SYSCOLUMNSTATISTICS System View
The SYSCOLUMNSTATISTICS
table view describes the statistics for a
specific table column within the current database.
SYS.SYSCOLUMNSTATISTICS
is a system view.
The following table shows the contents of the SYSCOLUMNSTATISTICS
system view.
Column Name | Type | Length | Nullable | Contents |
---|---|---|---|---|
SCHEMANAME |
VARCHAR |
32672 |
YES |
The name of the schema. |
TABLENAME |
VARCHAR |
32672 |
YES |
The name of the table. |
COLUMNNAME |
VARCHAR |
32672 |
YES |
The name of the column. |
CARDINALITY |
BIGINT |
19 |
YES |
The estimated number of distinct values for the column. |
NULL_COUNT |
BIGINT |
19 |
YES |
The number of rows in the table that have NULL for the column. |
NULL_FRACTION |
REAL |
23 |
YES |
The ratio of NULL_COUNT / TOTAL_ROW_COUNT |
MIN_VALUE |
VARCHAR |
32672 |
YES |
The minimum value for the column. |
MAX_VALUE |
VARCHAR |
32672 |
YES |
The maximum value for the column. |
QUANTILES |
VARCHAR |
32672 |
YES |
The quantiles statistics sketch for the column. |
FREQUENCIES |
VARCHAR |
32672 |
YES |
The frequencies statistics sketch for the column. |
THETA |
VARCHAR |
32672 |
YES |
The theta statistics sketch for the column. |
The QUANTILES
, FREQUENCIES
, and THETA
values are all sketches
computed using the Yahoo Data Sketches library, which you can read about
here: https://datasketches.github.io/