import pymysqldef get_table_structure(connection, cursor, database, table):# 获取表结构query = f"SHOW COLUMNS FROM {database}.{table}"cursor.execute(query)return cursor.fetchall()def generate_create_table(cursor, table_structure, database, table):# 生成创建表的SQL语句，包含字段约束、默认值和主键信息columns = []for column in table_structure:column_name = column[0]column_type = column[1]is_nullable = "NOT NULL" if column[2] == "NO" else ""default_value = f"DEFAULT {column[4]}" if column[4] is not None else ""columns.append(f"`{column_name}` {column_type} {is_nullable} {default_value}")# 查找主键信息cursor.execute(f"SHOW KEYS FROM {table} WHERE Key_name = 'PRIMARY'")primary_key = cursor.fetchone()if primary_key:columns.append(f"PRIMARY KEY (`{primary_key[4]}`)")return f"CREATE TABLE `{database}`.`{table}` ({', '.join(columns)});"def generate_add_or_modify_column(connection, cursor, database, table, column_structure):# 生成添加字段或修改字段的SQL语句alter_statements = []for column_info in column_structure:# column_name, column_type, is_nullable, default_value = column_info# default_clause = f"DEFAULT {default_value}" if default_value is not None else ""column_name = column_info[0]column_type = column_info[1]is_nullable = "NOT NULL" if column_info[2] == "NO" else ""default_value = f"DEFAULT  {column_info[4]}" if (column_info[4] is not None and column_info[4]) else "DEFAULT NULL"# 检查字段是否已经存在if is_column_exists(cursor, database, table, column_name):# 字段存在，生成修改字段的SQL语句alter_statements.append(f"ALTER TABLE `{database}`.`{table}` MODIFY COLUMN `{column_name}` {column_type} {is_nullable} {default_value} ;")else:# 字段不存在，生成添加字段的SQL语句alter_statements.append(f"ALTER TABLE `{database}`.`{table}` ADD COLUMN `{column_name}` {column_type} {is_nullable} {default_value} ;")return alter_statementsdef is_column_exists(cursor, database, table, column_name):# 检查字段是否存在于目标表中query = f"SHOW COLUMNS FROM `{database}`.`{table}` LIKE '{column_name}'"cursor.execute(query)return cursor.fetchone() is not Noneif __name__ == "__main__":dba ="test";dbb = "test1";# 连接数据库Adb_a = pymysql.connect(host="127.0.0.1", port=3307, user="root", password="123456", database=dba)cursor_a = db_a.cursor()# 连接数据库Bdb_b = pymysql.connect(host="127.0.0.1", port=3307, user="root", password="123456", database=dbb)cursor_b = db_b.cursor()# 获取数据库A中的表cursor_a.execute("SHOW TABLES")database_a_tables = [table[0] for table in cursor_a.fetchall()]# 获取数据库B中的表cursor_b.execute("SHOW TABLES")database_b_tables = [table[0] for table in cursor_b.fetchall()]# 比较两个数据库的表结构并生成SQL语句for table in database_a_tables:if table not in database_b_tables:# 表在库B中缺失，生成创建表语句table_structure = get_table_structure(db_a, cursor_a,dba, table)create_table_sql = generate_create_table(cursor_a, table_structure, dbb, table)print(create_table_sql)else:# 表在库B中存在，比较字段columns_a = get_table_structure(db_a, cursor_a, dba, table)columns_b = get_table_structure(db_b, cursor_b,dbb, table)# 字段差异column_diff = [col for col in columns_a if col not in columns_b]# 生成添加字段或修改字段的SQL语句alter_column_sqls = generate_add_or_modify_column(db_b, cursor_b, dbb, table, column_diff)for alter_column_sql in alter_column_sqls:print(alter_column_sql)# 关闭数据库连接db_a.close()db_b.close()