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| 1 | +# database_schema/inspectors/dm.py |
| 2 | +from sqlalchemy.sql import text |
| 3 | +from sqlalchemy.engine import reflection |
| 4 | +from .base import BaseInspector |
| 5 | +from urllib.parse import quote_plus |
| 6 | + |
| 7 | +class DMInspector(BaseInspector): |
| 8 | + """达梦数据库（DM Database）元数据获取实现 |
| 9 | +
|
| 10 | + 达梦数据库特点： |
| 11 | + 1. 国产数据库，部分兼容 Oracle 语法 |
| 12 | + 2. 使用 dmPython 驱动 |
| 13 | + 3. 默认端口：5236 |
| 14 | + 4. 支持 Schema 概念，类似 Oracle |
| 15 | + 5. 表名和列名默认大写 |
| 16 | + """ |
| 17 | + |
| 18 | + def __init__(self, host: str, port: int, database: str, |
| 19 | + username: str, password: str, schema_name: str = None, **kwargs): |
| 20 | + super().__init__(host, port, database, username, password, schema_name) |
| 21 | + # 达梦 schema 通常与用户名一致，且默认大写 |
| 22 | + # 如果提供了 schema_name，使用它；否则使用用户名 |
| 23 | + self.schema_name = (schema_name or username).upper() |
| 24 | + |
| 25 | + def build_conn_str(self, host: str, port: int, database: str, |
| 26 | + username: str, password: str) -> str: |
| 27 | + """构建达梦数据库连接字符串 |
| 28 | +
|
| 29 | + 达梦连接格式：dm+dmPython://username:password@host:port/?schema=SCHEMANAME |
| 30 | + """ |
| 31 | + encoded_username = quote_plus(username) |
| 32 | + encoded_password = quote_plus(password) |
| 33 | + |
| 34 | + # 达梦数据库连接字符串 |
| 35 | + # 注意：达梦的连接方式类似 Oracle |
| 36 | + return f"dm+dmPython://{encoded_username}:{encoded_password}@{host}:{port}/" |
| 37 | + |
| 38 | + def get_table_names(self, inspector: reflection.Inspector) -> list[str]: |
| 39 | + """获取指定 schema 下的所有表名""" |
| 40 | + return inspector.get_table_names(schema=self.schema_name) |
| 41 | + |
| 42 | + def get_table_comment(self, inspector: reflection.Inspector, |
| 43 | + table_name: str) -> str: |
| 44 | + """获取表注释 |
| 45 | +
|
| 46 | + 达梦使用类似 Oracle 的系统表结构 |
| 47 | + """ |
| 48 | + with self.engine.connect() as conn: |
| 49 | + sql = text(""" |
| 50 | + SELECT COMMENTS |
| 51 | + FROM ALL_TAB_COMMENTS |
| 52 | + WHERE OWNER = :owner |
| 53 | + AND TABLE_NAME = :table_name |
| 54 | + """) |
| 55 | + try: |
| 56 | + result = conn.execute(sql, { |
| 57 | + 'owner': self.schema_name, |
| 58 | + 'table_name': table_name.upper() |
| 59 | + }).scalar() |
| 60 | + return result or "" |
| 61 | + except Exception as e: |
| 62 | + print(f"获取表注释失败 {table_name}: {str(e)}") |
| 63 | + return "" |
| 64 | + |
| 65 | + def get_column_comment(self, inspector: reflection.Inspector, |
| 66 | + table_name: str, column_name: str) -> str: |
| 67 | + """获取列注释""" |
| 68 | + with self.engine.connect() as conn: |
| 69 | + sql = text(""" |
| 70 | + SELECT COMMENTS |
| 71 | + FROM ALL_COL_COMMENTS |
| 72 | + WHERE OWNER = :owner |
| 73 | + AND TABLE_NAME = :table_name |
| 74 | + AND COLUMN_NAME = :column_name |
| 75 | + """) |
| 76 | + try: |
| 77 | + result = conn.execute(sql, { |
| 78 | + 'owner': self.schema_name, |
| 79 | + 'table_name': table_name.upper(), |
| 80 | + 'column_name': column_name.upper() |
| 81 | + }).scalar() |
| 82 | + return result or "" |
| 83 | + except Exception as e: |
| 84 | + print(f"获取列注释失败 {table_name}.{column_name}: {str(e)}") |
| 85 | + return "" |
| 86 | + |
| 87 | + def normalize_type(self, raw_type: str) -> str: |
| 88 | + """标准化达梦数据类型 |
| 89 | +
|
| 90 | + 达梦支持多种数据类型，部分兼容 Oracle |
| 91 | + """ |
| 92 | + # 类型映射表 |
| 93 | + type_map = { |
| 94 | + # 数值类型 |
| 95 | + 'NUMBER': 'NUMERIC', |
| 96 | + 'NUMERIC': 'NUMERIC', |
| 97 | + 'DECIMAL': 'DECIMAL', |
| 98 | + 'INTEGER': 'INTEGER', |
| 99 | + 'INT': 'INTEGER', |
| 100 | + 'BIGINT': 'BIGINT', |
| 101 | + 'SMALLINT': 'SMALLINT', |
| 102 | + 'TINYINT': 'TINYINT', |
| 103 | + 'FLOAT': 'FLOAT', |
| 104 | + 'DOUBLE': 'DOUBLE', |
| 105 | + 'REAL': 'FLOAT', |
| 106 | + |
| 107 | + # 字符串类型 |
| 108 | + 'VARCHAR': 'VARCHAR', |
| 109 | + 'VARCHAR2': 'VARCHAR', |
| 110 | + 'CHAR': 'CHAR', |
| 111 | + 'CHARACTER': 'CHAR', |
| 112 | + 'TEXT': 'TEXT', |
| 113 | + 'CLOB': 'TEXT', |
| 114 | + 'NCHAR': 'NCHAR', |
| 115 | + 'NVARCHAR': 'NVARCHAR', |
| 116 | + 'NVARCHAR2': 'NVARCHAR', |
| 117 | + |
| 118 | + # 日期时间类型 |
| 119 | + 'DATE': 'DATE', |
| 120 | + 'TIME': 'TIME', |
| 121 | + 'TIMESTAMP': 'TIMESTAMP', |
| 122 | + 'DATETIME': 'DATETIME', |
| 123 | + |
| 124 | + # 二进制类型 |
| 125 | + 'BLOB': 'BLOB', |
| 126 | + 'BINARY': 'BINARY', |
| 127 | + 'VARBINARY': 'VARBINARY', |
| 128 | + 'IMAGE': 'BLOB', |
| 129 | + |
| 130 | + # 其他类型 |
| 131 | + 'BIT': 'BOOLEAN', |
| 132 | + 'BOOLEAN': 'BOOLEAN' |
| 133 | + } |
| 134 | + |
| 135 | + # 提取基础类型（去除长度、精度等） |
| 136 | + base_type = raw_type.split('(')[0].strip().upper() |
| 137 | + |
| 138 | + # 返回标准化类型 |
| 139 | + return type_map.get(base_type, base_type) |
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