3.108 ALL_TAB_HISTOGRAMS

ALL_TAB_HISTOGRAMS describes histograms on tables and views accessible to the current user.

The ALL_TAB_HISTOGRAMS view may contain a one-bucket histogram, which in fact signifies "No histogram" to the Oracle Database software.  Therefore, it should not be queried to indicate the presence or absence of a histogram on a particular column.  Instead, query the value of column HISTOGRAM in the ALL_TAB_COL_STATISTICS view.

Related Views

  • DBA_TAB_HISTOGRAMS describes histograms on all tables and views in the database.

  • USER_TAB_HISTOGRAMS describes histograms on all tables and views owned by the current user. This view does not display the OWNER column.

Note:

These views are populated only if you collect statistics on the table using the DBMS_STATS package. For more information, see Oracle Database PL/SQL Packages and Types Reference.

Column Datatype NULL Description

OWNER

VARCHAR2(128)

Owner of the table

TABLE_NAME

VARCHAR2(128)

Name of the table

COLUMN_NAME

VARCHAR2(4000)

Column name or attribute of the object type column

ENDPOINT_NUMBER

NUMBER

Histogram bucket number

ENDPOINT_VALUE

NUMBER

Normalized endpoint value for this bucket

ENDPOINT_ACTUAL_VALUE

VARCHAR2(4000)

Actual (not normalized) string value of the endpoint for this bucket

ENDPOINT_ACTUAL_VALUE_RAW

RAW(1000)

Endpoint actual value in raw format

ENDPOINT_REPEAT_COUNT

NUMBER

Frequency of the endpoint (applies only to hybrid histograms, and is set to 0 for other histogram types)

SCOPE

VARCHAR2(7)

The value is SHARED for statistics gathered on any table other than global temporary tables.

For a global tempoary table, the possible values are:

  • SESSION - Indicates that the statistics are session-specific

  • SHARED - Indicates that the statistics are shared across all sessions

See Oracle Database PL/SQL Packages and Types Reference for information about using the GLOBAL_TEMP_TABLE_STATS preference of the DBMS_STATS package to control whether to gather session or shared statistics for global temporary tables.

See Also: