The basic use and installation of SQLAlchemy no longer repeat, please see the big blog Liao XuefengAttach Portal: Http://www.liaoxuefeng.com/wiki/001374738125095c955c1e6d8bb493182103fac9270762a000/ 0014021031294178f993c85204e4d1b81ab032070641ce5000Below is a summary of the details of using the MySQL environment and SQLAlchemy in the Python environment:
Install the MySQL base dependent environment
| 1, One,9, -,6,5,4,3,2 |
| 2 | Ten, A |
| 3 | 8,7 |
+-------------+---------------------+
3Rowsinch Set(0.00Sec According to the type of equipment, compare the above data, is not all of a sudden all out. But how to use it in SQLAlchemy? SQLAlchemy has a func that contains various SQL functions. Let's try it out. The model of
Very idiotic problem, insert database submission failed, always go integrityerror error, no error message, thought plug in, get a long time, and finally printed the error message(Sqlite3. Integrityerror) Samples.file_type May is NULL [sql:u ' INSERT into samples (file_size, File_type, MD5, CRC32, SHA1, SHA SHA512, Ssdeep) VALUES (?,?,?,?,?,?,?,?) [Parameters: (+, none, ' hello ', ' crc32 ', ' sha1 ', ' sha256 ', ' sha512 ', none)]Tip for File_type cannot be empty, but when I insert the File_type
This article mainly introduces the ing class of the PythonORM framework SQLAlchemy learning notes using instances and Session sessions. For more information, see
1. create a ing Instance)
We have introduced how to map database entity tables to Python classes. now we can create an Instance for this class. we are still using the User class in the previous article as an example, let's create a User object:
The code is as follows:
>>> Ed_user = User ('e
Flask-sqlalchemy Installation and table operation please refer to here.
Copy Code code as follows:
# Role Table
Class role (db. Model):
Id=db. Column (db. Integer,primary_key=true)
Name=db. Column (db. String (80))
# Roletype Table
Class Role_type (db. Model):
Query_class=common_list_name_query
Id=db. Column (db. Integer,primary_key=true)
Name=db. Column (db. String (120))
OneYou just need to change the
Tags: types import lis List Blog har choices span sessionSQLAlchemy the choice method is not available as Django when working with database tables, we start by importing sqlalchemy-utils to provide this functionality for usPIP3 Install Sqlalchemy-utils fromSqlalchemy_utilsImportChoicetype Base=declarative_base ()classXuan (Base):__tablename__='Xuan'types_choices= ( (1,'Europe'),
Tags: Python library class table name for fine define class user matchORM Technology: Object-relational Mapping is responsible for mapping the table structure of a relational database to an object. 1. Installing the SQLAlchemy module Pip Install SQLAlchemy 2. Initializing the connection 1 #!/usr/bin/env python
2 #-*-coding:utf-8-*-
3
4 fromSQLAlchemyImportColumn, Create_engine5 fromSqlalchemy.typesImport
Label:Know: What is the experience of manipulating a database using SQLAlchemy orm? Answer: Cool! This article is based on: Win10 + python3.4 + sqlAlchemy 1.0.13 The following steps are shown:1. Declaring a base class from Import declarative_base
= Declarative_base () 2. Defining tables fromSQLAlchemyImportColumn, Integer, ForeignKey fromSqlalchemy.ormImportRelationshipclassParent (Base):__tablename__='
Come to this company has been a week, spent the beginning of the boring days ready to formally do something, these days contacted the file database InterBase, try to connect their open source version Firebird on Ubuntu, because the company uses SQLAlchemy, So I'm going to use Python to illustrate the example.#安装firebird数据库sudo apt-get install Firebird-super2. Change the password for the database administrator sysdba in Firebird:sudo dpkg-reconfigure f
modification or reading, we trigger a series of actions inside the ORM.
Wait, you haven't said why ID this attribute will be the none value. Well, in fact, we do not insert data into the database, the general primary key this property will automatically produce a distinct value to ensure uniqueness when inserting the database. Since we do not persist the object (Persist) (the so-called persistence is to store the object data in the database according to the mapping relationship), the ID value
One SQL script defined by sqlalchemy from the model class to the database table automatically generates logs
CREATE TABLE session (session_id VARCHAR(128) NOT NULL, atime TIMESTAMP NULL, data TEXT, PRIMARY KEY (session_id))
A python model class is defined as follows:
class Group(Base): __tablename__ = 'group' id = Column(Integer, primary_key=True) name = Column(String(64), nullable=False) users = relationship("User", secondary=group_u
, which means that when we use these attributes, including modification or reading, it triggers a series of actions within the ORM.
Wait, you haven't said understand why ID this attribute is a none value. Oh, in fact, we do not insert data into the database, the general primary key this property will automatically generate a duplicate value when inserting the database to ensure uniqueness. Since we do not persist objects (Persist) (the so-called persistence is to store the object data in the d
Tags: max TE mysq Connection Database code nbsp SQL Thread Reset #Connect to a database, create a table
defCreate_all (): Engine=Create_engine ('Mysql+pymysql://root:[email Protected]:3306/sqlalchemy_test?charset=utf8', Max_overflow=0,#most connections created outside the connection pool sizePool_size=5,#Connection Pool SizePool_timeout=30,#There are no threads in the pool waiting for the most time, otherwise the errorPool_recycle=-1#how long after a connection to a thread in a thread pool is re
Tags: variable logs query print SSI span over instance--One: Object Relationship Tutorial Query a method to Query use Session的query() when creating an object . This function accepts a parameter of the number of variables, which can be a combination of any class and class-instrumented descriptor. QueryIt loads the User instance for inch session.query (User). Order_by (user.id):
Print (instance.name,instance.fullname)
----------------------------------------------------------------
ed
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