mirror of https://github.com/apache/druid.git
58 lines
2.0 KiB
Markdown
58 lines
2.0 KiB
Markdown
---
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layout: doc_page
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title: "Data Source Metadata Queries"
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---
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# Data Source Metadata Queries
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Data Source Metadata queries return metadata information for a dataSource. These queries return information about:
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* The timestamp of latest ingested event for the dataSource. This is the ingested event without any consideration of rollup.
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The grammar for these queries is:
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```json
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{
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"queryType" : "dataSourceMetadata",
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"dataSource": "sample_datasource"
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}
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```
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There are 2 main parts to a Data Source Metadata query:
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|property|description|required?|
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|--------|-----------|---------|
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|queryType|This String should always be "dataSourceMetadata"; this is the first thing Apache Druid (incubating) looks at to figure out how to interpret the query|yes|
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|dataSource|A String or Object defining the data source to query, very similar to a table in a relational database. See [DataSource](../querying/datasource.html) for more information.|yes|
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|context|See [Context](../querying/query-context.html)|no|
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The format of the result is:
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```json
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[ {
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"timestamp" : "2013-05-09T18:24:00.000Z",
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"result" : {
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"maxIngestedEventTime" : "2013-05-09T18:24:09.007Z"
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}
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} ]
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```
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