Overview of the NoSQL Web API
Introduction
The platform's NoSQL Web API provides access to the NoSQL database service, which enables storing and consuming data in a tabular format. For more information, see Working with NoSQL Data. The platform's unified data model enables you to use the NoSQL Web API to fetch and update any object in the system.
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To add an item to a table or replace an existing item, use
PutItem .To create a table, just begin adding items. The table will be created automatically with the first item that you add. See Working with NoSQL Data.
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To update an existing item in a table, use
UpdateItem . . -
To retrieve attributes of a table item, use
GetItem . -
To retrieve attributes of multiple items in a table or in a data container's root directory, use
GetItems .GetItems supports scan optimizations either by performing range scans that use the items' sharding and sorting keys to locate items more quickly, or by dividing the table-scan operation into multiple segments that can be assigned to different workers for implementing a parallel scan. See Scan Optimization in theGetItems documentation. -
To delete a table, either delete (remove) the table directory by using a file-system command, or use the
delete client method of the V3IO Frames NoSQL backend. See Working with NoSQL Data.
In the NoSQL Web API, an attribute is represented by an
The NoSQL Web API is part of the data-service web APIs and conforms to the related structure and syntax rules — see Data-Service Web-API General Structure.
Item Name and Primary Key
A table item is a data object, and as such needs to be assigned a unique primary-key value, which serves as the item's name and is stored by the platform in the
Table Schema
The NoSQL Web API doesn't enforce a specific table schema: i.e., the items don't all need to contain the same attributes and items can have different data types for the same attribute. However, be advised that if the table items don't follow a consistent attributes schema you might fail to read data from the table using a structured-data interface such as Spark Datasets, Presto, and V3IO Frames.