SingleStore DB

information_schema.OPTIMIZER_STATISTICS

This table contains column statistics calculated on columns when a table is processed by autostats or the ANALYZE command. It displays one row per column per table. The values displayed here are estimates used for query optimization, they are not exact.

Column Name

Description

DATABASE_NAME

The name of the related database.

TABLE_NAME

The name of the related table.

COLUMN_NAME

The name of the related column.

ROW_COUNT

The number of rows in a given table.

NULL_COUNT

The number of null values stored within a given column.

CARDINALITY

The number of unique values stored within a given column.

AUTOSTATS_ENABLED

Whether or not autostats are currently enabled for a given column.

AUTOSTATS_OUTDATED

Whether or not autostats are considered too out-of-date to be used currently.

AUTOSTATS_ROW_COUNT

This column is deprecated and no longer used and its value is always NULL. See ROW_COUNT instead.

AUTOSTATS_NULL_COUNT

This column is deprecated and no longer used and its value is always NULL. See NULL_COUNT instead.

AUTOSTATS_CARDINALITY

This column is deprecated and no longer used and its value is always NULL. See CARDINALITY instead.

ADVANCED_HISTOGRAMS

Whether advanced histograms are collected on this column.

LEGACY_HISTOGRAMS

Whether legacy histograms are collected on this column. This column is now deprecated.

RANGE_STATS

Whether histograms (of either type) are collected on this column .

SAMPLE_SIZE

The sample size collected to build histograms on this column.

LAST_UPDATED

The timestamp at which autostats were last updated for a given column.