update (select debt+pay_way as pay , pay_id from brick.pay_map) b inner join brick.pay_info a on a.pay_id = b.pay_id set a.need_pay=b.pay ;
update set from where时 “from“ is not valid at this position ,expecting EOF,“;“ (表中两字段运算结果赋值给另一个表的字段)
***from处显示显示from is not valid at this***
About This Book
Develop a strong
set
of programm
ing
skills with Pyhton that you will be able to express in any situation, on every platform, thanks to Python's portability
Stop writ
ing
scripts and start architect
ing
programs by apply
ing
object-oriented programm
ing
techniques in Python
Learn the trickier aspects of Python and put it in a structured context for deeper understand
ing
of the language
Who This Book Is For
This course is meant for programmers who wants to learn Python programm
ing
from a basic to an expert level. The course is mostly self-contained and introduces Python programm
ing
to a new reader and can help him become an expert in this trade.
What You Will Learn
Get Python up and runn
ing
on Windows, Mac, and Linux in no time
Grasp the fundamental concepts of cod
ing
, along with the basics of data structures and control flow
Understand when to use the functional or the object-oriented programm
ing
approach
Extend class functionality us
ing
inheritance
Exploit object-oriented programm
ing
in key Python technologies, such as Kivy and Django
Understand how and when to use the functional programm
ing
paradigm
Use the multiprocess
ing
library, not just locally but also across multiple machines
In Detail
Python is a dynamic and powerful programm
ing
language, hav
ing
its application in a wide range of domains. It has an easy-to-use, simple syntax, and a powerful library, which includes hundreds of modules to provide routines for a wide range of applications, thus mak
ing
it a popular language among program
ing
enthusiasts.This course will take you on a journey from basic programm
ing
practices to high-end tools and techniques giv
ing
you an edge over your peers. It follows an interest
ing
learn
ing
path, divided into three modules. As you complete each one, you'll have gained key skills and get ready for the material in the next module.The first module will begin with explor
ing
all the essentials of Python programm
ing
in an easy-to-understand way. This will lay a good foundation for those who are interested in digg
ing
deeper. It has a practical and example-oriented approach through which both the introductory and the advanced topics are explained. Start
ing
with the fundamentals of programm
ing
and Python, it ends by explor
ing
topics, like GUIs, web apps, and data science.In the second module you will learn about object oriented programm
ing
techniques in Python. Start
ing
with a detailed analysis of object-oriented technique and design, you will use the Python programm
ing
language to clearly grasp key concepts from the object-oriented paradigm. This module fully explains classes, data encapsulation, inheritance, polymorphism, abstraction, and exceptions with an emphasis on when you can use each principle to develop well-designed software.With a good foundation of Python you will move onto the third module which is a comprehensive tutorial cover
ing
advanced features of the Python language. Start by creat
ing
a project-specific environment us
ing
venv. This will introduce you to various Pythonic syntax and common pitfalls before mov
ing
onto functional features and advanced concepts, thereby gain
ing
an expert level knowledge in programm
ing
and teach
ing
how to script highest quality Python programs.
Style and approach
This course follows a theory-cum-practical approach hav
ing
all the
ing
redients that will help you jump into the field of Python programm
ing
as a novice and grow-up as an expert. The aim is to create a smooth learn
ing
path that will teach you how to get started with Python and carry out expert-level programm
ing
techniques at the end of course.
Table of Contents
Module 1: Learn
ing
Python
Chapter 1: Introduction and First Steps – Take a Deep Breath
Chapter 2: Built-in Data Types
Chapter 3: Iterat
ing
and Mak
ing
Decisions
Chapter 4: Functions, the Build
ing
Blocks of Code
Chapter 5: Sav
ing
Time and Memory
Chapter 6: Advanced Concepts – OOP, Decorators, and Iterators
Chapter 7: Test
ing
, Profil
ing
, and Deal
ing
with Exceptions
Chapter 8: The Edges – GUIs and Scripts
Chapter 9: Data Science
Chapter 10: Web Development Done Right
Chapter 11: Debugg
ing
and Troubleshoot
ing
Chapter 12: Summ
ing
Up – A Complete Example
Module 2: Python 3 Object-Oriented Programm
ing
Chapter 1: Object-oriented Design
Chapter 2: Objects in Python
Chapter 3: When Objects Are Alike
Chapter 4:
Expect
ing
the Un
expected
Chapter 5: When to Use Object-oriented Programm
ing
Chapter 6: Python Data Structures
Chapter 7: Python Object-oriented Shortcuts
Chapter 8: Str
ing
s and Serialization
Chapter 9: The Iterator Pattern
Chapter 10: Python Design Patterns I
Chapter 11: Python Design Patterns II
Chapter 12: Test
ing
Object-oriented Programs
Chapter 13: Concurrency
Module 3: Master
ing
Python
Chapter 1: Gett
ing
Started – One Environment per Project
Chapter 2: Pythonic Syntax, Common Pitfalls, and Style Guide
Chapter 3: Containers and Collections – Stor
ing
Data the Right Way
Chapter 4: Functional Programm
ing
– Readability Versus Brevity
Chapter 5: Decorators – Enabl
ing
Code Reuse by Decorat
ing
Chapter 6: Generators and Coroutines – Infinity, One Step at a Time
Chapter 7: Async IO – Multithread
ing
without Threads
Chapter 8: Metaclasses – Mak
ing
Classes (Not Instances) Smarter
Chapter 9: Documentation – How to Use Sphinx and reStructuredText
Chapter 10: Test
ing
and Logg
ing
– Prepar
ing
for Bugs
Chapter 11: Debugg
ing
– Solv
ing
the Bugs
Chapter 12: Performance – Track
ing
and Reduc
ing
Your Memory and CPU Usage
Chapter 13: Multiprocess
ing
– When a S
ing
le CPU Core Is Not Enough
Chapter 14: Extensions in C/C++, System Calls, and C/C++ Libraries
Chapter 15: Packag
ing
– Creat
ing
Your Own Libraries or Applications
Title: Python: Journey from Novice to Expert
Author: Dusty Phillips, Fabrizio Romano, Rick van Hattem
Length: 1311 pages
Edition: 1
Language: English
Publisher: Packt Publish
ing
Publication Date: 2016-08-31
ISBN-10: B01LD8K8WW
update
movie
set
desc="2021-05-21 08:00~10:00" where key=1就是这么简单的一句更新语句愣是报错了半小
时
,最后才找到原因短短一句话我用了
两
个保留字'desc'、'key',解决办法就是加上反引号``,改成
update
movie
set
`desc`="2021-05-21 08:00~10:00" where `key`=1
select * from cop.student where sdept='CS' intersect select * from cop.student where sage<=19
/*查询计算机科学系的学生与年龄不大于19岁的学生的交集*/
select sno from cop.sc where cno='1' INTERSECT select sno from cop.sc where cno='2';
/*查询选修课程1的学生集合与选修课程2的学生集合的交集*/
打完代码就发现代码