Sign inTry Free

Columnstore Table Considerations

Warning

SingleStore 9.0 gives you the opportunity to preview, evaluate, and provide feedback on new and upcoming features prior to their general availability. In the interim, SingleStore 8.9 is recommended for production workloads, which can later be upgraded to SingleStore 9.0.

Columnstore tables (in MemSQL 4.1 and above) have a hidden rowstore table that buffers small inserts into the columnstore table in memory. When enough rows have accumulated in memory, the rows are removed from memory and converted to columnstore format in batch and pushed to disk. The memory use for this hidden rowstore table will show up the same way as a regular rowstore table.

Columnstore tables also store metadata about the files stored on disk in memory. Each file has a row stored in memory with some information about this file (max and min value of the column in this file, bitmap of rows that are deleted, etc.). The memory use for columnstore metadata is currently not broken out into a separate component, but it is included as rowstore memory use along with all other rowstore tables because metadata tables are implemented as hidden rowstore tables. The memory use for columnstore metadata should be small unless the columns are storing large values (the max and min value will be large in this case).

Last modified: April 26, 2021

Was this article helpful?

Was this article helpful?

Verification instructions

Note: You must install cosign to verify the authenticity of the SingleStore file.

Use the following steps to verify the authenticity of singlestoredb-server, singlestoredb-toolbox, singlestoredb-studio, and singlestore-client SingleStore files that have been downloaded.

You may perform the following steps on any computer that can run cosign, such as the main deployment host of the cluster.

  1. (Optional) Run the following command to view the associated signature files.

    curl undefined

  2. Download the signature file from the SingleStore release server.

    • Option 1: Click the Download Signature button next to the SingleStore file.

    • Option 2: Copy and paste the following URL into the address bar of your browser and save the signature file.

    • Option 3: Run the following command to download the signature file.

      curl -O undefined

  3. After the signature file has been downloaded, run the following command to verify the authenticity of the SingleStore file.

    echo -n undefined |
        cosign verify-blob --certificate-oidc-issuer https://oidc.eks.us-east-1.amazonaws.com/id/CCDCDBA1379A5596AB5B2E46DCA385BC \
          --certificate-identity https://kubernetes.io/namespaces/freya-production/serviceaccounts/job-worker \
          --bundle undefined \
          --new-bundle-format -
    Verified OK