HashExpression¶

HashExpression[E] is an extension of the Expression abstraction for hashing expressions that calculate hash value (for a group of expressions).

Contract¶

Computing Hash¶

computeHash(
  value: Any,
  dataType: DataType,
  seed: E): E

Used when:

• HashExpression is requested to eval and doGenCode

hasherClassName¶

hasherClassName: String

Used when:

• HashExpression is requested to genHashInt, genHashLong, genHashBytes, genHashCalendarInterval, genHashString

Seed¶

seed: E

Used when:

• HashExpression is requested to eval and doGenCode

Implementations¶

• HiveHash
• Murmur3Hash
• XxHash64

Interpreted Expression Evaluation¶

eval(
  input: InternalRow): Any

eval...FIXME

eval is part of the Expression abstraction.

doGenCode¶

doGenCode(
  ctx: CodegenContext,
  ev: ExprCode): ExprCode

doGenCode...FIXME

doGenCode is part of the Expression abstraction.