Statistics Query

Function Description

The total number of entities that meet the query conditions is returned. The detailed information about the data is not returned. The setCountOnly() parameter is set in the code.

Below is an example of the code implementation.

Sample Code

public void testCountOnlyQuery() { 
  LOG.info("Entering testCountOnlyQuery."); 

  try (Table table = conn.getTable(tableName)) { 
    // Using Table instance to create LemonTable. 
    LemonTable lemonTable = new LemonTable(table); 
    // Build LemonQuery. 
    LemonQuery query = LemonQuery.builder() 
      // Set ad-hoc query condition. 
      .setQuery("education:bachelor OR education:master") 
      // just return how many entities meet the query condition, without any rowkey/column 
      .setCountOnly() 
      .build(); 
    ResultSet resultSet = lemonTable.query(query); 
    // Read result rows. 
    int count = resultSet.getCount(); 
    LOG.info("the entity count of query is " + count); 
  } catch (IOException e) { 
    LOG.error("testCountOnlyQuery failed ", e); 
  } 

  LOG.info("Exiting testCountOnlyQuery."); 
}