SQLRowCounterDataSource

SQLRowCounterDataSource is a TypeScript class that implements GetDataSource<number> and retrieves counts of rows.

Usage

const dataSource = new SQLRowCounterDataSource(sqlDialect, sqlInterface, 'employee');
// Counting total number of rows
const totalCount = await dataSource.get(new VoidQuery());
// Counting employees of age 18
const count = await dataSource.get(new AgeQuery(18));

This class only implements the get method, as getAll throws a QueryNotSupportedError.

Supported Queries

To count rows, we need to support the following two query types:

  • SQLWhereQuery
  • SQLWherePaginationQuery

Subclasses will define the exact configuration of each action.

Additional Features

Customization of select statement

Similar to RawSQLDataSource use the selectSQL method to override the select statement.

Soft Delete

SQLRowCounterDataSource supports soft deletion of rows counting. To enable it, just call the SQLRowCounterDataSource constructor passing the option true in the softDeleteEnabled option, as well as the name of the column used to store delete_at date.