Add Druid quickstarts

.github/data/databases.json

@@ -39,6 +39,10 @@
     "name": "DataFusion",
     "parent": null
   },
+  "druid": {
+    "name": "Apache Druid",
+    "parent": null
+  },
   "doris": {
     "name": "Apache Doris",
     "parent": "flightsql"

README.md

@@ -48,6 +48,7 @@ Simple examples showing how to use ADBC to connect, run a query, and return the
 - [ClickHouse](https://github.com/columnar-tech/adbc-quickstarts/tree/by-database/clickhouse)
 - [Databricks](https://github.com/columnar-tech/adbc-quickstarts/tree/by-database/databricks)
 - [DataFusion](https://github.com/columnar-tech/adbc-quickstarts/tree/by-database/datafusion)
+- [Apache Druid](https://github.com/columnar-tech/adbc-quickstarts/tree/by-database/druid)
 - DuckDB-compatible systems
   - [DuckDB](https://github.com/columnar-tech/adbc-quickstarts/tree/by-database/duckdb)
   - [MotherDuck](https://github.com/columnar-tech/adbc-quickstarts/tree/by-database/motherduck)

cpp/README.md

@@ -32,6 +32,7 @@ Simple C++ examples showing how to use ADBC to connect, run a query, and return
 - [ClickHouse](./clickhouse)
 - [Databricks](./databricks)
 - [DataFusion](./datafusion)
+- [Apache Druid](./druid)
 - [DuckDB-compatible systems](./duckdb)
   - [DuckDB](./duckdb/duckdb)
   - [MotherDuck](./duckdb/motherduck)

cpp/druid/CMakeLists.txt

@@ -0,0 +1,43 @@
+# Copyright 2026 Columnar Technologies Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+cmake_minimum_required(VERSION 3.15)
+project(druid_demo CXX)
+
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+# Use conda environment paths
+if(DEFINED ENV{CONDA_PREFIX})
+    list(APPEND CMAKE_PREFIX_PATH "$ENV{CONDA_PREFIX}")
+endif()
+
+find_package(Arrow REQUIRED)
+
+add_executable(druid_demo main.cpp)
+
+if(DEFINED ENV{CONDA_PREFIX})
+    target_include_directories(druid_demo PRIVATE $ENV{CONDA_PREFIX}/include)
+    target_link_directories(druid_demo PRIVATE $ENV{CONDA_PREFIX}/lib)
+endif()
+
+target_link_libraries(druid_demo
+    adbc_driver_manager
+    Arrow::arrow_shared
+)
+
+target_compile_options(druid_demo PRIVATE
+    -Wall
+    -Werror
+)

cpp/druid/Makefile

@@ -0,0 +1,24 @@
+# Copyright 2026 Columnar Technologies Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+CXXFLAGS = -std=c++17 -Wall -Werror -I$(CONDA_PREFIX)/include
+LIBS = -L$(CONDA_PREFIX)/lib -ladbc_driver_manager -larrow -Wl,-rpath,$(CONDA_PREFIX)/lib
+
+druid_demo: main.cpp
+	$(CXX) $(CXXFLAGS) -o druid_demo main.cpp $(LIBS)
+
+clean:
+	rm -f druid_demo
+
+.PHONY: clean

