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querychat (version 0.2.0)

DataSource: Data Source Base Class

Description

An abstract R6 class defining the interface that custom QueryChat data sources must implement. This class should not be instantiated directly; instead, use one of its concrete implementations like DataFrameSource or DBISource.

Arguments

Public fields

table_name

Name of the table to be used in SQL queries

Methods

Method get_db_type()

Get the database type

Usage

DataSource$get_db_type()

Returns

A string describing the database type (e.g., "DuckDB", "SQLite")

Method get_schema()

Get schema information about the table

Usage

DataSource$get_schema(categorical_threshold = 20)

Arguments

categorical_threshold

Maximum number of unique values for a text column to be considered categorical

Returns

A string containing schema information formatted for LLM prompts

Method execute_query()

Execute a SQL query and return results

Usage

DataSource$execute_query(query)

Arguments

query

SQL query string to execute

Returns

A data frame containing query results

Method test_query()

Test a SQL query by fetching only one row

Usage

DataSource$test_query(query, require_all_columns = FALSE)

Arguments

query

SQL query string to test

require_all_columns

If TRUE, validates that the result includes all original table columns (default: FALSE)

Returns

A data frame containing one row of results (or empty if no matches)

Method get_data()

Get the unfiltered data as a data frame

Usage

DataSource$get_data()

Returns

A data frame containing all data from the table

Method cleanup()

Clean up resources (close connections, etc.)

Usage

DataSource$cleanup()

Returns

NULL (invisibly)

Method clone()

The objects of this class are cloneable with this method.

Usage

DataSource$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

Examples

Run this code
MyDataSource <- R6::R6Class(
  "MyDataSource",
  inherit = DataSource,
  public = list(
    initialize = function(table_name) {
      self$table_name <- table_name
    }
    # Implement abstract methods here...
  )
)

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