hypertable_compression_stats()
Get statistics related to hypertable compression. All sizes are in bytes.
Required arguments
| Name | Type | Description |
|---|---|---|
hypertable |
REGCLASS | Hypertable to show stats for. |
Returns
| Column | Type | Description |
|---|---|---|
total_chunks |
BIGINT | the number of chunks used by the hypertable |
number_compressed_chunks |
INTEGER | the number of chunks used by the hypertable that are currently compressed |
before_compression_table_bytes |
BIGINT | Size of the heap before compression (NULL if currently uncompressed) |
before_compression_index_bytes |
BIGINT | Size of all the indexes before compression (NULL if currently uncompressed) |
before_compression_toast_bytes |
BIGINT | Size the TOAST table before compression (NULL if currently uncompressed) |
before_compression_total_bytes |
BIGINT | Size of the entire table (table+indexes+toast) before compression (NULL if currently uncompressed) |
after_compression_table_bytes |
BIGINT | Size of the heap after compression (NULL if currently uncompressed) |
after_compression_index_bytes |
BIGINT | Size of all the indexes after compression (NULL if currently uncompressed) |
after_compression_toast_bytes |
BIGINT | Size the TOAST table after compression (NULL if currently uncompressed) |
after_compression_total_bytes |
BIGINT | Size of the entire table (table+indexes+toast) after compression (NULL if currently uncompressed) |
node_name |
TEXT | nodes on which the hypertable is located, applicable only to distributed hypertables |
Sample usage
2. SELECT * FROM hypertable_compression_stats('conditions');
4. -[ RECORD 1 ]------------------+------
6. total_chunks | 4
8. number_compressed_chunks | 1
10. before_compression_table_bytes | 8192
12. before_compression_index_bytes | 32768
14. before_compression_toast_bytes | 0
16. before_compression_total_bytes | 40960
18. after_compression_table_bytes | 8192
20. after_compression_index_bytes | 32768
22. after_compression_toast_bytes | 8192
24. after_compression_total_bytes | 49152
26. node_name |
Use pg_size_pretty get the output in a more human friendly format.
2. SELECT pg_size_pretty(after_compression_total_bytes) as total
4. FROM hypertable_compression_stats('conditions');
6. -[ RECORD 1 ]--+------
8. total | 48 kB
