# 查询information_schema获取列名defget_column_names(table_name):conn=connect_to_database()cursor=conn.cursor()# 构造SQL语句sql=f"SELECT COLUMN_NAME FROM information_schema.COLUMNS WHERE TABLE_NAME = '{table_name}'"# 执行SQL语句cursor.execute(sql)# 获取结果result=cursor.fetchall()# 提取列名co...
#解析sql语句中的字段和表名, 参考 https://www.robin.eu.org/programming/extracting-table-and-column-names-from-sql-query/ def sqlparse(sql_str): sql_str = sql_str.replace('SELECT', 'select') sql_str = sql_str.replace('WHERE', 'where') sql_str = sql_str.replace('FROM', 'from')...
records = pd.read_sql_query('''select cast(date as date) as NaturalDay, symbol from table where date between begin and end’’’) 是一个ast.assign类型,它的一个子节点是ast.call,对应的代码是 pd.read_sql_query('''select cast(date as date) as NaturalDay, symbol from table where date ...
from sqlalchemy import create_engine, MetaData, Column from sqlalchemy.dialects.mysql import INTEGER, DOUBLE, BIGINT, VARCHAR, CHAR, TEXT, DATETIME from sqlalchemy.ext.declarative import declarative_base from sqlalchemy.orm import sessionmaker # 创建数据库引擎,ps:这里并没有连接具体数据库 engine = ...
mysql> insert into stu_info (name,age,register_date) values ("LiuYouyuan",20,"2015-9-1"); Query OK, 1 row affected (0.05 sec) mysql> select * from stu_info; +---+---+---+---+ | stu_id | name | age | register_date | +---+---+---+---+ | 1 | LiuYouyuan | 20...
文本中的代码词、数据库表名、文件夹名、文件名、文件扩展名、路径名、虚拟 URL、用户输入和 Twitter 用户名显示如下:“我们可以通过调用get_data()函数来收集所需的信息。” 代码块设置如下: defhello_world():print(“Hello World!”) hello_world() ...
name, column.type) 二、Python 从数据库读取数据从数据库读取数据是 Python 的另一个重要功能。我们可以使用 SQLAlchemy 的查询功能来执行 SQL 查询并获取结果。以下是一个示例,展示如何从 “users” 表中读取所有用户:2.1 执行查询并获取结果```pythonfrom sqlalchemy.orm import sessionmaker, loadonlyfrom sql...
insp=inspect(engine)insp.get_table_names()[Out:]['apartment','building','student','inspector','manager','managercontact'] 2.1 查看默认数据库的一个表格 fromsqlalchemy.sqlimporttextsql='''SELECT * FROM building;'''withengine.connect().execution_options(autocommit=True)asconn:query=conn.execute...
defget_table_names(self, db_name:str) ->tuple: sql_command ="select distinct(table_name) from INFORMATION_SCHEMA.Columns where table_schema='{0}'".format(db_name) self._cursor.execute(sql_command) query_data = self._cursor.fetchall() ...
SQL -- Query the UDTF with the input table as an argument and a directive to partition the input-- rows such that all rows with each unique value in the `a` column are processed by the same-- instance of the UDTF class. Within each partition, the rows are ordered by the `b` colum...