Package dev.frostlake.functions.aggregate

Class ArrayUniqueAgg

java.lang.Object
dev.frostlake.functions.BuiltInFunction
dev.frostlake.functions.AggregateFunction
dev.frostlake.functions.aggregate.ArrayUniqueAgg
public class ArrayUniqueAgg extends AggregateFunction
ARRAY_UNIQUE_AGG(expr) — an aggregate that collects the DISTINCT non-NULL scalar input values (each input row contributes a single element, not an array) into a VARIANT ARRAY. Mirrors Snowflake's ARRAY_UNIQUE_AGG.

  • Constructor Details

    • ArrayUniqueAgg

      public ArrayUniqueAgg()

  • Method Details

    • structuredRejection

      public SemiStructuredRejection structuredRejection(int position)
      The same divergence ARRAY_AGG has: live, ARRAY_UNIQUE_AGG(o) and ARRAY_UNIQUE_AGG(a) collect their values while ARRAY_UNIQUE_AGG(so), (sa) and (sm) are "Invalid argument types for function 'ARRAY_UNIQUE_AGG'" naming the whole structured type.
      Overrides:
      structuredRejection in class BuiltInFunction
      Parameters:
      position - the zero-based argument position being asked about
      Returns:
      the extra refusal this position gives a structured value, or NONE when undeclared

    • createAccumulator

      public AggregateFunction.Accumulator createAccumulator()
      Description copied from class: AggregateFunction
      Creates the fresh, empty per-group state for one evaluation of this aggregate; the executor makes one per group (or per window partition) and never shares them.
      Specified by:
      createAccumulator in class AggregateFunction
      Returns:
      a new accumulator starting from this aggregate's empty-group state

    • evaluate

      public Object evaluate(List<Object> args)
      Description copied from class: BuiltInFunction
      Computes the function's result over its already-evaluated argument values. A SQL NULL argument arrives as Java null, and returning null makes the SQL result NULL.
      Specified by:
      evaluate in class BuiltInFunction
      Parameters:
      args - the argument values, in call order
      Returns:
      the function's value for these arguments, or null for SQL NULL

    • getMinArgCount

      public int getMinArgCount()
      Description copied from class: BuiltInFunction
      The fewest arguments a call to this function may pass; fewer is an argument-count error.
      Specified by:
      getMinArgCount in class BuiltInFunction
      Returns:
      the minimum accepted argument count

    • getMaxArgCount

      public int getMaxArgCount()
      Description copied from class: BuiltInFunction
      The most arguments a call to this function may pass; Integer.MAX_VALUE marks a variadic function (see BuiltInFunction.isVariadic()).
      Specified by:
      getMaxArgCount in class BuiltInFunction
      Returns:
      the maximum accepted argument count