Yesterday I come across a strange issue while I was trying to use update query with table variable. There are two different solution/workaround to this problem. When executed the update finished in 2 minutes. Table variables cannot be dropped, nor can they be re-declared. All the name of table variable in T - SQL start with at sign (@). Once you have successfully created a table variable, you can query the same table variable via following select statement. Even if you replace the table variable with SQL, it will greatly speed up query performance: select * from (Select 10377 as UserID Union all Select 73736 Union all Select 7474748 ….) At any point of time, the Table Variable will also contain 1000 to 3000 rows. Type of Variables in SQL Server Local variable: A user declares the local variable. Table Variable. SQL Declare variable table Declare variable table. Check the system catalog. It is created in the memory database but may be pushed out to tempdb. The reason is very simple, you can’t just insert the data into the table variable on the fly. SQL Server 2008. T-SQL supports many feature like variables, loops, conditions and exceptions. Table Variable Table variables are also temporary objects and they are created as with DECLARE keywords. 1 For much faster performance you can memory-optimize your table variable." "A traditional table variable represents a table in the tempdb database. Global variable: DECLARE statement is used to create a table variable. Table Variable acts like a variable and exists for a particular batch of query execution. To declare a table variable, use the DECLARE keyword, then type the @variable_name and variable type table with columns. I replaced the Cursor and used Table Variable. Every local variable scope has the restriction to the current batch or procedure within any given session. as users join Address a on a.UserID = users.UserID If you are doing more complex processing on temporary data, or need to use more than reasonably small amounts of data in them, then local temporary tables are likely to be a … Use following queries for this: The query which works fine with temporary table does not work with table variables. In order to use the in-memory technology you have to explicitly define a TYPE which is memory optimized and use that TYPE to define your table variable. It gets dropped once it comes out of batch. Instead, use a declaration statement to make available a fresh table variable. Table variables are not in-memory constructs. SQL Prompt implements this recomendation as a code analysis rule, ST011 – Consider using table variable instead of temporary table. Table variables are SQL Server local variables, but they also have some properties that resemble temp tables. Server is Windows Server 2012 64-bit with 64GB RAM. To insert values into a table variable, uses the INSERT statement based on a SELECT statement. Table variable is used to store an entire result set rather than a single value. Solution 1: Define Variable Table This is a very simple solution, first, define a table variable and right after that insert the data into it. In fact, trying to do the latter returns this error: “The variable name ‘@country’ has already been declared. Below figure explain two types of variable available in MS SQL server. Transact SQL is also known as T-SQL. Use Table variable, if you have less than 1000 rows otherwise go for Temporary tables. will return Cannot find a table or object with the name “@country”. Let us confirm this with following example: First create 2 temporary variables. 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