Ways to query Pinot
Pinot can be queried via a broker endpoint as follows. This example assumes broker is running on localhost:8099
The Pinot REST API can be accessed by invoking POST
operation with a JSON body containing the parameter sql
to the /query/sql
endpoint on a broker.
Note
This endpoint is deprecated, and will soon be removed. The standard-SQL endpoint is the recommended endpoint.
The PQL endpoint can be accessed by invoking POST
operation with a JSON body containing the parameter pql
to the /query
endpoint on a broker.
Query Console can be used for running ad-hoc queries (checkbox available to query the PQL endpoint). The Query Console can be accessed by entering the <controller host>:<controller port>
in your browser
You can also query using the pinot-admin
scripts. Make sure you follow instructions in Getting Pinot to get Pinot locally, and then
Here's a list of the clients available to query Pinot from your application
Coming soon - JDBC client
Response is returned in a SQL-like tabular structure. Note, this is the response returned from the standard-SQL endpoint. For PQL endpoint response, skip to PQL endpoint response
where,
Note
PQL endpoint is deprecated, and will soon be removed. The standard sql endpoint is the recommended endpoint.
The response received from PQL endpoint is different depending on the type of the query.
Response Field
Description
resultTable
This contains everything needed to process the response
resultTable.dataSchema
This describes schema of the response (columnNames and their dataTypes)
resultTable.dataSchema.columnNames
columnNames in the response.
resultTable.dataSchema.columnDataTypes
DataTypes for each column
resultTable.rows
Actual content with values. This is an array of arrays. number of rows depends on the limit value in the query. The number of columns in each row is equal to the length of (resultTable.dataSchema.columnNames)
timeUsedms
Total time taken as seen by the broker before sending the response back to the client
totalDocs
This is number of documents/records in the table
numServersQueried
represents the number of servers queried by the broker (note that this may be less than the total number of servers since broker can apply some optimizations to minimize the number of servers)
numServersResponded
This should be equal to the numServersQueried. If this is not the same, then one of more servers might have timed out. If numServersQueried != numServersResponded the results can be considered partial and clients can retry the query with exponential back off.
numSegmentsQueried
Total number of segmentsQueried for this query. it may be less than the total number of segments since broker can apply optimizations.
numSegmentsMatched
This is the number of segments actually processed. This indicates the effectiveness of pruning logic (based on partitioning, time etc).
numSegmentsProcessed
Actual number of segments that were processed. This is where the majority of the time is spent.
numDocScanned
The number of docs/records that were scanned to process the query. This includes the docs scanned in filter phase (this can be zero if columns in query are indexed) and post filter.
numEntriesScannedInFilter
This along with numEntriesScannedInPostFilter should give an idea on where most of the time is spent during query processing. If this is high, enabling indexing for columns in tableConfig can be one way to bring it down.
numEntriesScannedPostFilter
This along with numEntriesScannedInPostFilter should give an idea on where most of the time is spent during query processing. A high number for this means the selectivity is low (i.e. pinot needs to scan a lot of records to answer the query). If this is high, adding regular inverted/bitmap index will not help. However, consider using start-tree index.
numGroupsLimitReached
If the query has group by clause and top K, pinot drops new entries after the numGroupsLimit is reached. If this boolean is set to true then the query result may not be accurate. Note that the default value for numGroupsLimit is 100k and should be sufficient for most use cases.
exceptions
Will contain the stack trace if there is any exception processing the query.
segmentStatistics
N/A
traceInfo
If trace is enabled (can be enabled for each query), this will contain the timing for each stage and each segment. Advanced feature and intended for dev/debugging purposes