Package org.apache.arrow.adbc.core

Enum StandardStatistics

java.lang.Object
java.lang.Enum<StandardStatistics>
org.apache.arrow.adbc.core.StandardStatistics
All Implemented Interfaces:
Serializable, Comparable<StandardStatistics>
public enum StandardStatistics extends Enum<StandardStatistics>
Definitions of standard statistic names/keys.

Statistic names are returned from AdbcConnection.getStatistics(String, String, String, boolean) in a dictionary-encoded form. This class provides the names and dictionary-encoded form of statistics defined by ADBC.

  • Enum Constant Details

    • AVERAGE_BYTE_WIDTH

      public static final StandardStatistics AVERAGE_BYTE_WIDTH
      The average byte width statistic. The average size in bytes of a row in the column. Value type is float64.

      For example, this is roughly the average length of a string for a string column.

    • DISTINCT_COUNT

      public static final StandardStatistics DISTINCT_COUNT
      The distinct value count (NDV) statistic. The number of distinct values in the column. Value type is int64 (when not approximate) or float64 (when approximate).

    • MAX_BYTE_WIDTH

      public static final StandardStatistics MAX_BYTE_WIDTH
      The max byte width statistic. The maximum size in bytes of a row in the column. Value type is int64 (when not approximate) or float64 (when approximate).

      For example, this is the maximum length of a string for a string column.

    • MAX_VALUE

      public static final StandardStatistics MAX_VALUE
      The max value statistic. Value type is column-dependent.

    • MIN_VALUE

      public static final StandardStatistics MIN_VALUE
      The min value statistic. Value type is column-dependent.

    • NULL_COUNT

      public static final StandardStatistics NULL_COUNT
      The null count statistic. The number of values that are null in the column. Value type is int64 (when not approximate) or float64 (when approximate).

    • ROW_COUNT

      public static final StandardStatistics ROW_COUNT
      The row count statistic. The number of rows in the column or table. Value type is int64 (when not approximate) or float64 (when approximate).

  • Method Details

    • values

      public static StandardStatistics[] values()
      Returns an array containing the constants of this enum type, in the order they are declared.
      Returns:
      an array containing the constants of this enum type, in the order they are declared

    • valueOf

      public static StandardStatistics valueOf(String name)
      Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)
      Parameters:
      name - the name of the enum constant to be returned.
      Returns:
      the enum constant with the specified name
      Throws:
      IllegalArgumentException - if this enum type has no constant with the specified name
      NullPointerException - if the argument is null

    • getName

      public String getName()
      Get the statistic name.

    • getKey

      public short getKey()
      Get the dictionary-encoded name.