Can you index a table variable

But in some instances, the temp table, or table variable may contain several hundred to values. Thus the desire to understand your opinion on the issue of table variables with large number of records.

You mentioned a join, so… How many rows are you joining? If you had a second column in your table, e. Your email address will not be published. Don't subscribe All Replies to my comments Notify me of followup comments via e-mail.

You can also subscribe without commenting. Post Comment. Want to advertise here and reach my savvy readers? Is it ever worth adding indexes to table variables? There's no true answer to which of these types are the best type to use as it depends on the task. It's very important to understand the differences among them before you decide on using one over the other. Local temp tables i. They work and act like regular tables. They can be indexed, have constraints added, and carry statistics.

Global temp tables i. Temp tables are also subject to recompiles. On the other hand, Foreign Key constraints cannot use for the table variables. The other restriction is, we have to define the constraints when we are declaring the table variable otherwise, we experience an error. For example, the following query will return an error because of this restriction. We cannot alter the table structure after the declaration of the table variable:.

Now we will execute the following query and then analyze the result:. Table variable CRUD operations do not manage by explicit transactions. However, this statement cannot be used for table variables. For example, the following query will return an error:.

If we want to join two or more table variables with each other or regular tables, we have to use an alias for the table names. The usage of this looks like this:. The new syntax works on table variables , too! This means that with SQL Server and higher, you can create non -unique nonclustered indexes on table variables.

You can even set the fillfactor option. Jessy Cirre Explainer. What is clustered index in SQL? SQL Server has two types of indexes : clustered index and non- clustered index. A clustered index stores data rows in a sorted structure based on its key values. Each table has only one clustered index because data rows can be only sorted in one order. The table that has a clustered index is called a clustered table.

Shun Casasus Pundit. What is clustered index? A clustered index is a special type of index that reorders the way records in the table are physically stored. Therefore table can have only one clustered index. The leaf nodes of a clustered index contain the data pages. Instead, the leaf nodes contain index rows. Dumitrel Zimakov Pundit. What is the difference between an index and a scale?

All scales are indices , but not all indexes are scales. An index really just means that it is a measurement that is constructed by summing up other, simpler, measurements. A scale is an index that in some sense only measures one thing.

In a larger sense, an index does measure one thing: scholastic achievement. Lekbir Wiebking Pundit. What does an index measure?