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Updated on 2024-05-29 GMT+08:00
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SHOW STATS

Syntax

SHOW STATS FOR table_name;

SHOW STATS FOR (SELECT * FROM table [WHERE condition]);

Remarks

ANALYZE should be performed on the table before SHOW STATS. For details, see ANALYZE. If you run the show stats command on the target table before running ANALYZE, all values are null.

Description

Returns the approximate statistics of a table.

Returns the statistics about each column.

Column

Description

column_name

Column name (Summary Row: NULL)

data_size

The total size of all values in the column (in bytes)

distinct_values_count

Number of different values in the column

nulls_fraction

Fractions whose values are NULL in the column

row_count

Number of lines (returned only for summary lines)

low_value

Minimum value found in this column (only for some types)

high_value

Maximum value found in this column (applicable only to some types)

Example

SHOW STATS FOR orders;
SHOW STATS FOR (SELECT * FROM orders);
  • Before analyzing the nation table:
    SHOW STATS FOR nation; 
column_name | data_size | distinct_values_count | nulls_fraction | row_count | low_value | high_value 
-------------|-----------|-----------------------|----------------|-----------|-----------|------------
 name        |      NULL |                  NULL |           NULL |      NULL | NULL      | NULL       
 regionkey   |      NULL |                  NULL |           NULL |      NULL | NULL      | NULL       
 NULL        |      NULL |                  NULL |           NULL |       6.0 | NULL      | NULL       
(3 rows)
  • After analyzing the nation table:
    Analyze nation;
ANALYZE: 6 rows

-- Query the analysis result.
SHOW STATS FOR nation;
column_name | data_size | distinct_values_count | nulls_fraction | row_count | low_value | high_value 
-------------|-----------|-----------------------|----------------|-----------|-----------|------------
 name        |      45.0 |                   5.0 |            0.0 |      NULL | NULL      | NULL       
 regionkey   |      NULL |                   2.0 |            0.0 |      NULL | 0         | 2          
 NULL        |      NULL |                  NULL |           NULL |       6.0 | NULL      | NULL       
(3 rows)
Parent topic: DDL Syntax