UNPKG

@langchain/community

Version:
187 lines (186 loc) 9.48 kB
import type { EmbeddingsInterface } from "@langchain/core/embeddings"; import { VectorStore, MaxMarginalRelevanceSearchOptions } from "@langchain/core/vectorstores"; import { Document } from "@langchain/core/documents"; export type DistanceStrategy = "euclidean" | "cosine"; interface Filter { [key: string]: boolean | string | number; } /** * Interface defining the arguments required to create an instance of * `HanaDB`. */ export interface HanaDBArgs { connection: any; distanceStrategy?: DistanceStrategy; tableName?: string; contentColumn?: string; metadataColumn?: string; vectorColumn?: string; vectorColumnLength?: number; } export declare class HanaDB extends VectorStore { private connection; private distanceStrategy; private static compiledPattern; private tableName; private contentColumn; private metadataColumn; private vectorColumn; private vectorColumnLength; FilterType: Filter; _vectorstoreType(): string; constructor(embeddings: EmbeddingsInterface, args: HanaDBArgs); private executeQuery; private prepareQuery; private executeStatement; initialize(): Promise<void>; /** * Sanitizes the input string by removing characters that are not alphanumeric or underscores. * @param inputStr The string to be sanitized. * @returns The sanitized string. */ static sanitizeName(inputStr: string): string; /** * Sanitizes the input to integer. Throws an error if the value is less than -1. * @param inputInt The input to be sanitized. * @returns The sanitized integer. */ static sanitizeInt(inputInt: any): number; /** * Sanitizes a list to ensure all elements are floats (numbers in TypeScript). * Throws an error if any element is not a number. * * @param {number[]} embedding - The array of numbers (floats) to be sanitized. * @returns {number[]} The sanitized array of numbers (floats). * @throws {Error} Throws an error if any element is not a number. */ static sanitizeListFloat(embedding: number[]): number[]; /** * Sanitizes the keys of the metadata object to ensure they match the required pattern. * Throws an error if any key does not match the pattern. * * @param {Record<string, any>} metadata - The metadata object with keys to be validated. * @returns {object[] | object} The original metadata object if all keys are valid. * @throws {Error} Throws an error if any metadata key is invalid. */ private sanitizeMetadataKeys; /** * Parses a string representation of a float array and returns an array of numbers. * @param {string} arrayAsString - The string representation of the array. * @returns {number[]} An array of floats parsed from the string. */ static parseFloatArrayFromString(arrayAsString: string): number[]; /** * Checks if the specified column exists in the table and validates its data type and length. * @param tableName The name of the table. * @param columnName The name of the column to check. * @param columnType The expected data type(s) of the column. * @param columnLength The expected length of the column. Optional. */ checkColumn(tableName: string, columnName: string, columnType: string | string[], columnLength?: number): Promise<void>; private createTableIfNotExists; tableExists(tableName: string): Promise<boolean>; /** * Creates a WHERE clause based on the provided filter object. * @param filter - A filter object with keys as metadata fields and values as filter values. * @returns A tuple containing the WHERE clause string and an array of query parameters. */ private createWhereByFilter; /** * Deletes entries from the table based on the provided filter. * @param ids - Optional. Deletion by ids is not supported and will throw an error. * @param filter - Optional. A filter object to specify which entries to delete. * @throws Error if 'ids' parameter is provided, as deletion by ids is not supported. * @throws Error if 'filter' parameter is not provided, as it is required for deletion. * to do: adjust the call signature */ delete(options: { ids?: string[]; filter?: Filter; }): Promise<void>; /** * Static method to create a HanaDB instance from raw texts. This method embeds the documents, * creates a table if it does not exist, and adds the documents to the table. * @param texts Array of text documents to add. * @param metadatas metadata for each text document. * @param embedding EmbeddingsInterface instance for document embedding. * @param dbConfig Configuration for the HanaDB. * @returns A Promise that resolves to an instance of HanaDB. */ static fromTexts(texts: string[], metadatas: object[] | object, embeddings: EmbeddingsInterface, dbConfig: HanaDBArgs): Promise<HanaDB>; /** * Creates an instance of `HanaDB` from an array of * Document instances. The documents are added to the database. * @param docs List of documents to be converted to vectors. * @param embeddings Embeddings instance used to convert the documents to vectors. * @param dbConfig Configuration for the HanaDB. * @returns Promise that resolves to an instance of `HanaDB`. */ static fromDocuments(docs: Document[], embeddings: EmbeddingsInterface, dbConfig: HanaDBArgs): Promise<HanaDB>; /** * Adds an array of documents to the table. The documents are first * converted to vectors using the `embedDocuments` method of the * `embeddings` instance. * @param documents Array of Document instances to be added to the table. * @returns Promise that resolves when the documents are added. */ addDocuments(documents: Document[]): Promise<void>; /** * Adds an array of vectors and corresponding documents to the database. * The vectors and documents are batch inserted into the database. * @param vectors Array of vectors to be added to the table. * @param documents Array of Document instances corresponding to the vectors. * @returns Promise that resolves when the vectors and documents are added. */ addVectors(vectors: number[][], documents: Document[]): Promise<void>; /** * Return docs most similar to query. * @param query Query text for the similarity search. * @param k Number of Documents to return. Defaults to 4. * @param filter A dictionary of metadata fields and values to filter by. Defaults to None. * @returns Promise that resolves to a list of documents and their corresponding similarity scores. */ similaritySearch(query: string, k: number, filter?: Filter): Promise<Document[]>; /** * Return documents and score values most similar to query. * @param query Query text for the similarity search. * @param k Number of Documents to return. Defaults to 4. * @param filter A dictionary of metadata fields and values to filter by. Defaults to None. * @returns Promise that resolves to a list of documents and their corresponding similarity scores. */ similaritySearchWithScore(query: string, k: number, filter?: Filter): Promise<[Document, number][]>; /** * Return docs most similar to the given embedding. * @param query Query embedding for the similarity search. * @param k Number of Documents to return. Defaults to 4. * @param filter A dictionary of metadata fields and values to filter by. Defaults to None. * @returns Promise that resolves to a list of documents and their corresponding similarity scores. */ similaritySearchVectorWithScore(queryEmbedding: number[], k: number, filter?: Filter): Promise<[Document, number][]>; /** * Performs a similarity search based on vector comparison and returns documents along with their similarity scores and vectors. * @param embedding The vector representation of the query for similarity comparison. * @param k The number of top similar documents to return. * @param filter Optional filter criteria to apply to the search query. * @returns A promise that resolves to an array of tuples, each containing a Document, its similarity score, and its vector. */ similaritySearchWithScoreAndVectorByVector(embedding: number[], k: number, filter?: Filter): Promise<Array<[Document, number, number[]]>>; /** * Return documents selected using the maximal marginal relevance. * Maximal marginal relevance optimizes for similarity to the query AND * diversity among selected documents. * @param query Text to look up documents similar to. * @param options.k Number of documents to return. * @param options.fetchK=20 Number of documents to fetch before passing to * the MMR algorithm. * @param options.lambda=0.5 Number between 0 and 1 that determines the * degree of diversity among the results, where 0 corresponds to maximum * diversity and 1 to minimum diversity. * @returns List of documents selected by maximal marginal relevance. */ maxMarginalRelevanceSearch(query: string, options: MaxMarginalRelevanceSearchOptions<this["FilterType"]>): Promise<Document[]>; } export {};