Peewee 简明教程

Peewee - Select Records

从表中检索数据的最简单也是最明显的方法是调用相应模型的 select() 方法。在 select() 方法内部,我们可以指定一个或多个字段属性。但是,如果没有指定,则会选择所有列。

Simplest and the most obvious way to retrieve data from tables is to call select() method of corresponding model. Inside select() method, we can specify one or more field attributes. However, if none is specified, all columns are selected.

Model.select() 返回与行对应的模型实例列表。这类似于 SELECT 查询返回的结果集,可以通过 for 循环遍历该结果集。

Model.select() returns a list of model instances corresponding to rows. This is similar to the result set returned by SELECT query, which can be traversed by a for loop.

from peewee import *
db = SqliteDatabase('mydatabase.db')
class User (Model):
   name=TextField()
   age=IntegerField()
   class Meta:
      database=db
      db_table='User'
rows=User.select()
print (rows.sql())
for row in rows:
   print ("name: {} age: {}".format(row.name, row.age))
db.close()

上述脚本显示以下输出 -

The above script displays the following output −

('SELECT "t1"."id", "t1"."name", "t1"."age" FROM "User" AS "t1"', [])
name: Rajesh age: 21
name: Amar age  : 20
name: Kiran age : 19
name: Lata age  : 20