Query Parameters Overview (OLAP)

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OLAP Object Queries: Query Parameters Overview

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An OLAP object query allows the following parameters:

• Query (required): A DQL query expression that selects objects in the perspective table.
• Page size (optional): Limits the number of objects returned. If absent, the page size defaults to search_default_page_size in the doradus.yaml file. The page size can be set to 0 to disable paging, causing all results to be returned in a single page.
• Fields (optional): A comma-separated list of fields to return for each object. Several formats and options are allowed for this parameter as described later in the section Fields Parameter. By default, all scalar fields for selected objects are returned.
• Metrics (optional): A comma-separated list of metric expressions to be computed for each object. This parameter essentially extends the fields parameter with additional computed values. See the section Metric Parameter for more information.
• Order (optional): Orders the objects returned by one or more fields. Without this parameter, objects are returned in an internally-defined order. When a single order field is specified, by default objects are sorted in ascending order of the field’s value. Optionally, the field name can be followed by ASC to explicitly request ascending order or DESC to request descending order. Multiple order fields can be specified to sort objects by primary values followed by secondary values. See the section Order Parameter for more information.
• Skip (optional): Causes the specified number of objects to be skipped. Without this parameter, the first page of objects is returned.
• Continuation (optional): Causes a secondary set of objects to be returned. There are two forms for this parameter, which can only be used with unsorted queries.
• Shards (this or Range is required): Specifies a list of shards to be searched by the query.
• Range (this or Shards is required): Specifies a range of shards to be searched by the query.

How query parameters are passed depends on the REST command. OLAP supports object queries submitted in two different ways:

• URI command: All query parameters are passed in the URI of the command.
• Entity command: All query parameters are passed in an input entity (XML or JSON document) submitted with the command.

REST commands and how query parameters are passed are described in the section OLAP REST Commands. The examples in this section use the URI command format.