例如SELECT 列名1, 列名2 FROM 表名ORDER BY 列名1 DESC, 列名2 ASC 就是从表中查询出列名1安降序排列,查询出列名2安升序排列 insert into 语句用于向表格中插入新的行。 insert into 表名称 (列1, 列2,...) VALUES (值1, 值2,...) insert into 表名称 VALUES (值1, 值2,...) Update 语句 U...
inster into 表名 values() 1. 2. 3. 4. 5. 查询 all():查询所有,返回列表 User.query.all() sql: select .. from tb1 1. 2. 3. fitst():查询第一个,返回对象 User.query.first() sql: select .. from tb1 limit 1 1. 2. 3. get():根据主键id获取对象,主键不存在返回None User.query...
ins = user.insert().values(id=1, name='小明')print(str(ins)) 到此仅仅只是创建了一个inset语句,还没有真正执行呢,接下来执行插入操作: connection = engine.connect() result = connection.execute(ins)print(result.inserted_primary_key) 2.3、查询数据 构建查询时,要用到select函数,它类似于标准SQL S...
from sqlalchemy import select from sqlalchemy.orm import Session session = Session(engine, future=True) # query from a class statement = select(User).filter_by(name="ed") # list of first element of each row (i.e. User objects) result = session.execute(statement).scalars().all() # qu...
all() print(len(res)) # 4.2 取一个 all了后是list,list 没有first方法 res = session.query(User).first() print(res) # 4.3 查询所有,使用占位符(了解) :value :name # select * from user where id <20 or name=lqz099 res = session.query(User).filter(text("id<:value or name=:name...
from sqlalchemy import create_engineengine = create_engine("postgresql+psycopg2://scott:tiger@localhost/test")connection = engine.connect()trans = connection.begin()connection.execute(text("insert into x (a, b) values (1, 2)"))trans.commit() ...
from sqlalchemy.orm import Bundle class DictBundle(Bundle): def create_row_processor(self, query, procs, labels): 'Override create_row_processor to return values as dictionaries' def proc(row): return dict( zip(labels, (proc(row) for proc in procs)) ) return proc...
批量更新 mysql更新语句很简单,更新一条数据的某个字段,一般这样写: UPDATE mytable SET myfield = 'value' WHERE other_field = 'other_value...'); 这里注意 ‘other_values' 是一个逗号(,)分隔的字符串,如:1,2,3 那如果更新多条数据为不同的值,可能很多人会这样写: foreach ($display_order as ...
-- 方式一 SELECT ym_user.*,ym_user_info.* FROM ym_user, ym_user_info WHERE ym_user.id = ym_user_info.uid AND ym_user.id < 50 -- 方式二 SELECT ym_user.*,ym_user_info.* FROM ym_user INNER JOIN ym_user_info ON ym_user.id = ym_user_info.uid WHERE ym_user.id < 50 -...
(date text, trans text, symbol text, qty real, price real)''') # Insert a row of data cur.execute("INSERT INTO stocks VALUES ('2006-01-05','BUY','RHAT',100,35.14)") # Save (commit) the changes con.commit() # Do this instead t = ('RHAT',) cur.execute('SELECT * FROM ...