timescaledb_information.compression_settings
Get information about compression-related settings for hypertables. Each row of the view provides information about individual orderby and segmentby columns used by compression.
Available Columns
Name | Type | Description |
---|---|---|
hypertable_schema | TEXT | Schema name of the hypertable |
hypertable_name | TEXT | Table name of the hypertable |
attname | TEXT | Name of the column used in the compression settings |
segmentby_column_index | SMALLINT | Position of attname in the compress_segmentby list |
orderby_column_index | SMALLINT | Position of attname in the compress_orderby list |
orderby_asc | BOOLEAN | True if this is used for order by ASC, False for order by DESC |
orderby_nullsfirst | BOOLEAN | True if nulls are ordered first for this column, False if nulls are ordered last |
Sample Usage
CREATE TABLE hypertab (a_col integer, b_col integer, c_col integer, d_col integer, e_col integer);
SELECT table_name FROM create_hypertable('hypertab', 'a_col');
ALTER TABLE hypertab SET (timescaledb.compress, timescaledb.compress_segmentby = 'a_col,b_col',
timescaledb.compress_orderby = 'c_col desc, d_col asc nulls last');
SELECT * FROM timescaledb_information.compression_settings WHERE hypertable_name = 'hypertab';
hypertable_schema | hypertable_name | attname | segmentby_column_index | orderby_column_in
dex | orderby_asc | orderby_nullsfirst
-------------+------------+---------+------------------------+------------------
----+-------------+--------------------
public | hypertab | a_col | 1 |
| |
public | hypertab | b_col | 2 |
| |
public | hypertab | c_col | |
1 | f | t
public | hypertab | d_col | |
2 | t | f
(4 rows)
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