ALL_TAB_COL_STATISTICS

ALL_TAB_COL_STATISTICS displays column statistics and histogram information extracted from "ALL_TAB_COLUMNS".

Related Views

  • DBA_TAB_COL_STATISTICS displays such information extracted from "DBA_TAB_COLUMNS".

  • USER_TAB_COL_STATISTICS displays such information extracted from "USER_TAB_COLUMNS". This view does not display the OWNER column.

Column Datatype NULL Description
OWNER VARCHAR2(30)   Owner of the table
TABLE_NAME VARCHAR2(30)   Name of the table
COLUMN_NAME VARCHAR2(30)   Column name
NUM_DISTINCT NUMBER   Number of distinct values in the column
LOW_VALUE RAW(32)   Low value in the column
HIGH_VALUE RAW(32)   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
LAST_ANALYZED DATE   Date on which this column was most recently analyzed
SAMPLE_SIZE NUMBER   Sample size used in analyzing this column
GLOBAL_STATS VARCHAR2(3)   For partitioned tables, indicates whether column statistics were collected for the table as a whole (YES) or were estimated from statistics on underlying partitions and subpartitions (NO)
USER_STATS VARCHAR2(3)   Indicates whether statistics were entered directly by the user (YES) or not (NO)
AVG_COL_LEN NUMBER   Average length of the column (in bytes)
HISTOGRAM VARCHAR2(15)   Indicates existence/type of histogram:
  • NONE

  • FREQUENCY

  • HEIGHT BALANCED