SQL Server offers many built in metadata functions and one of these functions, @@OPTIONS which allows you to get the current values that are set for the current session. When each connection is made the default values are established for each connection and remain set unless they are overridden by some other process.
What does @@ mean in SQL Server?
In SQL Server, symbol @@ is prefixed to global variables. The server maintains all the global variables. … Global variable names begin with a @@ prefix. You do not need to declare them, since the server constantly maintains them. They are system-defined functions and you cannot declare them.
What is select @@ SPID?
Select Distinct » A SPID in SQL Server is a Server Process ID. These process ID’s are essentially sessions in SQL Server. Everytime an application connects to SQL Server, a new connection (or SPID) is created. This connection has a defined scope and memory space and cannot interact with other SPIDs.
What are SQL Server options?
OPTION Clause in SQL Server. The OPTION clause is used to query the table with different query hint. This clause can be specified in different statements like SELECT, UPDATE, MERGE and DELETE. Only one OPTION clause can be specified in a statement.
What is option label in SQL?
Using a query label in Azure SQL DW (Data Warehouse) can be a really handy technique to track queries via DMVs. You might want to do this to see what problematic queries are doing under the covers. … OPTION (LABEL = ‘QUERY: MySalesCodeSum’ ); We then use this LABEL within the DMV based query.
What is @@ Identity in SQL?
The @@IDENTITY is a system function that returns the last IDENTITY value generated for any table with an identity column under the current session, regardless of the scope of the T-SQL statement that generated the value.
What is the difference between and @@ in SQL Server?
1 Answer. There is no difference. The rules for variables state that they start with an ‘@’ character and follow the rules for identifiers. Since ‘@’ is a valid identifier character, you can have as many as you like at the start of your variable name.
Is Session_id same as SPID?
Every process in SQL Server is running under a server process. They are referred to as session IDs. Each of these session processes has a unique ID known as SPID.
What is running on SPID SQL Server?
We often need to find the last running query or based on SPID need to know which query was executed. SPID is returns sessions ID of the current user process. The acronym SPID comes from the name of its earlier version, Server Process ID. … In session with SPID 61, we will run any query.
What is Sp_lock?
The sp_lock system stored procedure is a great tool for checking the amount of locking that occurs on your database system. It returns the number and types of locks that are being held by current active SQL Server sessions.
What is Option Force order in SQL Server?
The FORCE ORDER is a query hint it executes the order of the tables exactly specified in a statement. When we use this query hint in a statement it will tell SQL server not to change the order of the joins in the query. … OPTION(FORCE ORDER);
What is option hash join?
Hash join is used when projections of the joined tables are not already sorted on the join columns. In this case, the optimizer builds an in-memory hash table on the inner table’s join column. The optimizer then scans the outer table for matches to the hash table, and joins data from the two tables accordingly.
What is option hash join in SQL Server?
Hash joins are built using hash tables, which are assembled in-memory by SQL Server. … ON a.id = b.id ) are hashed using a proprietary hash function, then put into a hash table. This is called the build phase.
What are labels options?
The HTML option label Attribute is used to specify the text value which represents the shorted label for option. … Attribute Values: It contains single value text which specify the shorter version for an option.
What is option Maxdop 1 in SQL Server?
Sets the maximum number of processors the query processor can use to execute a single index statement. Fewer processors may be used depending on the current system workload.
What are labels used for?
Labels may be used for any combination of identification, information, warning, instructions for use, environmental advice or advertising. They may be stickers, permanent or temporary labels or printed packaging.