create_hg_maxcompute_foreign_table

Instructions

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)}"