Database Class

Definition

Namespace:

System.Data.Entity

Assembly:

EntityFramework.dll

An instance of this class is obtained from an DbContext object and can be used to manage the actual database backing a DbContext or connection. This includes creating, deleting, and checking for the existence of a database. Note that deletion and checking for existence of a database can be performed using just a connection (i.e. without a full context) by using the static methods of this class.

[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1001:TypesThatOwnDisposableFieldsShouldBeDisposable", Justification="The DbContextTransaction and EntityTransaction should never be disposed by this class")]
public class Database

type Database = class

Public Class Database

Inheritance

Object

Database

Attributes

SuppressMessageAttribute

Properties

CommandTimeout	Gets or sets the timeout value, in seconds, for all context operations. The default value is null, where null indicates that the default value of the underlying provider will be used.
Connection	Returns the connection being used by this context. This may cause the connection to be created if it does not already exist.
CurrentTransaction	Gets the transaction the underlying store connection is enlisted in. May be null.
DefaultConnectionFactory	Obsolete. The connection factory to use when creating a DbConnection from just a database name or a connection string.
Log	Set this property to log the SQL generated by the DbContext to the given delegate. For example, to log to the console, set this property to Write(String).

Methods

BeginTransaction()	Begins a transaction on the underlying store connection
BeginTransaction(IsolationLevel)	Begins a transaction on the underlying store connection using the specified isolation level
CompatibleWithModel(Boolean)	Checks whether or not the database is compatible with the the current Code First model.
Create()	Creates a new database on the database server for the model defined in the backing context. Note that calling this method before the database initialization strategy has run will disable executing that strategy.
CreateIfNotExists()	Creates a new database on the database server for the model defined in the backing context, but only if a database with the same name does not already exist on the server.
Delete()	Deletes the database on the database server if it exists, otherwise does nothing. Calling this method from outside of an initializer will mark the database as having not been initialized. This means that if an attempt is made to use the database again after it has been deleted, then any initializer set will run again and, usually, will try to create the database again automatically.
Delete(DbConnection)	Deletes the database on the database server if it exists, otherwise does nothing.
Delete(String)	Deletes the database on the database server if it exists, otherwise does nothing. The connection to the database is created using the given database name or connection string in the same way as is described in the documentation for the DbContext class.
Equals(Object)	Determines whether the specified object is equal to the current object.
ExecuteSqlCommand(String, Object[])	Executes the given DDL/DML command against the database. As with any API that accepts SQL it is important to parameterize any user input to protect against a SQL injection attack. You can include parameter place holders in the SQL query string and then supply parameter values as additional arguments. Any parameter values you supply will automatically be converted to a DbParameter. context.Database.ExecuteSqlCommand("UPDATE dbo.Posts SET Rating = 5 WHERE Author = @p0", userSuppliedAuthor); Alternatively, you can also construct a DbParameter and supply it to SqlQuery. This allows you to use named parameters in the SQL query string. context.Database.ExecuteSqlCommand("UPDATE dbo.Posts SET Rating = 5 WHERE Author = @author", new SqlParameter("@author", userSuppliedAuthor));
ExecuteSqlCommand(TransactionalBehavior, String, Object[])	Executes the given DDL/DML command against the database. As with any API that accepts SQL it is important to parameterize any user input to protect against a SQL injection attack. You can include parameter place holders in the SQL query string and then supply parameter values as additional arguments. Any parameter values you supply will automatically be converted to a DbParameter. context.Database.ExecuteSqlCommand("UPDATE dbo.Posts SET Rating = 5 WHERE Author = @p0", userSuppliedAuthor); Alternatively, you can also construct a DbParameter and supply it to SqlQuery. This allows you to use named parameters in the SQL query string. context.Database.ExecuteSqlCommand("UPDATE dbo.Posts SET Rating = 5 WHERE Author = @author", new SqlParameter("@author", userSuppliedAuthor));
ExecuteSqlCommandAsync(String, CancellationToken, Object[])	Asynchronously executes the given DDL/DML command against the database. As with any API that accepts SQL it is important to parameterize any user input to protect against a SQL injection attack. You can include parameter place holders in the SQL query string and then supply parameter values as additional arguments. Any parameter values you supply will automatically be converted to a DbParameter. context.Database.ExecuteSqlCommandAsync("UPDATE dbo.Posts SET Rating = 5 WHERE Author = @p0", userSuppliedAuthor); Alternatively, you can also construct a DbParameter and supply it to SqlQuery. This allows you to use named parameters in the SQL query string. context.Database.ExecuteSqlCommandAsync("UPDATE dbo.Posts SET Rating = 5 WHERE Author = @author", new SqlParameter("@author", userSuppliedAuthor));
ExecuteSqlCommandAsync(String, Object[])	Asynchronously executes the given DDL/DML command against the database. As with any API that accepts SQL it is important to parameterize any user input to protect against a SQL injection attack. You can include parameter place holders in the SQL query string and then supply parameter values as additional arguments. Any parameter values you supply will automatically be converted to a DbParameter. context.Database.ExecuteSqlCommandAsync("UPDATE dbo.Posts SET Rating = 5 WHERE Author = @p0", userSuppliedAuthor); Alternatively, you can also construct a DbParameter and supply it to SqlQuery. This allows you to use named parameters in the SQL query string. context.Database.ExecuteSqlCommandAsync("UPDATE dbo.Posts SET Rating = 5 WHERE Author = @author", new SqlParameter("@author", userSuppliedAuthor));
ExecuteSqlCommandAsync(TransactionalBehavior, String, CancellationToken, Object[])	Asynchronously executes the given DDL/DML command against the database. As with any API that accepts SQL it is important to parameterize any user input to protect against a SQL injection attack. You can include parameter place holders in the SQL query string and then supply parameter values as additional arguments. Any parameter values you supply will automatically be converted to a DbParameter. context.Database.ExecuteSqlCommandAsync("UPDATE dbo.Posts SET Rating = 5 WHERE Author = @p0", userSuppliedAuthor); Alternatively, you can also construct a DbParameter and supply it to SqlQuery. This allows you to use named parameters in the SQL query string. context.Database.ExecuteSqlCommandAsync("UPDATE dbo.Posts SET Rating = 5 WHERE Author = @author", new SqlParameter("@author", userSuppliedAuthor));
ExecuteSqlCommandAsync(TransactionalBehavior, String, Object[])	Asynchronously executes the given DDL/DML command against the database. As with any API that accepts SQL it is important to parameterize any user input to protect against a SQL injection attack. You can include parameter place holders in the SQL query string and then supply parameter values as additional arguments. Any parameter values you supply will automatically be converted to a DbParameter. context.Database.ExecuteSqlCommandAsync("UPDATE dbo.Posts SET Rating = 5 WHERE Author = @p0", userSuppliedAuthor); Alternatively, you can also construct a DbParameter and supply it to SqlQuery. This allows you to use named parameters in the SQL query string. context.Database.ExecuteSqlCommandAsync("UPDATE dbo.Posts SET Rating = 5 WHERE Author = @author", new SqlParameter("@author", userSuppliedAuthor));
Exists()	Checks whether or not the database exists on the server.
Exists(DbConnection)	Checks whether or not the database exists on the server.
Exists(String)	Checks whether or not the database exists on the server. The connection to the database is created using the given database name or connection string in the same way as is described in the documentation for the DbContext class.
GetHashCode()	Serves as the default hash function.
GetType()	Gets the Type of the current instance.
Initialize(Boolean)	Runs the the registered IDatabaseInitializer<TContext> on this context. If "force" is set to true, then the initializer is run regardless of whether or not it has been run before. This can be useful if a database is deleted while an app is running and needs to be reinitialized. If "force" is set to false, then the initializer is only run if it has not already been run for this context, model, and connection in this app domain. This method is typically used when it is necessary to ensure that the database has been created and seeded before starting some operation where doing so lazily will cause issues, such as when the operation is part of a transaction.
SetInitializer<TContext>(IDatabaseInitializer<TContext>)	Sets the database initializer to use for the given context type. The database initializer is called when a the given DbContext type is used to access a database for the first time. The default strategy for Code First contexts is an instance of CreateDatabaseIfNotExists<TContext>.
SqlQuery(Type, String, Object[])	Creates a raw SQL query that will return elements of the given type. The type can be any type that has properties that match the names of the columns returned from the query, or can be a simple primitive type. The type does not have to be an entity type. The results of this query are never tracked by the context even if the type of object returned is an entity type. Use the SqlQuery(String, Object[]) method to return entities that are tracked by the context.
SqlQuery<TElement>(String, Object[])	Creates a raw SQL query that will return elements of the given generic type. The type can be any type that has properties that match the names of the columns returned from the query, or can be a simple primitive type. The type does not have to be an entity type. The results of this query are never tracked by the context even if the type of object returned is an entity type. Use the SqlQuery(String, Object[]) method to return entities that are tracked by the context.
ToString()	Returns a string that represents the current object.
UseTransaction(DbTransaction)	Enables the user to pass in a database transaction created outside of the Database object if you want the Entity Framework to execute commands within that external transaction. Alternatively, pass in null to clear the framework's knowledge of that transaction.