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Can we create clustered index on table variable?
Short answer: Yes. A more detailed answer is below. Traditional tables in SQL Server can either have a clustered index or are structured as heaps. Clustered indexes can either be declared as unique to disallow duplicate key values or default to non unique.
Can we use table variable in join?
f you are using a table variable in a join, you will need to alias the table in order to execute the query. You can use a table variable with dynamic SQL, but you must declare the table inside the dynamic SQL itself. The following query will fail with the error “Must declare the variable ‘@MyTable’.”
Can you pass a table variable to a stored procedure?
Passing table-valued parameters to a stored procedure is a three-step process: Create a user-defined table type that corresponds to the table that you want to populate. Pass the user-defined table to the stored procedure as a parameter.
Do you need to create Index on table variable?
The drawback is that the indexes (or constraints) need to be unique. One potential way to circumvent this however, is to create a composite unique constraint: You can also create the equivalent of a clustered index. To do so, just add the clustered reserved word. Generally, temp tables perform better in situations where an index is needed.
Is it possible to join a variable table in SQL Server?
Unfortunately, SQL Server does not support JOINning @variable tables, it is only allowed to join “true” tables, those in the database.
Do you set index on join clauses or where clauses?
Do you set an index on JOIN clauses or where clauses, or both? SELECT t1, t2 FROM t1 LEFT JOIN t2 ON (t1.id = t2.id AND t2.userid = @userid) WHERE t1.enabled = 1 AND t1.startDate <= ??? AND (t1.counter = -1 OR t2.counter IS NULL OR (t1.counter > t2.counter)
Is it possible to declare filtered indexes for table variables?
From CTP 3.1 it is now possible to declare filtered indexes for table variables. By RTM it may be the case that included columns are also allowed but the current position is that they “will likely not make it into SQL16 due to resource constraints” Can I create a index on Name?