create_hg_maxcompute_foreign_table

Create foreign tables in Hologres to query MaxCompute data directly, enabling faster analytics without data movement.

Instructions

Create a MaxCompute foreign table in Hologres database to accelerate queries on MaxCompute data.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`maxcompute_project`	Yes	The MaxCompute project name (required)
`maxcompute_schema`	No	The MaxCompute schema name (optional, default: 'default')	default
`maxcompute_tables`	Yes	The MaxCompute table names (required)
`local_schema`	No	The local schema name in Hologres (optional, default: 'public')	public

Implementation Reference

src/hologres_mcp_server/server.py:600-614 (handler)

Handler for create_hg_maxcompute_foreign_table: extracts parameters from arguments, validates required fields, constructs the IMPORT FOREIGN SCHEMA SQL statement, and sets it for execution by handle_call_tool.

elif name == "create_hg_maxcompute_foreign_table":
    maxcompute_project = arguments.get("maxcompute_project")
    maxcompute_schema = arguments.get("maxcompute_schema", "default")
    maxcompute_tables = arguments.get("maxcompute_tables")
    local_schema = arguments.get("local_schema", "public")
    if not all([maxcompute_project, maxcompute_tables]):
        raise ValueError("maxcompute_project and maxcompute_tables are required")
    maxcompute_table_list = ", ".join(maxcompute_tables)
    # 修复 SQL 语句，确保正确拼接项目名称和 schema
    query = f"""
        IMPORT FOREIGN SCHEMA "{maxcompute_project}#{maxcompute_schema}"
        LIMIT TO ({maxcompute_table_list})
        FROM SERVER odps_server
        INTO {local_schema};
    """

src/hologres_mcp_server/server.py:474-500 (schema)

Input schema defining the parameters for the create_hg_maxcompute_foreign_table tool, including required MaxCompute project and tables, optional schema and local schema.

inputSchema={
    "type": "object",
    "properties": {
        "maxcompute_project": {
            "type": "string",
            "description": "The MaxCompute project name (required)"
        },
        "maxcompute_schema": {
            "type": "string",
            "default": "default",
            "description": "The MaxCompute schema name (optional, default: 'default')"
        },
        "maxcompute_tables": {
            "type": "array",
            "items": {
                "type": "string"
            },
            "description": "The MaxCompute table names (required)"
        },
        "local_schema": {
            "type": "string",
            "default": "public",
            "description": "The local schema name in Hologres (optional, default: 'public')"
        }
    },
    "required": ["maxcompute_project", "maxcompute_tables"]
}

src/hologres_mcp_server/server.py:471-501 (registration)

Registration of the create_hg_maxcompute_foreign_table tool in the MCP server's list_tools() function.

Tool(
    name="create_hg_maxcompute_foreign_table",
    description="Create a MaxCompute foreign table in Hologres database to accelerate queries on MaxCompute data.",
    inputSchema={
        "type": "object",
        "properties": {
            "maxcompute_project": {
                "type": "string",
                "description": "The MaxCompute project name (required)"
            },
            "maxcompute_schema": {
                "type": "string",
                "default": "default",
                "description": "The MaxCompute schema name (optional, default: 'default')"
            },
            "maxcompute_tables": {
                "type": "array",
                "items": {
                    "type": "string"
                },
                "description": "The MaxCompute table names (required)"
            },
            "local_schema": {
                "type": "string",
                "default": "public",
                "description": "The local schema name in Hologres (optional, default: 'public')"
            }
        },
        "required": ["maxcompute_project", "maxcompute_tables"]
    }
),

src/hologres_mcp_server/utils.py:48-79 (helper)

Generic helper function used by all tools to execute the SQL query on the Hologres database connection, handling SELECT results and DDL/DML success messages.

def handle_call_tool(tool_name, query, serverless = False):
    """Handle callTool method."""
    config = get_db_config()
    try:
        with connect_with_retry() as conn:
            with conn.cursor() as cursor:

                # 特殊处理 serverless computing 查询
                if serverless:
                    cursor.execute("set hg_computing_resource='serverless'")
                
                # Execute the query
                cursor.execute(query)
                
                # 特殊处理 ANALYZE 命令
                if tool_name == "gather_hg_table_statistics":
                    return f"Successfully {query}"
                
                # 处理其他有返回结果的查询
                if cursor.description:  # SELECT query
                    columns = [desc[0] for desc in cursor.description]
                    rows = cursor.fetchall()
                    result = [",".join(map(str, row)) for row in rows]
                    return "\n".join([",".join(columns)] + result)
                elif tool_name == "execute_dml_sql":  # Non-SELECT query
                    row_count = cursor.rowcount
                    return f"Query executed successfully. {row_count} rows affected."
                else:
                    return "Query executed successfully"
    except Exception as e:
        return f"Error executing query: {str(e)}"

Hologres MCP Server