ALL_PART_COL_STATISTICS

ALL_PART_COL_STATISTICS displays column statistics and histogram information for the table partitions accessible to the current user.

Column Datatype NULL Description
OWNER VARCHAR2(128) NOT NULL Owner of the partitioned table
TABLE_NAME VARCHAR2(128) NOT NULL Name of the table
PARTITION_NAME VARCHAR2(128)   Name of the table partition
COLUMN_NAME VARCHAR2(4000)   Name of the column
NUM_DISTINCT NUMBER   Number of distinct values in the column
LOW_VALUE RAW(1000)   Low value in the column
HIGH_VALUE RAW(1000)   High value in the column
DENSITY NUMBER  

If a histogram is available on COLUMN_NAME, then this column displays the selectivity of a value that spans fewer than 2 endpoints in the histogram. It does not represent the selectivity of values that span 2 or more endpoints.

If a histogram is not available on COLUMN_NAME, then the value of this column is 1/NUM_DISTINCT.

NUM_NULLS NUMBER   Number of NULLs in the column
NUM_BUCKETS NUMBER   Number of buckets in histogram for the column
SAMPLE_SIZE NUMBER   Sample size used in analyzing the column
LAST_ANALYZED DATE   Date on which the column was most recently analyzed
GLOBAL_STATS VARCHAR2(3)   GLOBAL_STATS will be YES if statistics have been gathered or NO if statistics have been aggregated from subpartitions or have not been gathered
USER_STATS VARCHAR2(3)   Indicates whether statistics were entered directly by the user (YES) or not (NO)
NOTES VARCHAR2(81)  

Additional properties of the statistics, if any. Possible values:

  • ADAPTIVE_SAMPLING: The column has synopses, and the synopses are in the adaptive sampling format introduced in Oracle Database 11g Release 1 (11.1).

  • HIST_FOR_INCREM_STATS: A histogram used to support incremental statistics has been created and it is not used for optimization.
  • HISTOGRAM_ONLY: Table statistics were gathered using the GATHER AUTO option and histograms were gathered without re-gathering other table and column statistics.

  • HYPERLOGLOG: The column has synopses, and the synopses are in the HyperLogLog format introduced in Oracle Database 12c Release 2 (12.2.0.1).

  • INCREMENTAL: The column has synopses.

  • STATS_ON_LOAD: Online statistics were gathered during direct path load.

This column can be used to determine whether synopses in the adaptive sampling format have been phased out entirely and purged properly.
AVG_COL_LEN NUMBER   Average length of the column (in bytes)
HISTOGRAM VARCHAR2(15)  

Indicates existence/type of histogram:

  • NONE

  • FREQUENCY

  • HEIGHT BALANCED

  • HYBRID

  • TOP-FREQUENCY

See Also: