What is singleton database class?

A singleton class is a class that has only one instance object. While not necessary for having a singleton, usually the class makes sure that it is only instantiated once. E.g. in Java you could use a private constructor and a static getInstacnce() method that returns the same instance again and again.

Can I use singleton for database connection?

If we look at Database Connection class, singleton pattern can be very suitable for this. Because we can manage Db Connection via one instance so we can control load balance, unnecessary connection, shared db connection management, etc. Many Db driver can not manage same instance under multiple thread.

What is singleton class and why it is used?

It is used where only a single instance of a class is required to control the action throughout the execution. A singleton class shouldn’t have multiple instances in any case and at any cost. Singleton classes are used for logging, driver objects, caching and thread pool, database connections.

Should SQL connection be singleton?

Using a Singleton for a SqlConnection object is a really, really bad idea. There is no reason to do this whatsoever. If you are attempting to avoid a performance hit of “new SqlConnection()” or “connection.

What is singleton in SQL?

A singleton query is one that returns no more than one row, which is common in OLTP workloads. There is also a scalar query, which returns a single row and column.

Is connection pool singleton?

A connection pool might be one of the only valid use cases for a singleton pattern (which you usually want to avoid). Connections themselves should not be singletons, but CAN be managed by a singleton.

Why singleton is bad for database connection?

many DB drivers are not thread safe. Using a singleton means that if you have many threads, they will all share the same connection. The singleton pattern does not give you thread saftey. It merely allows many threads to easily share a “global” instance.

When we should use Singleton pattern?

Use the Singleton pattern when a class in your program should have just a single instance available to all clients; for example, a single database object shared by different parts of the program. The Singleton pattern disables all other means of creating objects of a class except for the special creation method.

What is the benefit of Singleton pattern?

Instance control: Singleton prevents other objects from instantiating their own copies of the Singleton object, ensuring that all objects access the single instance. Flexibility: Since the class controls the instantiation process, the class has the flexibility to change the instantiation process.

Is SqlConnection thread safe?

Note that SqlConnection instance is not guaranteed to be thread safe. You should avoid using the same SqlConnection in several threads at the same time. It is recommended to open a new connection per thread and to close it when the work is done.

Why do we use Singleton pattern in C#?

We need to use the Singleton Design Pattern in C# when we need to ensures that only one instance of a particular class is going to be created and then provide simple global access to that instance for the entire application.

What is a singleton class in Java?

A Singleton class in Java allows only one instance to be created and provides global access to all other classes through this single object or instance. Similar to the static fields, The instance fields(if any) of a class will occur only for a single time.