![]() So that each Session generated will use this Engine We’ve configured the factory to specify a particular Engine forĪ typical setup will associate the sessionmaker with an Engine, This factory, whenĬalled, will create a new Session object using the configurationalĪrguments we’ve given the factory. commit ()Ībove, the sessionmaker call creates a factory for us, The usage of sessionmaker is illustrated below:įrom sqlalchemy import create_engine from sqlalchemy.orm import sessionmaker # an Engine, which the Session will use for connection # resources some_engine = create_engine ( ) # create a configured "Session" class Session = sessionmaker ( bind = some_engine ) # create a Session session = Session () # work with sess myobject = MyObject ( 'foo', 'bar' ) session. Need to repeat the configurational arguments. However, to standardize how sessions are configuredĪnd acquired, the sessionmaker class is normallyĬonfiguration which can then be used throughout an application without the Session is a regular Python class which canīe directly instantiated. Want to work with them again, so that they can resume their normal task of Usually, you’d re-associate detached objects with another Session when you ![]() Them, though this practice has its caveats. Possible to “detach” objects from a Session, and to continue using Objects to re-access the database in order to keep synchronized. Held by the Session - there are a variety of events that will cause Which are associated with it are proxy objects to the transaction being When using a Session, it’s important to note that the objects It flushes all pending changes to the database. The database is queried again or before the current transaction is committed, Remains in effect until the Session is instructed to commit or rollĪll changes to objects maintained by a Session are tracked - before This connection represents an ongoing transaction, which Session itself or with the mapped Table objects being Resource from an Engine that is associated either with the Once queriesĪre issued or other objects are persisted with it, it requests a connection The Session begins in an essentially stateless form. That maintains unique copies of each object, where “unique” means “only one Session, inside a structure called the Identity Map - a data structure Queries to the database using the Session object’s current databaseĬonnection, populating result rows into objects that are then stored in the Provides the entrypoint to acquire a Query object, which sends Objects which you’ve loaded or associated with it during its lifespan. In the most general sense, the Session establishes allĬonversations with the database and represents a “holding zone” for all the Session Basics ¶ What does the Session do ? ¶ Tracking Object and Session Changes with Events.Deleting Objects Referenced from Collections and Scalar Relationships.How can I get the Session for a certain object?.When do I construct a Session, when do I commit it, and when do I close it?.Creating Ad-Hoc Session Objects with Alternate Arguments.Adding Additional Configuration to an Existing sessionmaker().For information about how to read values from session state, see How to: Read Values from Session State. ![]() For information about how to enable session state, see Configuring Session State in ASP.NET Session State Overview.įor information about how to save values in session state, see How to: Save Values in Session State. In order to use session state you have to enable it. The Session property provides programmatic access to the properties and methods of the HttpSessionState class. ![]() ' Outside of Web Forms page class, use HttpContext.Current.ĭim context As HttpContext = HttpContext.CurrentįirstName = DirectCast(context.Session("FirstName"), String) LastName = DirectCast(Session("LastName"), String)Ĭity = DirectCast(Session("City"), String) ' Read from session state in a Web Forms page class.įirstName = DirectCast(Session("FirstName"), String) ' Save to session state in a Web Forms page class. ![]() HttpContext context = HttpContext.Current Ĭontext.Session = firstName įirstName = (string)(context.Session) Outside of Web Forms page class, use HttpContext.Current. Read from session state in a Web Forms page class.įirstName = (string)(Session) Save to session state in a Web Forms page class. The following examples show how to save values in session state and how to read values from session state.Īn ASP.NET application that has session state enabled.Ī Web Forms page class that has access to the Page.Session property, or any class that has access to the HttpContext.Current property. The HttpSessionState object for the current HTTP request. Property System::Web::SessionState::HttpSessionState ^ Session member this.Session : Public ReadOnly Property Session As HttpSessionState Property Value HttpSessionState Gets the HttpSessionState object for the current HTTP request. ![]()
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