cpp/druid/README.md

@@ -0,0 +1,101 @@
+<!--
+Copyright 2026 Columnar Technologies Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
+# Connecting C++ and Apache Druid with ADBC
+
+## Instructions
+
+> [!TIP]
+> If you already have a Druid instance running, skip the steps to set up Druid.
+
+### Prerequisites
+
+1. [Install Pixi](https://pixi.prefix.dev/latest/)
+
+1. [Install dbc](https://docs.columnar.tech/dbc/getting_started/installation/)
+
+### Set up Druid
+
+1. [Install Docker](https://docs.docker.com/get-started/get-docker/)
+
+1. Start a Druid 37 nano-quickstart instance:
+
+   ```sh
+   docker run --detach --rm \
+     --name druid \
+     --platform linux/amd64 \
+     --publish 8888:8888 \
+     --volume "$PWD/start-druid.sh:/opt/druid/start-druid.sh:ro" \
+     --entrypoint /bin/bash \
+     apache/druid:37.0.0 /opt/druid/start-druid.sh
+   ```
+
+1. Wait for Druid to accept SQL queries:
+
+   ```sh
+   until curl --fail --silent --output /dev/null \
+     --header 'Content-Type: application/json' \
+     --data '{"query":"SELECT 1"}' \
+     http://localhost:8888/druid/v2/sql; do sleep 2; done
+   ```
+
+### Connect to Druid
+
+1. Install the Druid ADBC driver:
+
+   ```sh
+   dbc install --level user --pre druid
+   ```
+
+1. Customize the C++ program `main.cpp` as needed,
+   - Change the connection arguments in the `AdbcDatabaseSetOption()` calls
+     - Format the URI according to the [driver documentation](https://docs.adbc-drivers.org/drivers/druid/index.html#connecting), or keep it as is
+
+1. Build and run the C++ program:
+
+   Using Make:
+   ```sh
+   pixi run make
+   ./druid_demo
+   ```
+
+   Or using CMake:
+   ```sh
+   pixi run cmake -B build
+   pixi run cmake --build build
+   ./build/druid_demo
+   ```
+
+
+### Clean up
+
+1. Clean build artifacts:
+
+   Using Make:
+   ```sh
+   pixi run make clean
+   ```
+
+   Using CMake:
+   ```sh
+   rm -rf build
+   ```
+
+1. Stop the Docker container running Druid:
+
+   ```sh
+   docker stop druid
+   ```

cpp/druid/main.cpp

@@ -0,0 +1,113 @@
+// Copyright 2026 Columnar Technologies Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// For EXIT_SUCCESS
+#include <cstdlib>
+// For strerror
+#include <cstring>
+#include <iostream>
+
+#include <arrow-adbc/adbc.h>
+#include <arrow-adbc/adbc_driver_manager.h>
+#include <arrow/c/bridge.h>
+#include <arrow/record_batch.h>
+
+// Error-checking helper for ADBC calls.
+// Assumes that there is an AdbcError named `error` in scope.
+#define CHECK_ADBC(EXPR)                                                       \
+  if (AdbcStatusCode status = (EXPR); status != ADBC_STATUS_OK) {              \
+    if (error.message != nullptr) {                                            \
+      std::cerr << error.message << std::endl;                                 \
+    }                                                                          \
+    return EXIT_FAILURE;                                                       \
+  }
+
+// Error-checking helper for ArrowArrayStream.
+#define CHECK_STREAM(STREAM, EXPR)                                             \
+  if (int status = (EXPR); status != 0) {                                      \
+    std::cerr << "(" << std::strerror(status) << "): ";                        \
+    const char *message = (STREAM).get_last_error(&(STREAM));                  \
+    if (message != nullptr) {                                                  \
+      std::cerr << message << std::endl;                                       \
+    } else {                                                                   \
+      std::cerr << "(no error message)" << std::endl;                          \
+    }                                                                          \
+    return EXIT_FAILURE;                                                       \
+  }
+
+int main() {
+  AdbcError error = {};
+
+  AdbcDatabase database = {};
+  CHECK_ADBC(AdbcDatabaseNew(&database, &error));
+
+  CHECK_ADBC(AdbcDatabaseSetOption(&database, "driver", "druid", &error));
+  CHECK_ADBC(AdbcDatabaseSetOption(
+      &database, "uri", "druid://localhost:8888?tls=false", &error));
+  CHECK_ADBC(AdbcDriverManagerDatabaseSetLoadFlags(
+      &database, ADBC_LOAD_FLAG_DEFAULT, &error));
+  CHECK_ADBC(AdbcDatabaseInit(&database, &error));
+
+  AdbcConnection connection = {};
+  CHECK_ADBC(AdbcConnectionNew(&connection, &error));
+  CHECK_ADBC(AdbcConnectionInit(&connection, &database, &error));
+
+  AdbcStatement statement = {};
+  CHECK_ADBC(AdbcStatementNew(&connection, &statement, &error));
+
+  struct ArrowArrayStream stream = {};
+  int64_t rows_affected = -1;
+
+  CHECK_ADBC(AdbcStatementSetSqlQuery(
+      &statement,
+      "SELECT \"server\", server_type, tier, curr_size, max_size "
+      "FROM sys.servers "
+      "ORDER BY server_type, \"server\" "
+      "LIMIT 10",
+      &error));
+  CHECK_ADBC(
+      AdbcStatementExecuteQuery(&statement, &stream, &rows_affected, &error));
+
+  // Import stream as record batch reader
+  auto maybe_reader = arrow::ImportRecordBatchReader(&stream);
+  if (!maybe_reader.ok()) {
+    std::cerr << "Failed to import record batch reader: "
+              << maybe_reader.status().message() << std::endl;
+    return 1;
+  }
+
+  auto reader = maybe_reader.ValueOrDie();
+
+  while (true) {
+    auto maybe_batch = reader->Next();
+    if (!maybe_batch.ok()) {
+      std::cerr << "Error reading batch: " << maybe_batch.status().message()
+                << std::endl;
+      return 1;
+    }
+
+    auto batch = maybe_batch.ValueOrDie();
+    if (!batch) {
+      break;
+    }
+
+    std::cout << batch->ToString() << std::endl;
+  }
+
+  CHECK_ADBC(AdbcStatementRelease(&statement, &error));
+  CHECK_ADBC(AdbcConnectionRelease(&connection, &error));
+  CHECK_ADBC(AdbcDatabaseRelease(&database, &error));
+
+  return EXIT_SUCCESS;
+}

