refactor: The first refactored version for sdk release (#907)

Co-authored-by: chengfangyin2 <chengfangyin3@jd.com>

dbgpt/datasource/rdbms/conn_mssql.py

@@ -0,0 +1,47 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+from typing import Optional, Any, Iterable
+
+from sqlalchemy import (
+    MetaData,
+    Table,
+    create_engine,
+    inspect,
+    select,
+    text,
+)
+from dbgpt.datasource.rdbms.base import RDBMSDatabase
+
+
+class MSSQLConnect(RDBMSDatabase):
+    """Connect MSSQL Database fetch MetaData
+    Args:
+    Usage:
+    """
+
+    db_type: str = "mssql"
+    db_dialect: str = "mssql"
+    driver: str = "mssql+pymssql"
+
+    default_db = ["master", "model", "msdb", "tempdb", "modeldb", "resource", "sys"]
+
+    def table_simple_info(self) -> Iterable[str]:
+        _tables_sql = f"""
+                SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE='BASE TABLE'
+            """
+        cursor = self.session.execute(text(_tables_sql))
+        tables_results = cursor.fetchall()
+        results = []
+        for row in tables_results:
+            table_name = row[0]
+            _sql = f"""
+                SELECT COLUMN_NAME, DATA_TYPE FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME='{table_name}'
+            """
+            cursor_colums = self.session.execute(text(_sql))
+            colum_results = cursor_colums.fetchall()
+            table_colums = []
+            for row_col in colum_results:
+                field_info = list(row_col)
+                table_colums.append(field_info[0])
+            results.append(f"{table_name}({','.join(table_colums)});")
+        return results