union_sketch(x) – Constructs a sketch set to estimate reach for large values by collecting multiple

union_hyperloglog(x) – Merges multiple hyperloglogs together. Platforms: WhereOS, Spark, Hive Class: brickhouse.udf.hll.UnionHyperLogLogUDAF More functions can

union_map(x) – Returns a map which contains the union of an aggregation of maps Platforms:

unhex(expr) – Converts hexadecimal `expr` to binary. Platforms: WhereOS, Spark, Hive Class: org.apache.spark.sql.catalyst.expressions.Unhex More functions

unbase64(str) – Converts the argument from a base 64 string `str` to a binary. Platforms:

unbase91(string) – Convert a BASE91 string to a binary SELECT inflate(unbase91(base91(deflate(‘aaaaaaaaaaaaaaaabbbbccc’)))); aaaaaaaaaaaaaaaabbbbccc Platforms: WhereOS, Spark,