Note
This view is available starting with V3.2.1.
Purpose
This view displays histogram information of all partitions in the partitioned tables accessible to the current user.
Applicability
This view is available only in OceanBase Database in Oracle mode.
Columns
| Column | Type | Nullable | Description |
|---|---|---|---|
| OWNER | VARCHAR2(128) | NO | The user to which the histogram belongs. |
| TABLE_NAME | VARCHAR2(128) | NO | The name of the table to which the histogram belongs. |
| PARTITION_NAME | VARCHAR2(128) | NO | The name of the partition to which the histogram belongs. |
| COLUMN_NAME | VARCHAR2(128) | NO | The name of the column to which the histogram belongs. |
| ENDPOINT_NUMBER | NUMBER | NO | The cumulative frequency of the bucket. |
| ENDPOINT_VALUE | NUMBER | NO | The normalized value of the bucket endpoint. |
| ENDPOINT_ACTUAL_VALUE | VARCHAR2(4000) | NO | The value of the bucket endpoint. |
| ENDPOINT_ACTUAL_VALUE_RAW | VARCHAR2(4000) | NO | The binary value of the bucket endpoint. |
| ENDPOINT_REPEAT_COUNT | NUMBER | NO | The frequency of the bucket endpoint value. |
Sample query
Query the histogram information of the partitions of the T_SUBPART table in the partitioned tables accessible to the current user.
obclient [SYS]> SELECT * FROM SYS.ALL_PART_HISTOGRAMS WHERE TABLE_NAME ='T_SUBPART';
The query result is as follows:
+-------+------------+----------------+-------------+-----------------+----------------+-----------------------+---------------------------+-----------------------+
| OWNER | TABLE_NAME | PARTITION_NAME | COLUMN_NAME | ENDPOINT_NUMBER | ENDPOINT_VALUE | ENDPOINT_ACTUAL_VALUE | ENDPOINT_ACTUAL_VALUE_RAW | ENDPOINT_REPEAT_COUNT |
+-------+------------+----------------+-------------+-----------------+----------------+-----------------------+---------------------------+-----------------------+
| SYS | T_SUBPART | P3 | QUANTITY | 200 | NULL | 1000 | 1000 | 2 |
| SYS | T_SUBPART | P3 | QUANTITY | 198 | NULL | 1 | 1 | 198 |
| SYS | T_SUBPART | P3 | ID | 200 | NULL | 999 | 999 | 20 |
| SYS | T_SUBPART | P3 | ID | 180 | NULL | 9 | 9 | 20 |
| SYS | T_SUBPART | P3 | ID | 160 | NULL | 8 | 8 | 20 |
| SYS | T_SUBPART | P3 | ID | 140 | NULL | 7 | 7 | 20 |
| SYS | T_SUBPART | P3 | ID | 120 | NULL | 6 | 6 | 20 |
| SYS | T_SUBPART | P3 | ID | 100 | NULL | 5 | 5 | 20 |
| SYS | T_SUBPART | P3 | ID | 80 | NULL | 4 | 4 | 20 |
| SYS | T_SUBPART | P3 | ID | 60 | NULL | 3 | 3 | 20 |
| SYS | T_SUBPART | P3 | ID | 40 | NULL | 2 | 2 | 20 |
| SYS | T_SUBPART | P3 | ID | 20 | NULL | 1 | 1 | 20 |
| SYS | T_SUBPART | P2 | QUANTITY | 300 | NULL | 1000 | 1000 | 3 |
| SYS | T_SUBPART | P2 | QUANTITY | 297 | NULL | 1 | 1 | 297 |
| SYS | T_SUBPART | P2 | ID | 300 | NULL | 999 | 999 | 30 |
| SYS | T_SUBPART | P2 | ID | 270 | NULL | 9 | 9 | 30 |
| SYS | T_SUBPART | P2 | ID | 240 | NULL | 8 | 8 | 30 |
| SYS | T_SUBPART | P2 | ID | 210 | NULL | 7 | 7 | 30 |
| SYS | T_SUBPART | P2 | ID | 180 | NULL | 6 | 6 | 30 |
| SYS | T_SUBPART | P2 | ID | 150 | NULL | 5 | 5 | 30 |
| SYS | T_SUBPART | P2 | ID | 120 | NULL | 4 | 4 | 30 |
| SYS | T_SUBPART | P2 | ID | 90 | NULL | 3 | 3 | 30 |
| SYS | T_SUBPART | P2 | ID | 60 | NULL | 2 | 2 | 30 |
| SYS | T_SUBPART | P2 | ID | 30 | NULL | 1 | 1 | 30 |
| SYS | T_SUBPART | P1 | QUANTITY | 500 | NULL | 1000 | 1000 | 5 |
| SYS | T_SUBPART | P1 | QUANTITY | 495 | NULL | 1 | 1 | 495 |
| SYS | T_SUBPART | P1 | ID | 500 | NULL | 999 | 999 | 50 |
| SYS | T_SUBPART | P1 | ID | 450 | NULL | 9 | 9 | 50 |
| SYS | T_SUBPART | P1 | ID | 400 | NULL | 8 | 8 | 50 |
| SYS | T_SUBPART | P1 | ID | 350 | NULL | 7 | 7 | 50 |
| SYS | T_SUBPART | P1 | ID | 300 | NULL | 6 | 6 | 50 |
| SYS | T_SUBPART | P1 | ID | 250 | NULL | 5 | 5 | 50 |
| SYS | T_SUBPART | P1 | ID | 200 | NULL | 4 | 4 | 50 |
| SYS | T_SUBPART | P1 | ID | 150 | NULL | 3 | 3 | 50 |
| SYS | T_SUBPART | P1 | ID | 100 | NULL | 2 | 2 | 50 |
| SYS | T_SUBPART | P1 | ID | 50 | NULL | 1 | 1 | 50 |
+-------+------------+----------------+-------------+-----------------+----------------+-----------------------+---------------------------+-----------------------+
36 rows in set
References
To view histogram information of partitions of all partitioned tables in the current tenant, query DBA_PART_HISTOGRAMS.
To view histogram information of partitions of all partitioned tables in the current tenant, query USER_PART_HISTOGRAMS.
To view table-level histogram statistics, query the following views:
To view subpartition-level histogram statistics, query the following views:
To view table-level column statistics, query the following views:
To view global-level column statistics, query the following views:
To view partition-level column statistics, query the following views:
To view subpartition-level column statistics, query the following views:
To view index statistics, query the following views:
For information about how to collect statistics, see the following topics: