@probitas/client-sql-duckdb

DuckDB client for Probitas scenario testing framework.

This package provides a DuckDB client designed for integration testing, with analytical query capabilities and Parquet/CSV file support.

Features

• Query Execution: Parameterized queries with type-safe results
• Transactions: Full transaction support
• File Formats: Native support for Parquet, CSV, and JSON files
• In-Memory Databases: Perfect for isolated test scenarios
• Analytical Queries: Optimized for OLAP workloads
• Resource Management: Implements AsyncDisposable for proper cleanup

Installation

deno add jsr:@probitas/client-sql-duckdb

Quick Start

import { createDuckDbClient } from "@probitas/client-sql-duckdb";

// In-memory database for testing
const client = await createDuckDbClient({
  path: ":memory:",
});

// Query from Parquet files
const result = await client.query<{ id: number; name: string }>(
  "SELECT id, name FROM read_parquet('data/*.parquet') WHERE active = ?",
  [true]
);
console.log(result.rows);

// Analytical queries
const stats = await client.query(`
  SELECT
    date_trunc('month', created_at) as month,
    COUNT(*) as count,
    AVG(amount) as avg_amount
  FROM transactions
  GROUP BY 1
  ORDER BY 1
`);

await client.close();

Transactions

await client.transaction(async (tx) => {
  await tx.query("INSERT INTO accounts (id, balance) VALUES (?, ?)", [1, 100]);
  await tx.query("INSERT INTO accounts (id, balance) VALUES (?, ?)", [2, 200]);
  // Automatically committed if no error, rolled back on exception
});

Using with using Statement

await using client = await createDuckDbClient({ path: ":memory:" });

const result = await client.query("SELECT 42 as answer");
// Client automatically closed when block exits

Related Packages

Package	Description
@probitas/client-sql	Common SQL types and utilities
@probitas/client-sql-postgres	PostgreSQL client
@probitas/client-sql-mysql	MySQL client
@probitas/client-sql-sqlite	SQLite client

Links

• GitHub Repository
• Probitas Framework
• DuckDB

deno add jsr:@probitas/client-sql-duckdb

class CatalogError extends DuckDbError

new CatalogError(message: string, options?: DuckDbErrorOptions)

class ConstraintError extends SqlError

new ConstraintError(message: string, constraint: string, options?: SqlErrorOptions)

class DeadlockError extends SqlError

new DeadlockError(message: string, options?: SqlErrorOptions)

class DuckDbError extends SqlError

new DuckDbError(message: string, options?: DuckDbErrorOptions)

class DuckDbTransactionImpl implements SqlTransaction

new DuckDbTransactionImpl(conn: DuckDBConnection)

static begin(): unknown

query(): unknown

queryOne(): unknown

commit(): unknown

rollback(): unknown

class IoError extends DuckDbError

new IoError(message: string, options?: DuckDbErrorOptions)

class QuerySyntaxError extends SqlError

new QuerySyntaxError(message: string, options?: SqlErrorOptions)

class SqlError extends ClientError

new SqlError(message: string, kind: SqlErrorKind, options?: SqlErrorOptions)

class SqlQueryResult<T = Record<string, any>>

new SqlQueryResult(init: SqlQueryResultInit<T>)

map(): unknown

as(): unknown

class SqlRows<T> extends Array<T>

new SqlRows(items: readonly T[])

first(): unknown

firstOrThrow(): unknown

last(): unknown

lastOrThrow(): unknown

interface DuckDbClient extends AsyncDisposable

query<T = Record<string, any>>(sql: string, params?: unknown[]): Promise<SqlQueryResult<T>>

queryOne<T = Record<string, any>>(sql: string, params?: unknown[]): Promise<T | undefined>

transaction<T>(fn: (tx: SqlTransaction) => unknown, options?: SqlTransactionOptions | DuckDbTransactionOptions): Promise<T>

queryParquet<T = Record<string, any>>(path: string): Promise<SqlQueryResult<T>>

queryCsv<T = Record<string, any>>(path: string): Promise<SqlQueryResult<T>>

close(): Promise<void>

interface DuckDbClientConfig extends CommonOptions

interface DuckDbErrorOptions extends SqlErrorOptions

interface DuckDbTransactionOptions extends SqlTransactionOptions

interface SqlErrorOptions extends ErrorOptions

interface SqlQueryResultExpectation<T>

ok(): this

notOk(): this

noContent(): this

hasContent(): this

rows(count: number): this

rowsAtLeast(count: number): this

rowsAtMost(count: number): this

rowCount(count: number): this

rowCountAtLeast(count: number): this

rowCountAtMost(count: number): this

rowContains(subset: Partial<T>): this

rowMatch(matcher: (rows: SqlRows<T>) => unknown): this

mapContains<U>(mapper: (row: T) => unknown, subset: Partial<U>): this

mapMatch<U>(mapper: (row: T) => unknown, matcher: (mapped: U[]) => unknown): this

asContains<U>(ctor: (row: T) => unknown, subset: Partial<U>): this

asMatch<U>(ctor: (row: T) => unknown, matcher: (instances: U[]) => unknown): this

lastInsertId(expected: bigint | string): this

hasLastInsertId(): this

durationLessThan(ms: number): this

interface SqlQueryResultInit<T>

interface SqlQueryResultMetadata

interface SqlTransaction

query<T = Record<string, any>>(sql: string, params?: unknown[]): Promise<SqlQueryResult<T>>

queryOne<T = Record<string, any>>(sql: string, params?: unknown[]): Promise<T | undefined>

commit(): Promise<void>

rollback(): Promise<void>

interface SqlTransactionOptions

function convertDuckDbError(error: unknown): SqlError

async function createDuckDbClient(config: DuckDbClientConfig): Promise<DuckDbClient>

const client = await createDuckDbClient({});

const result = await client.query("SELECT 42 as answer");
console.log(result.rows.first());  // { answer: 42 }

await client.close();

const client = await createDuckDbClient({
  path: "./data.duckdb",
});

// No need to import - query directly from Parquet
const result = await client.queryParquet<{ id: number; value: string }>(
  "./data/events.parquet"
);

const result = await client.queryCsv<{ name: string; age: number }>(
  "./data/users.csv"
);

await client.transaction(async (tx) => {
  await tx.query("INSERT INTO users VALUES ($1, $2)", [1, "Alice"]);
  await tx.query("INSERT INTO users VALUES ($1, $2)", [2, "Bob"]);
});

await using client = await createDuckDbClient({});

const result = await client.query("SELECT 1");
// Client automatically closed when scope exits

function expectSqlQueryResult<T = Record<string, any>>(result: SqlQueryResult<T>): SqlQueryResultExpectation<T>

type DuckDbErrorKind = "io" | "catalog" | "parser" | "binder"

type SqlErrorKind = "query" | "constraint" | "deadlock" | "unknown"

type SqlIsolationLevel = "read_uncommitted" | "read_committed" | "repeatable_read" | "serializable"