recompress_chunk()

Recompresses a compressed chunk that had more data inserted after compression.

recompress_chunk(
    chunk REGCLASS,
    if_not_compressed BOOLEAN = false
)

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You can also recompress chunks by running the job associated with your compression policy. recompress_chunk gives you more fine-grained control by allowing you to target a specific chunk.

Important

recompress_chunk is deprecated since version 2.14 and will be removed in the future. The procedure is now a wrapper which calls compress_chunk instead of it.

Important

recompress_chunk is implemented as an SQL procedure and not a function. Call the procedure with CALL. Don't use a SELECT statement.

Note

recompress_chunk only works on chunks that have previously been compressed. To compress a chunk for the first time, use compress_chunk.

Recompress the chunk timescaledb_internal._hyper_1_2_chunk:

CALL recompress_chunk('_timescaledb_internal._hyper_1_2_chunk');

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In TimescaleDB 2.6.0 and above, recompress_chunk is implemented as a procedure. Previously, it was implemented as a function. If you are upgrading to TimescaleDB 2.6.0 or above, therecompress_chunk function could cause an error. For example, trying to run SELECT recompress_chunk(i.show_chunks, true) FROM... gives the following error:

ERROR:  recompress_chunk(regclass, boolean) is a procedure

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To fix the error, use CALL instead of SELECT. You might also need to write a procedure to replace the full functionality in your SELECT statement. For example:

DO $$
DECLARE chunk regclass;
BEGIN
  FOR chunk IN SELECT format('%I.%I', chunk_schema, chunk_name)::regclass
  FROM timescaledb_information.chunks
  WHERE is_compressed = true
  LOOP
    RAISE NOTICE 'Recompressing %', chunk::text;
    CALL recompress_chunk(chunk, true);
  END LOOP;
END
$$;

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