cpp/druid/pixi.toml

@@ -0,0 +1,12 @@
+[workspace]
+channels = ["conda-forge"]
+name = "druid"
+platforms = ["win-64", "linux-64", "osx-64", "osx-arm64"]
+
+[tasks]
+
+[dependencies]
+cmake = ">=4.3.0,<5"
+compilers = ">=1.11.0,<2"
+libadbc-driver-manager = ">=1.10.0,<2"
+libarrow = ">=23.0.1,<24"

cpp/druid/start-druid.sh

@@ -0,0 +1,50 @@
+#!/bin/bash
+# Copyright 2026 Columnar Technologies Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -euo pipefail
+
+readonly config="conf/druid/single-server/nano-quickstart"
+pids=()
+
+start() {
+  "$@" &
+  pids+=("$!")
+}
+
+shutdown() {
+  trap - EXIT INT TERM
+  kill -TERM "${pids[@]}" 2>/dev/null || true
+  wait "${pids[@]}" 2>/dev/null || true
+}
+
+trap shutdown EXIT INT TERM
+
+start bin/run-zk conf
+start bin/run-druid coordinator-overlord "$config"
+start bin/run-druid broker "$config"
+start bin/run-druid router "$config"
+start bin/run-druid historical "$config"
+start bin/run-druid middleManager "$config"
+
+set +e
+wait -n "${pids[@]}"
+status=$?
+set -e
+
+# A service exiting normally still means the container is no longer healthy.
+if [[ $status -eq 0 ]]; then
+  status=1
+fi
+exit "$status"

csharp/README.md

@@ -32,6 +32,7 @@ Simple C# examples showing how to use ADBC to connect, run a query, and return t
 - [ClickHouse](./clickhouse)
 - [Databricks](./databricks)
 - [DataFusion](./datafusion)
+- [Apache Druid](./druid)
 - [DuckDB-compatible systems](./duckdb)
   - [DuckDB](./duckdb/duckdb)
   - [MotherDuck](./duckdb/motherduck)