ADVANCED_HISTOGRAMS

This view contains information about histograms that have been collected by automatic statistics or using ANALYZE.

For more information about this command and which columns SingleStore collects histograms on, see Statistics and Sampling Tasks.

Each histogram provides information about the distribution of data in a column, and consists of several buckets - the groups/intervals among which data points are divided. Each histogram bucket is displayed as a row in this view.

Column Name

Description

DATABASE_NAME

The name of the database.

TABLE_NAME

The name of the table.

COLUMN_NAME

The name of the column.

JSON_KEY

When there is a histogram on a json_key as part of a json column, there's an entry here for each (column, json_key) pair. For non-json columns JSON_KEY is NULL.

TYPE

The data type of the column.

VERSION

Internal version number of the histogram format, which may change if the way histograms are stored is changed. Its current value is 100.

BUCKET_COUNT

The number of buckets in the histogram.

BUCKET_INDEX

The index for a given bucket within its histogram.

RANGE_MIN

The minimum value in a given bucket.

RANGE_MAX

The maximum value in a given bucket.

UNIQUE_COUNT

The number of distinct data values that are in a given bucket.

CARDINALITY

The number of rows in a given bucket.

UNIQUE_COUNT_CUMULATIVE

The cumulative number of distinct data values in this column, up to the current bucket index.

CARDINALITY_CUMULATIVE

The cumulative number of rows in this column, up to the current bucket index.

Last modified: March 8, 2024

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