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Key-Value Store

A key-value collection stores data in the form of a dictionary. This requires a key for each record and a corresponding value that contains the data. Each document in the database must have a unique key, similar to the concept of a primary key. Key-value databases are known for being quick and storage efficient resulting in faster CRUD (Create, Read, Update, Delete) operations.

Key-Value Store Contents​

In GDN, each key-value pair (document) stored in a collection contains a _key, and the rest of the document is its value. The only key-value operations available are key lookups (single and batch) and key-value pair insertions and updates. If no sharding attribute is specified, then _key is used for sharding the data instead.

Key-value collections are always global. You can specify time_to_live (TTL) during creation.

Group ID​

When you create a key-value store collection, you can select the Group option to enable the GROUP ID field. This allows you to organize key-value pairs in groups. This option has several effects:

  • The Group ID field is automatically indexed, which makes querying based on the ID faster.
  • You can perform queries and truncate based on the group ID value.

Here are some example C8QL queries:

FOR d IN <collection> FILTER d.groupID == "<groupID>" RETURN d
FOR d IN <collection> FILTER d.groupID == "<groupID>" RETURN {_key: d._key, value: d.value}

KV Blob Storage​

note

This feature is available upon request. Contact support@macrometa.com to enable it on your account.

If this feature is enabled on your account, then when you create a new key-value store, you can select the Blob storage checkbox. This marks the collection as a blob-based KV collection. These collections can only be used to store blob files, such as images. Once created, this setting cannot be changed.

  • Maximum blob file size is 1 MB. This can be changed, but can never exceed 2 MB.
  • You can add blob records using the Macrometa API. Adding records in the Macrometa web console is not supported.