Configuration and Extensions

def get_core_config():
    """
    Get set of core DuckDB configuration parameters.
    
    Retrieves all available DuckDB settings from the database plus
    MotherDuck-specific configuration keys for cloud connectivity.
    
    Returns:
    Set[str]: Set of configuration parameter names including:
        - All DuckDB settings from duckdb_settings()
        - MotherDuck parameters: motherduck_token, attach_mode, saas_mode
    """

def apply_config(dialect, conn, ext):
    """
    Apply configuration settings to DuckDB connection.
    
    Processes configuration parameters and applies them as DuckDB SET
    statements with proper type handling and SQL escaping.
    
    Parameters:
    - dialect (Dialect): SQLAlchemy dialect instance for processing
    - conn (DuckDBPyConnection): DuckDB connection to configure  
    - ext (Dict[str, Union[str, int, bool]]): Configuration parameters
    
    Raises:
    AssertionError: If configuration value type is not supported
    """

TYPES: Dict[Type, TypeEngine]
"""
Maps Python types to SQLAlchemy type processors for configuration.

Supported types:
- int -> Integer()
- str -> String() 
- bool -> Boolean()
"""

def has_comment_support():
    """
    Check if current DuckDB version supports table comments.
    
    Tests COMMENT ON TABLE functionality by attempting to create
    a test table and add a comment.
    
    Returns:
    bool: True if comments supported, False otherwise
    """

has_uhugeint_support: bool
"""Boolean flag indicating if DuckDB version supports UHUGEINT type (v0.10.0+)."""

duckdb_version: Version
"""Parsed version object for current DuckDB installation."""

engine = create_engine('duckdb:///:memory:', connect_args={
    'config': {
        'threads': 4,
        'memory_limit': '2GB',
        'max_memory': '4GB',
        'default_order': 'ASC',
        'enable_progress_bar': True,
        'enable_profiling': 'json',
        'profile_output': '/tmp/profile.json'
    }
})

engine = create_engine('duckdb:///:memory:', connect_args={
    'preload_extensions': ['spatial', 'json', 'httpfs', 'parquet']
})

import fsspec

# Create custom filesystem
fs = fsspec.filesystem('s3', key='access_key', secret='secret_key')

engine = create_engine('duckdb:///:memory:', connect_args={
    'register_filesystems': [fs]
})

engine = create_engine('duckdb:///', connect_args={
    'config': {
        'motherduck_token': 'your_token_here',
        'attach_mode': 'auto',
        'saas_mode': True
    }
})

engine = create_engine('duckdb:///:memory:', connect_args={
    'config': {
        'custom_user_agent': 'MyApp/1.0'
    }
})

from sqlalchemy import create_engine

# Configure DuckDB with performance settings
engine = create_engine('duckdb:///data.db', connect_args={
    'config': {
        'threads': 8,
        'memory_limit': '8GB',
        'enable_progress_bar': True
    }
})

import fsspec
from sqlalchemy import create_engine

# Setup S3 filesystem
s3_fs = fsspec.filesystem('s3', 
    key='your_access_key',
    secret='your_secret_key'
)

engine = create_engine('duckdb:///analytics.db', connect_args={
    'preload_extensions': ['httpfs', 'spatial', 'json'],
    'register_filesystems': [s3_fs],
    'config': {
        'threads': 4,
        'memory_limit': '4GB',
        's3_region': 'us-west-2'
    }
})

engine = create_engine('duckdb:///', connect_args={
    'config': {
        'motherduck_token': 'your_motherduck_token',
        'attach_mode': 'auto',
        'saas_mode': True,
        'custom_user_agent': 'MyDataApp/2.1'
    }
})

from duckdb_engine.config import get_core_config, apply_config
from duckdb_engine import Dialect
import duckdb

# Get available configuration options
core_configs = get_core_config()
print("Available configs:", core_configs)

# Apply configuration programmatically
dialect = Dialect()
conn = duckdb.connect(':memory:')

config_settings = {
    'threads': 2,
    'memory_limit': '1GB',
    'enable_profiling': 'json'
}

apply_config(dialect, conn, config_settings)

from duckdb_engine._supports import (
    has_comment_support, 
    has_uhugeint_support,
    duckdb_version
)

print(f"DuckDB version: {duckdb_version}")
print(f"Supports comments: {has_comment_support()}")
print(f"Supports UHUGEINT: {has_uhugeint_support}")

# Conditional feature usage
if has_comment_support():
    engine.execute("COMMENT ON TABLE users IS 'User data table'")

# Basic configuration via URL
engine = create_engine(
    'duckdb:///data.db?threads=4&memory_limit=2GB&enable_progress_bar=true'
)

# MotherDuck connection via URL
engine = create_engine(
    'duckdb:///?motherduck_token=your_token&saas_mode=true'
)

from sqlalchemy import create_engine, event

def configure_connection(dbapi_connection, connection_record):
    """Custom connection configuration function."""
    with dbapi_connection.cursor() as cursor:
        cursor.execute("SET enable_profiling = 'json'")
        cursor.execute("SET profile_output = '/tmp/queries.json'")

engine = create_engine('duckdb:///data.db')

# Apply configuration after connection
event.listen(engine, 'connect', configure_connection)