mirror of https://github.com/apache/druid.git
61 lines
2.1 KiB
Markdown
61 lines
2.1 KiB
Markdown
---
|
|
id: datasourcemetadataquery
|
|
title: "DatasourceMetadata queries"
|
|
sidebar_label: "DatasourceMetadata"
|
|
---
|
|
|
|
<!--
|
|
~ Licensed to the Apache Software Foundation (ASF) under one
|
|
~ or more contributor license agreements. See the NOTICE file
|
|
~ distributed with this work for additional information
|
|
~ regarding copyright ownership. The ASF licenses this file
|
|
~ to you under the Apache License, Version 2.0 (the
|
|
~ "License"); you may not use this file except in compliance
|
|
~ with the License. You may obtain a copy of the License at
|
|
~
|
|
~ http://www.apache.org/licenses/LICENSE-2.0
|
|
~
|
|
~ Unless required by applicable law or agreed to in writing,
|
|
~ software distributed under the License is distributed on an
|
|
~ "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
|
|
~ KIND, either express or implied. See the License for the
|
|
~ specific language governing permissions and limitations
|
|
~ under the License.
|
|
-->
|
|
|
|
> Apache Druid supports two query languages: [Druid SQL](sql.md) and [native queries](querying.md).
|
|
> This document describes a query
|
|
> type that is only available in the native language.
|
|
|
|
Data Source Metadata queries return metadata information for a dataSource. These queries return information about:
|
|
|
|
* The timestamp of latest ingested event for the dataSource. This is the ingested event without any consideration of rollup.
|
|
|
|
The grammar for these queries is:
|
|
|
|
```json
|
|
{
|
|
"queryType" : "dataSourceMetadata",
|
|
"dataSource": "sample_datasource"
|
|
}
|
|
```
|
|
|
|
There are 2 main parts to a Data Source Metadata query:
|
|
|
|
|property|description|required?|
|
|
|--------|-----------|---------|
|
|
|queryType|This String should always be "dataSourceMetadata"; this is the first thing Apache Druid looks at to figure out how to interpret the query|yes|
|
|
|dataSource|A String or Object defining the data source to query, very similar to a table in a relational database. See [DataSource](../querying/datasource.md) for more information.|yes|
|
|
|context|See [Context](../querying/query-context.md)|no|
|
|
|
|
The format of the result is:
|
|
|
|
```json
|
|
[ {
|
|
"timestamp" : "2013-05-09T18:24:00.000Z",
|
|
"result" : {
|
|
"maxIngestedEventTime" : "2013-05-09T18:24:09.007Z"
|
|
}
|
|
} ]
|
|
```
|