Note
This view is introduced since OceanBase Database V4.0.0.
Purpose
This view displays the histogram data (endpoints of each histogram) of all subpartitioned tables in the current tenant.
Columns
| Column | Type | Nullable? | Description |
|---|---|---|---|
| OWNER | varchar(128) | NO | The owner of the table. |
| TABLE_NAME | varchar(128) | NO | The name of the table that contains the histogram. |
| SUBPARTITION_NAME | varchar(128) | NO | The name of the subpartition that contains the histogram. |
| COLUMN_NAME | varchar(128) | NO | The name of the column that contains the histogram. |
| ENDPOINT_NUMBER | decimal(10,0) | NO | The cumulative frequency of the bucket. |
| ENDPOINT_VALUE | decimal(10,0) | NO | The normalized value of the bucket endpoint. |
| ENDPOINT_ACTUAL_VALUE | text | NO | The value of the bucket endpoint. |
| ENDPOINT_ACTUAL_VALUE_RAW | text | NO | The binary value of the bucket endpoint. |
| ENDPOINT_REPEAT_COUNT | decimal(10,0) | NO | The frequency of the bucket endpoint value. |
Sample query
In the system tenant, query the histogram information of the subpartitions of the partitioned table sales_subpart.
obclient [oceanbase]> SELECT * FROM oceanbase.DBA_SUBPART_HISTOGRAMS WHERE TABLE_NAME ='sales_subpart';
The query result is as follows:
+----------+---------------+-------------------+-------------+-----------------+----------------+-----------------------+---------------------------+-----------------------+
| OWNER | TABLE_NAME | SUBPARTITION_NAME | COLUMN_NAME | ENDPOINT_NUMBER | ENDPOINT_VALUE | ENDPOINT_ACTUAL_VALUE | ENDPOINT_ACTUAL_VALUE_RAW | ENDPOINT_REPEAT_COUNT |
+----------+---------------+-------------------+-------------+-----------------+----------------+-----------------------+---------------------------+-----------------------+
| test | sales_subpart | p2023sp0 | quantity | 127 | NULL | 1 | 04053F0001 | 127 |
| test | sales_subpart | p2023sp0 | product_id | 127 | NULL | 8 | 04053F0008 | 63 |
| test | sales_subpart | p2023sp0 | product_id | 64 | NULL | 4 | 04053F0004 | 64 |
| test | sales_subpart | p2023sp1 | quantity | 190 | NULL | 1 | 04053F0001 | 190 |
| test | sales_subpart | p2023sp1 | product_id | 190 | NULL | 9 | 04053F0009 | 63 |
| test | sales_subpart | p2023sp1 | product_id | 127 | NULL | 5 | 04053F0005 | 63 |
| test | sales_subpart | p2023sp1 | product_id | 64 | NULL | 1 | 04053F0001 | 64 |
| test | sales_subpart | p2023sp2 | quantity | 127 | NULL | 1 | 04053F0001 | 127 |
| test | sales_subpart | p2023sp2 | product_id | 127 | NULL | 6 | 04053F0006 | 63 |
| test | sales_subpart | p2023sp2 | product_id | 64 | NULL | 2 | 04053F0002 | 64 |
| test | sales_subpart | p2023sp3 | quantity | 191 | NULL | 1000 | 04053F00E807 | 6 |
| test | sales_subpart | p2023sp3 | quantity | 185 | NULL | 1 | 04053F0001 | 185 |
| test | sales_subpart | p2023sp3 | product_id | 191 | NULL | 999 | 04053F00E707 | 64 |
| test | sales_subpart | p2023sp3 | product_id | 127 | NULL | 7 | 04053F0007 | 63 |
| test | sales_subpart | p2023sp3 | product_id | 64 | NULL | 3 | 04053F0003 | 64 |
| test | sales_subpart | p2024sp0 | quantity | 73 | NULL | 1 | 04053F0001 | 73 |
| test | sales_subpart | p2024sp0 | product_id | 73 | NULL | 8 | 04053F0008 | 37 |
| test | sales_subpart | p2024sp0 | product_id | 36 | NULL | 4 | 04053F0004 | 36 |
| test | sales_subpart | p2024sp1 | quantity | 110 | NULL | 1 | 04053F0001 | 110 |
| test | sales_subpart | p2024sp1 | product_id | 110 | NULL | 9 | 04053F0009 | 37 |
| test | sales_subpart | p2024sp1 | product_id | 73 | NULL | 5 | 04053F0005 | 37 |
| test | sales_subpart | p2024sp1 | product_id | 36 | NULL | 1 | 04053F0001 | 36 |
| test | sales_subpart | p2024sp2 | quantity | 73 | NULL | 1 | 04053F0001 | 73 |
| test | sales_subpart | p2024sp2 | product_id | 73 | NULL | 6 | 04053F0006 | 37 |
| test | sales_subpart | p2024sp2 | product_id | 36 | NULL | 2 | 04053F0002 | 36 |
| test | sales_subpart | p2024sp3 | quantity | 109 | NULL | 1000 | 04053F00E807 | 4 |
| test | sales_subpart | p2024sp3 | quantity | 105 | NULL | 1 | 04053F0001 | 105 |
| test | sales_subpart | p2024sp3 | product_id | 109 | NULL | 999 | 04053F00E707 | 36 |
| test | sales_subpart | p2024sp3 | product_id | 73 | NULL | 7 | 04053F0007 | 37 |
| test | sales_subpart | p2024sp3 | product_id | 36 | NULL | 3 | 04053F0003 | 36 |
+----------+---------------+-------------------+-------------+-----------------+----------------+-----------------------+---------------------------+-----------------------+
30 rows in set
References
DBA_TAB_HISTOGRAMS: View histogram statistics at the table level.
DBA_PART_HISTOGRAMS: View histogram statistics at the partition level.
DBA_TAB_STATISTICS: View column statistics at the table level.
DBA_TAB_COL_STATISTICS: View global column statistics.
DBA_PART_COL_STATISTICS: View column statistics at the partition level.
DBA_SUBPART_HISTOGRAMS: View histogram statistics at the subpartition level.
DBA_IND_STATISTICS: View index statistics.
For more information about how to collect statistics, see the following topics: