537 lines
32 KiB
TypeScript
537 lines
32 KiB
TypeScript
import { AsyncCallerParams } from "@langchain/core/utils/async_caller";
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import { Client, DseClientOptions, types as driverTypes } from "cassandra-driver";
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/**
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* Defines the configuration options for connecting to Astra DB, DataStax's cloud-native Cassandra-as-a-Service.
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* This interface specifies the necessary parameters required to establish a connection with an Astra DB instance,
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* including authentication and targeting specific data centers or regions.
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*
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* Properties:
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* - `token`: The authentication token required for accessing the Astra DB instance. Essential for establishing a secure connection.
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* - `endpoint`: Optional. The URL or network address of the Astra DB instance. Can be used to directly specify the connection endpoint.
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* - `datacenterID`: Optional. The unique identifier of the data center to connect to. Used to compute the endpoint.
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* - `regionName`: Optional. The region name of the Astra DB instance. Used to compute the endpoint. Default to the primary region.
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* - `bundleUrlTemplate`: Optional. The URL template for downloading the secure connect bundle. Used to customize the bundle URL. "database_id" variable will be resolved at runtime.
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*
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* Either `endpoint` or `datacenterID` must be provided to establish a connection to Astra DB.
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*/
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export interface AstraServiceProviderArgs {
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token: string;
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endpoint?: string | URL;
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datacenterID?: string;
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regionName?: string;
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bundleUrlTemplate?: string;
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}
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/**
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* Encapsulates the service provider-specific arguments required for creating a Cassandra client.
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* This interface acts as a wrapper for configurations pertaining to various Cassandra service providers,
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* allowing for extensible and flexible client configuration.
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*
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* Currently, it supports:
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* - `astra`: Optional. Configuration parameters specific to Astra DB, DataStax's cloud-native Cassandra service.
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* Utilizing this property enables tailored connections to Astra DB instances with custom configurations.
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*
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* This structure is designed to be extended with additional service providers in the future, ensuring adaptability
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* and extensibility for connecting to various Cassandra services with distinct configuration requirements.
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*/
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export interface CassandraServiceProviderArgs {
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astra?: AstraServiceProviderArgs;
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}
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/**
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* Extends the DataStax driver's client options with additional configurations for service providers,
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* enabling the customization of Cassandra client instances based on specific service requirements.
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* This interface integrates native driver configurations with custom extensions, facilitating the
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* connection to Cassandra databases, including managed services like Astra DB.
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*
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* - `serviceProviderArgs`: Optional. Contains the connection arguments for specific Cassandra service providers,
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* such as Astra DB. This allows for detailed and service-specific client configurations,
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* enhancing connectivity and functionality across different Cassandra environments.
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*
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* Incorporating this interface into client creation processes ensures a comprehensive setup, encompassing both
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* standard and extended options for robust and versatile Cassandra database interactions.
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*/
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export interface CassandraClientArgs extends DseClientOptions {
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serviceProviderArgs?: CassandraServiceProviderArgs;
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}
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/**
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* Provides a centralized and streamlined factory for creating and configuring instances of the Cassandra client.
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* This class abstracts the complexities involved in instantiating and configuring Cassandra client instances,
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* enabling straightforward integration with Cassandra databases. It supports customization through various
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* configuration options, allowing for the creation of clients tailored to specific needs, such as connecting
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* to different clusters or utilizing specialized authentication and connection options.
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*
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* Key Features:
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* - Simplifies the Cassandra client creation process with method-based configurations.
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* - Supports customization for connecting to various Cassandra environments, including cloud-based services like Astra.
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* - Ensures consistent and optimal client configuration, incorporating best practices.
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*
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* Example Usage (Apache Cassandra®):
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* ```
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* const cassandraArgs = {
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* contactPoints: ['h1', 'h2'],
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* localDataCenter: 'datacenter1',
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* credentials: {
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* username: <...> as string,
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* password: <...> as string,
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* },
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* };
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* const cassandraClient = CassandraClientFactory.getClient(cassandraArgs);
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* ```
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*
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* Example Usage (DataStax AstraDB):
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* ```
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* const astraArgs = {
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* serviceProviderArgs: {
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* astra: {
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* token: <...> as string,
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* endpoint: <...> as string,
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* },
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* },
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* };
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* const cassandraClient = CassandraClientFactory.getClient(astraArgs);
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* ``` *
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*/
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export declare class CassandraClientFactory {
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/**
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* Asynchronously obtains a configured Cassandra client based on the provided arguments.
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* This method processes the given CassandraClientArgs to produce a configured Client instance
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* from the cassandra-driver, suitable for interacting with Cassandra databases.
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*
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* @param args The configuration arguments for the Cassandra client, including any service provider-specific options.
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* @returns A Promise resolving to a Client object configured according to the specified arguments.
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*/
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static getClient(args: CassandraClientArgs): Promise<Client>;
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/**
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* Processes the provided CassandraClientArgs for creating a Cassandra client.
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*
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* @param args The arguments for creating the Cassandra client, including service provider configurations.
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* @returns A Promise resolving to the processed CassandraClientArgs, ready for client initialization.
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* @throws Error if the configuration is unsupported, specifically if serviceProviderArgs are provided
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* but do not include valid configurations for Astra.
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*/
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private static processArgs;
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/**
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* Asynchronously processes and validates the Astra service provider arguments within the
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* Cassandra client configuration. This includes ensuring the presence of necessary Astra
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* configurations like endpoint or datacenterID, setting up default secure connect bundle paths,
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* and initializing default credentials if not provided.
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*
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* @param args The arguments for creating the Cassandra client with Astra configurations.
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* @returns A Promise resolving to the modified CassandraClientArgs with Astra configurations processed.
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* @throws Error if Astra configuration is incomplete or if both endpoint and datacenterID are missing.
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*/
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private static processAstraArgs;
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/**
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* Get the default bundle filesystem location for the Astra Secure Connect Bundle.
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*
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* @param astraArgs The Astra service provider arguments.
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* @returns The default bundle file path.
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*/
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private static getAstraDefaultBundleLocation;
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/**
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* Ensures the Astra secure connect bundle specified by the path exists and is up to date.
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* If the file does not exist or is deemed outdated (more than 360 days old), a new secure
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* connect bundle is downloaded and saved to the specified path.
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*
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* @param astraArgs The Astra service provider arguments, including the datacenterID and optional regionName.
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* @param scbPath The path (or URL) where the secure connect bundle is expected to be located.
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* @returns A Promise that resolves when the secure connect bundle is verified or updated successfully.
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* @throws Error if the bundle cannot be retrieved or saved to the specified path.
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*/
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private static setAstraBundle;
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/**
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* Downloads the Astra secure connect bundle based on the provided Astra service provider arguments
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* and saves it to the specified file path. If a regionName is specified and matches one of the
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* available bundles, the regional bundle is preferred. Otherwise, the first available bundle URL is used.
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*
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* @param astraArgs - The Astra service provider arguments, including datacenterID and optional regionName.
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* @param scbPath - The file path where the secure connect bundle should be saved.
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* @returns A promise that resolves once the secure connect bundle is successfully downloaded and saved.
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* @throws Error if there's an issue retrieving the bundle URLs or saving the bundle to the file path.
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*/
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private static downloadAstraSecureConnectBundle;
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}
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/**
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* Represents the definition of a column within a Cassandra table schema.
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* This interface is used to specify the properties of table columns during table creation
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* and to define how columns are utilized in select queries.
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*
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* Properties:
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* - `name`: The name of the column.
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* - `type`: The data type of the column, used during table creation to define the schema.
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* - `partition`: Optional. Specifies whether the column is part of the partition key. Important for table creation.
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* - `alias`: Optional. An alias for the column that can be used in select queries for readability or to avoid naming conflicts.
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* - `binds`: Optional. Specifies values to be bound to the column in queries, supporting parameterized query construction.
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*
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*/
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export interface Column {
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name: string;
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type: string;
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partition?: boolean;
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alias?: string;
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binds?: unknown | [unknown, ...unknown[]];
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}
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/**
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* Defines an index on a Cassandra table column, facilitating efficient querying by column values.
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* This interface specifies the necessary configuration for creating secondary indexes on table columns,
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* enhancing query performance and flexibility.
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*
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* Properties:
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* - `name`: The name of the index. Typically related to the column it indexes for clarity.
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* - `value`: The name of the column on which the index is created.
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* - `options`: Optional. Custom options for the index, specified as a string. This can include various index
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* configurations supported by Cassandra, such as using specific indexing classes or options.
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*
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*/
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export interface Index {
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name: string;
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value: string;
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options?: string;
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}
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/**
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* Represents a filter condition used in constructing WHERE clauses for querying Cassandra tables.
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* Filters specify the criteria used to select rows from a table, based on column values.
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*
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* Properties:
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* - `name`: The name of the column to filter on.
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* - `value`: The value(s) to match against the column. Can be a single value or an array of values for operations like IN.
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* - `operator`: Optional. The comparison operator to use (e.g., '=', '<', '>', 'IN'). Defaults to '=' if not specified.
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*
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*/
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export interface Filter {
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name: string;
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value: unknown | [unknown, ...unknown[]];
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operator?: string;
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}
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/**
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* Defines a type for specifying WHERE clause conditions in Cassandra queries.
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* This can be a single `Filter` object, an array of `Filter` objects for multiple conditions,
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* or a `Record<string, unknown>` for simple equality conditions keyed by column name.
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*/
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export type WhereClause = Filter[] | Filter | Record<string, unknown>;
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/**
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* Defines the configuration arguments for initializing a Cassandra table within an application.
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* This interface extends `AsyncCallerParams`, incorporating asynchronous operation configurations,
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* and adds specific properties for table creation, query execution, and data manipulation in a
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* Cassandra database context.
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*
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* Properties:
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* - `table`: The name of the table to be used or created.
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* - `keyspace`: The keyspace within which the table exists or will be created.
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* - `primaryKey`: Specifies the column(s) that constitute the primary key of the table. This can be a single
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* `Column` object for a simple primary key or an array of `Column` objects for composite keys.
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* - `nonKeyColumns`: Defines columns that are not part of the primary key. Similar to `primaryKey`, this can be a
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* single `Column` object or an array of `Column` objects, supporting flexible table schema definitions.
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* - `withClause`: Optional. A string containing additional CQL table options to be included in the CREATE TABLE statement.
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* This enables the specification of various table behaviors and properties, such as compaction strategies
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* and TTL settings.
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* - `indices`: Optional. An array of `Index` objects defining secondary indices on the table for improved query performance
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* on non-primary key columns.
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* - `batchSize`: Optional. Specifies the default size of batches for batched write operations to the table, affecting
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* performance and consistency trade-offs.
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*
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*/
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export interface CassandraTableArgs extends AsyncCallerParams {
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table: string;
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keyspace: string;
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primaryKey: Column | Column[];
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nonKeyColumns: Column | Column[];
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withClause?: string;
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indices?: Index[];
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batchSize?: number;
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}
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/**
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* Represents a Cassandra table, encapsulating functionality for schema definition, data manipulation, and querying.
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* This class provides a high-level abstraction over Cassandra's table operations, including creating tables,
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* inserting, updating, selecting, and deleting records. It leverages the CassandraClient for executing
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* operations and supports asynchronous interactions with the database.
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*
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* Key features include:
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* - Table and keyspace management: Allows for specifying table schema, including primary keys, columns,
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* and indices, and handles the creation of these elements within the specified keyspace.
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* - Data manipulation: Offers methods for inserting (upserting) and deleting data in batches or individually,
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* with support for asynchronous operation and concurrency control.
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* - Querying: Enables selecting data with flexible filtering, sorting, and pagination options.
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*
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* The class is designed to be instantiated with a set of configuration arguments (`CassandraTableArgs`)
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* that define the table's structure and operational parameters, providing a streamlined interface for
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* interacting with Cassandra tables in a structured and efficient manner.
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*
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* Usage Example:
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* ```typescript
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* const tableArgs: CassandraTableArgs = {
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* table: 'my_table',
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* keyspace: 'my_keyspace',
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* primaryKey: [{ name: 'id', type: 'uuid', partition: true }],
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* nonKeyColumns: [{ name: 'data', type: 'text' }],
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* };
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* const cassandraClient = new CassandraClient(clientConfig);
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* const myTable = new CassandraTable(tableArgs, cassandraClient);
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* ```
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*
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* This class simplifies Cassandra database interactions, making it easier to perform robust data operations
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* while maintaining clear separation of concerns and promoting code reusability.
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*/
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export declare class CassandraTable {
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private client;
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private readonly keyspace;
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private readonly table;
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private primaryKey;
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private nonKeyColumns;
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private indices;
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private withClause;
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private batchSize;
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private initializationPromise;
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private asyncCaller;
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private constructorArgs;
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/**
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* Initializes a new instance of the CassandraTable class with specified configuration.
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* This includes setting up the table schema (primary key, columns, and indices) and
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* preparing the environment for executing queries against a Cassandra database.
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*
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* @param args Configuration arguments defining the table schema and operational settings.
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* @param client Optional. A Cassandra Client instance. If not provided, one will be created
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* using the configuration specified in `args`.
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*/
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constructor(args: CassandraTableArgs, client?: Client);
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/**
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* Executes a SELECT query on the Cassandra table with optional filtering, ordering, and pagination.
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* Allows for specifying columns to return, filter conditions, sort order, and limits on the number of results.
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*
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* @param columns Optional. Columns to include in the result set. If omitted, all columns are selected.
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* @param filter Optional. Conditions to apply to the query for filtering results.
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* @param orderBy Optional. Criteria to sort the result set.
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* @param limit Optional. Maximum number of records to return.
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* @param allowFiltering Optional. Enables ALLOW FILTERING option for queries that cannot be executed directly due to Cassandra's query restrictions.
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* @param fetchSize Optional. The number of rows to fetch per page (for pagination).
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* @param pagingState Optional. The paging state from a previous query execution, used for pagination.
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* @returns A Promise resolving to the query result set.
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*/
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select(columns?: Column[], filter?: WhereClause, orderBy?: Filter[], limit?: number, allowFiltering?: boolean, fetchSize?: number, pagingState?: string): Promise<driverTypes.ResultSet>;
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/**
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* Validates the correspondence between provided values and specified columns for database operations.
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* This method checks if the number of values matches the number of specified columns, ensuring
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* data integrity before executing insert or update operations. It also defaults to using all table columns
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* if specific columns are not provided. Throws an error if the validation fails.
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*
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* @param values An array of values or an array of arrays of values to be inserted or updated. Each
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* inner array represents a set of values corresponding to one row in the table.
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* @param columns Optional. An array of `Column` objects specifying the columns to be used for the operation.
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* If not provided, the method defaults to using both primary key and non-key columns of the table.
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* @returns An array of `Column` objects that have been validated for the operation.
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* @throws Error if the number of provided values does not match the number of specified columns.
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* @private
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*/
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private _columnCheck;
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/**
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* Inserts or updates records in the Cassandra table in batches, managing concurrency and batching size.
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* This method organizes the provided values into batches and uses `_upsert` to perform the database operations.
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*
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* @param values An array of arrays, where each inner array contains values for a single record.
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* @param columns Optional. Columns to be included in the insert/update operations. Defaults to all table columns.
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* @param batchSize Optional. The size of each batch for the operation. Defaults to the class's batchSize property.
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* @returns A Promise that resolves once all records have been upserted.
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*/
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upsert(values: unknown[][], columns?: Column[], batchSize?: number): Promise<void>;
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/**
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* Deletes rows from the Cassandra table that match the specified WHERE clause conditions.
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*
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* @param whereClause Defines the conditions that must be met for rows to be deleted. Can be a single filter,
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* an array of filters, or a key-value map translating to filter conditions.
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* @returns A Promise that resolves when the DELETE operation has completed.
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*/
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delete(whereClause: WhereClause): Promise<driverTypes.ResultSet>;
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/**
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* Retrieves the Node.js Cassandra client instance associated with this table.
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* This method ensures that the client is initialized and ready for use, returning the
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* Cassandra client object that can be used for database operations directly.
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* It initializes the client if it has not already been initialized.
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*
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* @returns A Promise that resolves to the Cassandra Client instance used by this table for database interactions.
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*/
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getClient(): Promise<Client>;
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/**
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* Constructs the PRIMARY KEY clause for a Cassandra CREATE TABLE statement based on the specified columns.
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* This method organizes the provided columns into partition and clustering keys, forming the necessary syntax
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* for the PRIMARY KEY clause in a Cassandra table schema definition. It supports complex primary key structures,
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* including composite partition keys and clustering columns.
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*
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* - Partition columns are those marked with the `partition` property. If multiple partition columns are provided,
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* they are grouped together in parentheses as a composite partition key.
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* - Clustering columns are those not marked as partition keys and are listed after the partition key(s).
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* They determine the sort order of rows within a partition.
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*
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* The method ensures the correct syntax for primary keys, handling both simple and composite key structures,
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* and throws an error if no partition or clustering columns are provided.
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*
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* @param columns An array of `Column` objects representing the columns to be included in the primary key.
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* Each column must have a `name` and may have a `partition` boolean indicating if it is part
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* of the partition key.
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* @returns The PRIMARY KEY clause as a string, ready to be included in a CREATE TABLE statement.
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* @throws Error if no columns are marked as partition keys or if no columns are provided.
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* @private
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*/
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private buildPrimaryKey;
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/**
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* Type guard that checks if a given object conforms to the `Filter` interface.
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* This method is used to determine if an object can be treated as a filter for Cassandra
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* query conditions. It evaluates the object's structure, specifically looking for `name`
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* and `value` properties, which are essential for defining a filter in Cassandra queries.
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*
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* @param obj The object to be evaluated.
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* @returns A boolean value indicating whether the object is a `Filter`. Returns `true`
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* if the object has both `name` and `value` properties, signifying it meets the
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* criteria for being used as a filter in database operations; otherwise, returns `false`.
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* @private
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*/
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private isFilter;
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/**
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* Helper to convert Record<string,unknown> to a Filter[]
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* @param record: a key-value Record collection
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* @returns Record as a Filter[]
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*/
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private convertToFilters;
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/**
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* Converts a key-value pair record into an array of `Filter` objects suitable for Cassandra query conditions.
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* This utility method allows for a more flexible specification of filter conditions by transforming
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* a simple object notation into the structured format expected by Cassandra query builders. Each key-value
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* pair in the record is interpreted as a filter condition, where the key represents the column name and
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* the value represents the filtering criterion.
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*
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* The method assumes a default equality operator for each filter. It is particularly useful for
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* converting concise filter specifications into the detailed format required for constructing CQL queries.
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*
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* @param record A key-value pair object where each entry represents a filter condition, with the key
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* as the column name and the value as the filter value. The value can be a single value
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* or an array to support IN queries with multiple criteria.
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* @returns An array of `Filter` objects, each representing a condition extracted from the input record.
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* The array can be directly used in constructing query WHERE clauses.
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* @private
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*/
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private asFilters;
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/**
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* Constructs the WHERE clause of a CQL query from an array of `Filter` objects.
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* This method generates the conditional part of a Cassandra Query Language (CQL) statement,
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* allowing for complex query constructions based on provided filters. Each filter in the array
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* translates into a condition within the WHERE clause, with support for various comparison operators.
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*
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* The method handles the assembly of these conditions into a syntactically correct CQL WHERE clause,
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* including the appropriate use of placeholders (?) for parameter binding in prepared statements.
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* It supports a range of operators, defaulting to "=" (equality) if an operator is not explicitly specified
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* in a filter. Filters with multiple values (e.g., for IN conditions) are also correctly formatted.
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*
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* @param filters Optional. An array of `Filter` objects representing the conditions to apply in the WHERE clause.
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* Each `Filter` includes a column name (`name`), a value or array of values (`value`), and optionally,
|
|
* an operator (`operator`). If no filters are provided, an empty string is returned.
|
|
* @returns The constructed WHERE clause as a string, ready to be appended to a CQL query. If no filters
|
|
* are provided, returns an empty string, indicating no WHERE clause should be applied.
|
|
* @private
|
|
*/
|
|
private buildWhereClause;
|
|
/**
|
|
* Generates the ORDER BY clause for a CQL query from an array of `Filter` objects.
|
|
* This method forms the sorting part of a Cassandra Query Language (CQL) statement,
|
|
* allowing for detailed control over the order of results based on specified column names
|
|
* and directions. Each filter in the array represents a column and direction to sort by.
|
|
*
|
|
* It is important to note that unlike the traditional use of `Filter` objects for filtering,
|
|
* in this context, they are repurposed to specify sorting criteria. The `name` field indicates
|
|
* the column to sort by, and the `operator` field is used to specify the sort direction (`ASC` or `DESC`).
|
|
* The `value` field is not utilized for constructing the ORDER BY clause and can be omitted.
|
|
*
|
|
* @param filters Optional. An array of `Filter` objects where each object specifies a column and
|
|
* direction for sorting. The `name` field of each filter represents the column name,
|
|
* and the `operator` field should contain the sorting direction (`ASC` or `DESC`).
|
|
* If no filters are provided, the method returns an empty string.
|
|
* @returns The constructed ORDER BY clause as a string, suitable for appending to a CQL query.
|
|
* If no sorting criteria are provided, returns an empty string, indicating no ORDER BY
|
|
* clause should be applied to the query.
|
|
* @private
|
|
*/
|
|
private buildOrderByClause;
|
|
/**
|
|
* Constructs a CQL search query string for retrieving records from a Cassandra table.
|
|
* This method combines various query components, including selected columns, filters, sorting criteria,
|
|
* and pagination options, to form a complete and executable CQL query. It allows for fine-grained control
|
|
* over the query construction process, enabling the inclusion of conditional filtering, ordering of results,
|
|
* and limiting the number of returned records, with an optional allowance for filtering.
|
|
*
|
|
* The method meticulously constructs the SELECT part of the query using the provided columns, applies
|
|
* the WHERE clause based on given filters, sorts the result set according to the orderBy criteria, and
|
|
* restricts the number of results with the limit parameter. Additionally, it can enable the ALLOW FILTERING
|
|
* option for queries that require server-side filtering beyond the capabilities of primary and secondary indexes.
|
|
*
|
|
* @param queryColumns An array of `Column` objects specifying which columns to include in the result set.
|
|
* Each column can also have an alias defined for use in the query's result set.
|
|
* @param filters Optional. An array of `Filter` objects to apply as conditions in the WHERE clause of the query.
|
|
* @param orderBy Optional. An array of `Filter` objects specifying the ordering of the returned records.
|
|
* Although repurposed as `Filter` objects, here they define the column names and the sort direction (ASC/DESC).
|
|
* @param limit Optional. A numeric value specifying the maximum number of records the query should return.
|
|
* @param allowFiltering Optional. A boolean flag that, when true, includes the ALLOW FILTERING clause in the query,
|
|
* permitting Cassandra to execute queries that might not be efficiently indexable.
|
|
* @returns A string representing the fully constructed CQL search query, ready for execution against a Cassandra table.
|
|
* @private
|
|
*/
|
|
private buildSearchQuery;
|
|
/**
|
|
* Initializes the CassandraTable instance, ensuring it is ready for database operations.
|
|
* This method is responsible for setting up the internal Cassandra client, creating the table
|
|
* if it does not already exist, and preparing any indices as specified in the table configuration.
|
|
* The initialization process is performed only once; subsequent calls return the result of the
|
|
* initial setup. If a Cassandra `Client` instance is provided, it is used directly; otherwise,
|
|
* a new client is created based on the table's configuration.
|
|
*
|
|
* The initialization includes:
|
|
* - Assigning the provided or newly created Cassandra client to the internal client property.
|
|
* - Executing a CQL statement to create the table with the specified columns, primary key, and
|
|
* any additional options provided in the `withClause`.
|
|
* - Creating any custom indices as defined in the table's indices array.
|
|
*
|
|
* This method leverages the asynchronous nature of JavaScript to perform potentially time-consuming
|
|
* tasks, such as network requests to the Cassandra cluster, without blocking the execution thread.
|
|
*
|
|
* @param client Optional. A `Client` instance from the cassandra-driver package. If provided, this client
|
|
* is used for all database operations performed by the instance. Otherwise, a new client
|
|
* is instantiated based on the configuration provided at the CassandraTable instance creation.
|
|
* @returns A Promise that resolves once the initialization process has completed, indicating the instance
|
|
* is ready for database operations. If initialization has already occurred, the method returns
|
|
* immediately without repeating the setup process.
|
|
* @private
|
|
*/
|
|
private initialize;
|
|
/**
|
|
* Performs the actual initialization tasks for the CassandraTable instance.
|
|
* This method is invoked by the `initialize` method to carry out the concrete steps necessary for preparing
|
|
* the CassandraTable instance for operation. It includes establishing the Cassandra client (either by utilizing
|
|
* an existing client passed as a parameter or by creating a new one based on the instance's configuration),
|
|
* and executing the required CQL statements to create the table and its indices according to the specifications
|
|
* provided during the instance's creation.
|
|
*
|
|
* The process encapsulates:
|
|
* 1. Assigning the provided Cassandra `Client` to the instance, or creating a new one if none is provided.
|
|
* 2. Creating the table with the specified schema if it does not exist. This involves constructing a CQL
|
|
* `CREATE TABLE` statement that includes columns, primary key configuration, and any specified table options.
|
|
* 3. Creating any indices specified in the instance's configuration using CQL `CREATE INDEX` statements, allowing
|
|
* for custom index options if provided.
|
|
*
|
|
* This method ensures that the table and its environment are correctly set up for subsequent database operations,
|
|
* encapsulating initialization logic to maintain separation of concerns and improve code readability and maintainability.
|
|
*
|
|
* @param client Optional. An instance of the Cassandra `Client` from the cassandra-driver package. If provided,
|
|
* this client is used for all interactions with the Cassandra database. If not provided, a new client
|
|
* is instantiated based on the provided configuration during the CassandraTable instance creation.
|
|
* @returns A Promise that resolves when all initialization steps have been successfully completed, indicating
|
|
* that the CassandraTable instance is fully prepared for database operations.
|
|
* @private
|
|
*/
|
|
private performInitialization;
|
|
/**
|
|
* Performs the actual insert or update operation (upsert) on the Cassandra table for a batch of values.
|
|
* This method constructs and executes a CQL INSERT statement for each value in the batch.
|
|
*
|
|
* @param values An array of arrays, where each inner array contains values corresponding to the specified columns.
|
|
* @param columns Optional. Specifies the columns into which the values should be inserted. Defaults to all columns.
|
|
* @returns A Promise that resolves when the operation has completed.
|
|
* @private
|
|
*/
|
|
private _upsert;
|
|
}
|