In SQL Server, the @@SERVERNAME configuration function returns the name of the local server that is running SQL Server.
No argument is required. You can simply use it in a SELECT statement to return the server name.
Tag: functions
Create a Computed Column that Uses Data from Another Table in SQL Server
A widely known limitation of computed columns in SQL Server is that they can’t access data from other tables. That is, your expression can use columns in the same table, but not from other tables.
But this is only half-true. While you can’t reference another table’s column directly within your expression, you can invoke a user-defined function. And therefore, you could create a user-defined function that performs the calculation you need, then simply call that function as your computed column’s expression.
Here’s an example to demonstrate.
Continue readingHow @@MAX_CONNECTIONS Works in SQL Server
In SQL Server, the @@MAX_CONNECTIONS configuration function returns the maximum number of simultaneous user connections allowed on an instance of SQL Server. The number returned is not necessarily the number currently configured.
No argument is required. You can simply use it in a SELECT statement to return the maximum number of simultaneous user connections allowed on the current server.
What is @@MAX_PRECISION in SQL Server?
In SQL Server, the @@MAX_PRECISION configuration function returns the precision level used by decimal and numeric data types as currently set in the server.
No argument is required. You can simply use it in a SELECT statement to return the precision level of the current server.
Use CRYPT_GEN_RANDOM() to Create a Cryptographic, Random Number in SQL Server
In SQL Server, you can use the CRYPT_GEN_RANDOM() function to return a cryptographic, randomly-generated number. The number is generated by the Cryptographic Application Programming Interface (CAPI).
CAPI is a Microsoft Windows platform specific application programming interface included with Microsoft Windows operating systems that provides services to enable developers to secure Windows-based applications using cryptography.
The CRYPT_GEN_RANDOM() function accepts two arguments: the length (required), and a seed (optional).
The return value is varbinary(8000).
2 Ways to Return All User-Defined Functions in a SQL Server Database
This article presents two ways to return a list of user-defined functions in a SQL Server database.
Return the Base Data Type from a SQL_Variant Value in SQL Server
In SQL Server, you can use the SQL_VARIANT_PROPERTY() function to return base data type information from a sql_variant value.
The function accepts two arguments: the sql_variant value, and the property for which information is to be provided.
LEFT() vs SUBSTRING() in SQL Server: What’s the Difference?
In SQL Server environments, two of the many string functions at our disposal are LEFT() and SUBSTRING().
These functions do a similar thing, but there are differences. This article looks at some of the main differences between these functions.
LEFT() vs SET TEXTSIZE in SQL Server: What’s the Difference?
You may be familiar with the SET TEXTSIZE statement in SQL Server, that enables you to limit the amount of data returned in a SELECT query.
Perhaps you’re finding that its results are exactly the same as LEFT() when running a specific query. Which begs the question: Is there a difference between these two options?
What is @@TEXTSIZE in SQL Server?
In SQL Server, the @@TEXTSIZE configuration function returns the current value of the TEXTSIZE option.
No argument is required. You can simply use it in a SELECT statement to return the current TEXTSIZE value.
The TEXTSIZE value specifies the size of varchar(max), nvarchar(max), varbinary(max), text, ntext, and image data returned by a SELECT statement. This value can be set using SET TEXTSIZE.