What is a linked server?
Linked Servers are a method by which a SQL Server can talk to another ODBC compliant database, such as another SQL Server instance or an Oracle database, with a direct T-SQL query. There are several important settings to know when setting up a Linked Server.
How does identity work in SQL Server?
A SQL Server IDENTITY column is a special type of column that is used to automatically generate key values based on a provided seed (starting point) and increment. SQL Server provides us with a number of functions that work with the IDENTITY column. In this tip, we will go through these functions with examples.
What is identity and Scope_identity?
SCOPE_IDENTITY and @@IDENTITY will return the last identity values generated in any table in the current session. However, SCOPE_IDENTITY returns values inserted only within the current scope; @@IDENTITY is not limited to a specific scope. A scope is a module; a Stored Procedure, trigger, function, or batch.
How do I select a linked server?
Right-click on the Linked Server node and choose New Linked Server. In the General tab of the New Linked Server window, choose a name for your linked server, then choose the type of the server you need to connect to using that linked server.
Why would you use a linked server?
Linked servers enable you to implement distributed databases that can fetch and update data in other databases. They are a good solution in the scenarios where you need to implement database sharding without need to create a custom application code or directly load from remote data sources.
How does a linked server work?
A linked server allows for access to distributed, heterogeneous queries against OLE DB data sources. After a linked server is created, distributed queries can be run against this server, and queries can join tables from more than one data source.
What is Identity in SQL with example?
In SQL Server, we create an identity column to auto-generate incremental values. It generates values based on predefined seed (Initial value) and step (increment) value. For example, suppose we have an Employee table and we want to generate EmployeeID automatically.
How does Scope_identity work in SQL Server?
The SCOPE_IDENTITY() function returns the null value if the function is invoked before any INSERT statements into an identity column occur in the scope. Failed statements and transactions can change the current identity for a table and create gaps in the identity column values.
What is Scope_identity in SQL Server 2008 example?
SCOPE_IDENTITY() – Return the last identity values that are generated in any table in the current session. SCOPE_IDENTITY returns values inserted only within the current scope. This example defines how they generate a different identity value.