TypedImperativeAggregate Expressions¶

TypedImperativeAggregate is an extension of the ImperativeAggregate abstraction for typed ImperativeAggregates.

Contract¶

Creating Aggregation Buffer¶

createAggregationBuffer(): T

See:

• BloomFilterAggregate
• ScalaAggregator

Used when:

• Collect is requested to deserialize
• TypedImperativeAggregate is requested to initialize

Deserializing¶

deserialize(
  storageFormat: Array[Byte]): T

See:

• BloomFilterAggregate
• ScalaAggregator

Used when:

• TypedImperativeAggregate is requested to merge

Interpreted Execution¶

eval(
  buffer: T): Any

See:

• BloomFilterAggregate
• ScalaAggregator

Used when:

• TypedImperativeAggregate is requested to execute (interpreted mode)

merge¶

merge(
  buffer: T,
  input: T): T

See:

• BloomFilterAggregate
• ScalaAggregator

Used when:

• TypedImperativeAggregate is requested to merge and mergeBuffersObjects

serialize¶

serialize(
  buffer: T): Array[Byte]

See:

• BloomFilterAggregate
• ScalaAggregator

Used when:

• TypedImperativeAggregate is requested to serializeAggregateBufferInPlace

update¶

update(
  buffer: T,
  input: InternalRow): T

See:

• BloomFilterAggregate
• ScalaAggregator

Used when:

• TypedImperativeAggregate is requested to update

Implementations¶

• BloomFilterAggregate
• ScalaAggregator
• others

Interpreted Expression Evaluation¶

eval(
  buffer: InternalRow): Any

eval is part of the Expression abstraction.

eval extracts the buffer object (for the given InternalRow) and evaluates the result.

Aggregation Buffer Attributes¶

aggBufferAttributes: Seq[AttributeReference]

aggBufferAttributes is part of the AggregateFunction abstraction.

aggBufferAttributes is a single AttributeReference:

Extracting Buffer Object¶

getBufferObject(
  bufferRow: InternalRow): T // (1)!
getBufferObject(
  buffer: InternalRow,
  offset: Int): T

1. Uses the mutableAggBufferOffset as the offset

getBufferObject requests the given InternalRow for the value (of type T) at the given offset that is of ObjectType type.

getBufferObject is used when:

• TypedImperativeAggregate is requested to mergeBuffersObjects, update, merge, eval, serializeAggregateBufferInPlace

ObjectType¶

anyObjectType: ObjectType

When created, TypedImperativeAggregate creates an ObjectType of a value of Scala AnyRef type.

The ObjectType is used in getBufferObject.