public class GROUP_CONCAT extends AggregateBase<IV> implements INeedsMaterialization
|Modifier and Type||Class and Description|
|Modifier and Type||Field and Description|
|Constructor and Description|
|Modifier and Type||Method and Description|
Return the final value.
Return the current value of the aggregate (this has a side-effect on the internal state of the
We always need to have the materialized values.
Reset the aggregate's internal state.
__replaceArg, _set, annotations, annotationsCopy, annotationsEqual, annotationsRef, argIterator, args, argsCopy, arity, clearAnnotations, clearProperty, deepCopy, deepCopy, get, getProperty, setArg, setProperty, setUnboundProperty, toArray, toArray
annotationsEqual, annotationsToString, annotationsToString, annotationValueToString, checkArgs, clone, equals, getEvaluationContext, getId, getProperty, getRequiredProperty, hashCode, indent, isController, mutation, shortenName, toShortString, toString, toString
finalize, getClass, notify, notifyAll, wait, wait, wait
annotations, argIterator, args, arity, clone, get, getEvaluationContext, getId, getProperty, getRequiredProperty, isController, setProperty, toArray, toArray, toShortString, toString
protected transient BigdataValueFactory vf
public GROUP_CONCAT(GROUP_CONCAT op)
public GROUP_CONCAT(boolean distinct, IValueExpression<IV> expr, String namespace, String sep)
var- The variable whose values will be combined.
sep- The separator string (note that a space (0x20) is the default in the SPARQL recommendation).
public void reset()
public IV done()
public IV get(IBindingSet bindingSet)
IAggregateoperator). Functions which can not produce an intermediate result, such as AVERAGE, MAY return
Note: If evaluation of the
IAggregate throws an error, then that
error must be "sticky" and reported out by
IAggregate.done() as well. This
contract is relied on to correctly propagate errors within a group when
using incremental (pipelined) evaluation of
error state is cleared by
Operation is not implemented by this class and must be overridden if the
AggregateBase is to be directly evaluated. However, note that the
computation of aggregate functions is often based on hard coded
recognition of the appropriate function code.
Note: DISTINCT is merely carried as a marker on COUNT (and the other
aggregate functions). The application of DISTINCT to the inner expression
to form a column projection is handled by the driving evaluation logic
rather than by
bindingSet- The binding set.
public INeedsMaterialization.Requirement getRequirement()
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