define rules that identify which catalog items to include in a request. This can be extremely useful in the (obvious) use case of user onboarding.
What is the difference between service catalog and record producer in ServiceNow?The service catalog is a collection of request forms presented as Catalog Items, Record Prodcures, Content Items, Order Guides, etc. A record producer is a nice front end you can include in your Service Catalog to create records. Ask user friendly questions instead of using field labels on a standard form.
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