Structures

A structure representing metadata for a collection in the database.

This metadata includes the collection’s name, the indexes associated with it, and the partition key used for organizing the data.

• Properties:
• name: The name of the collection.
• indexes: An array of strings representing the indexes defined for the collection.
• partitionKey: The key used to partition the data within the collection.

A structure that represents metrics for an index, providing insights into its usage and value distribution.

• Properties:
  • accessCount: The number of times the index has been accessed. Defaults to 0.
  • lastAccess: The date and time when the index was last accessed. Defaults to .distantPast.
  • valueDistribution: A dictionary that tracks the distribution of values associated with the index, where the keys are the values and the values are their respective counts. Defaults to an empty dictionary.

A generic structure representing a query for a specific type of data.

This structure is used to build and execute queries on a collection of data stored in a database. It supports filtering data using predicates and key path predicates, and relies on a storage engine and query planner for execution.

• Properties:

  • collection: The name of the collection being queried.
  • predicates: A list of field-based predicates used to filter the data.
  • storage: The storage engine responsible for managing the data.
  • planner: The query planner responsible for optimizing and executing the query.
  • keyPathPredicates: A list of key path-based predicates used to filter the data.

A structure representing the execution plan for a query in the database.

The ExecutionPlan provides details about how a query will be executed, including the collection being queried, the predicates applied, the estimated number of documents to scan, and the index strategy used.

• Properties:

  • collection: The name of the collection being queried.
  • predicates: An array of tuples representing the query predicates, where each tuple contains a field name and a query operator.
  • estimatedDocsToScan: The estimated number of documents that will be scanned during the query execution.
  • shardsToSkip: The number of shards that can be skipped during query execution.
  • usedIndex: The name of the index used for the query, if any. If no index is used, this will be nil.
  • indexStrategy: The strategy used for indexing during query execution.

• Conforms to:

  • CustomStringConvertible: Provides a human-readable description of the execution plan.

A structure responsible for planning and optimizing database queries.

QueryPlanner provides statistical information about indexes and shards to assist in query execution planning.

• Properties:
  • indexStats: A dictionary containing statistics for each index, where the key is the index name and the value is an IndexStat object.
  • shardStats: An array of ShardStat objects representing statistics for each shard in the database.

A structure that represents metadata for a shard in the database.

ShardMetadata contains information about the shard, such as the number of documents it holds, and timestamps for when it was created and last updated.

• Properties:
  • documentCount: The total number of documents stored in the shard.
  • createdAt: The date and time when the shard was created.
  • updatedAt: The date and time when the shard was last updated.

A structure representing metadata information for a shard.

ShardMetadataInfo contains details about a specific shard, including its unique identifier, its location as a URL, and its associated metadata.

• Properties:
  • id: A unique identifier for the shard.
  • url: The URL location of the shard.
  • metadata: The metadata associated with the shard.

A structure representing statistics for a collection in the database.

CollectionStats provides detailed information about a specific collection, including its name, the number of shards, the total number of documents, the total size in bytes, and metadata about each shard.

• Properties:
  • collectionName: The name of the collection.
  • numberOfShards: The number of shards associated with the collection.
  • totalDocuments: The total number of documents stored in the collection.
  • totalSizeInBytes: The total size of the collection in bytes.
  • shardDetails: An array of metadata information for each shard.

A structure representing global statistics for the database.

GlobalStats provides an overview of the database’s state, including the total number of collections, documents, and the total size in bytes.

• Properties:
  • totalCollections: The total number of collections in the database.
  • totalDocuments: The total number of documents across all collections.
  • totalSizeInBytes: The total size of the database in bytes.

A structure representing statistical information about an index.

This structure provides details about the total number of entries, the count of unique values, the distribution of values, and access-related metadata for an index.

• Properties:
  • totalCount: The total number of entries in the index.
  • uniqueValuesCount: The number of unique values in the index.
  • valueDistribution: A dictionary mapping each unique value to its occurrence count.
  • accessCount: The number of times the index has been accessed.
  • lastAccess: The date and time when the index was last accessed.

Represents statistics for a shard in the database.

• Properties:
  • docCount: The total number of documents in the shard.
  • fieldRanges: A dictionary mapping field names to their respective minimum and maximum values. The values are represented as AnyHashable to allow for flexibility in data types.