August 2018
Intermediate to advanced
230 pages
6h 42m
Chinese
Content preview from Flask Web开发：基于Python的Web应用开发实战（第2版）
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数据库
｜
49
类型名 Python类型 说 明
BigInteger
int
或
long
不限制精度的整数
Float float
浮点数
Numeric decimal.Decimal
定点数
String str
变长字符串
Text str
变长字符串，对较长或不限长度的字符串做了优化
Unicode unicode
变长
Unicode
字符串
UnicodeText unicode
变长
Unicode
字符串，对较长或不限长度的字符串
做了优化
Boolean bool
布尔值
Date datetime.date
日期
Time datetime.time
时间
DateTime datetime.datetime
日期和时间
Interval datetime.timedelta
时间间隔
Enum str
一组字符串
PickleType
任何
Python
对象 自动使用
Pickle
序列化
LargeBinary str
二进制
blob
db.Column
的其余参数指定属性的配置选项。表
5-3
列出了一些可用选项。
表5-3：最常用的SQLAlchemy列选项
选项名 说 明
primary_key
如果设为
True
，列为表的主键
unique
如果设为
True
，列不允许出现重复的值
index
如果设为
True
，为列创建索引，提升查询效率
nullable
如果设为
True
，列允许使用空值；如果设为
False
，列不允许使用空值
default
为列定义默认值
Flask-SQLAlchemy
要求每个模型都定义
主键
，这一列经常命名为
id
。
虽然没有强制要求，但这两个模型都定义了 ...
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.