--- layout: doc_page --- # Time Boundary Queries Time boundary queries return the earliest and latest data points of a data set. The grammar is: ```json { "queryType" : "timeBoundary", "dataSource": "sample_datasource" } ``` There are 3 main parts to a time boundary query: |property|description|required?| |--------|-----------|---------| |queryType|This String should always be "timeBoundary"; this is the first thing Druid looks at to figure out how to interpret the query|yes| |dataSource|A String defining the data source to query, very similar to a table in a relational database|yes| |context|An additional JSON Object which can be used to specify certain flags.|no| The format of the result is: ```json [ { "timestamp" : "2013-05-09T18:24:00.000Z", "result" : { "minTime" : "2013-05-09T18:24:00.000Z", "maxTime" : "2013-05-09T18:37:00.000Z" } } ] ```