TimeScale Notes

TimeScale Compression

Check Distinct Values

---

-- n_distinct (-1 = Unique, 1 = All The Same) SELECT tablename, attname, most_common_vals, most_common_freqs, n_distinct FROM pg_stats -- WHERE tablename = '<TableName>'; WHERE schemaname = '<SchemaName>';

Compress Table

ALTER TABLE crypto_ticks SET (timescaledb.compress,

    timescaledb.compress_segmentby='symbol', 
    timescaledb.compress_orderby='time DESC');

SELECT compress_chunk(c) from show_chunks('crypto_ticks') c;

Check Compression

---

SELECT pg_size_pretty(before_compression_total_bytes) as before,

      pg_size_pretty(after_compression_total_bytes) as after
 FROM hypertable_compression_stats('crypto_ticks');

Compression Policy

---

SELECT add_compression_policy('crypto_ticks', INTERVAL '8 days');

https://docs.timescale.com/tutorials/latest/financial-tick-data/financial-tick-compress/

HyperCore: Since version 2.18.0

          https://docs.timescale.com/use-timescale/latest/compression/ (Old)

https://docs.timescale.com/use-timescale/latest/hypercore/ (New)