See the following Examples section in this article. The following examples use a constant value to specify the number of employees that are returned in the query result set. The following example uses a variable to specify the number of employees that are returned in the query result set. There are employees in the HumanResources.
Employee table. Because five percent of is a fractional value, the value is rounded up to the next whole number. The following example gets the top 10 percent of all employees with the highest salary and returns them in descending order according to their salary. Specifying WITH TIES ensures that employees with salaries equal to the lowest salary returned the last row are also included in the result set, even if it exceeds 10 percent of employees.
The following example deletes 20 rows from the PurchaseOrderDetail table that have due dates earlier than July 1, The following query deletes the 10 rows of the PurchaseOrderDetail table that have the earliest due dates.
To ensure that only 10 rows are deleted, the column specified in the subselect statement PurchaseOrderID is the primary key of the table. Using a nonkey column in the subselect statement may result in the deletion of more than 10 rows if the specified column contains duplicate values.
The following example creates the table EmployeeSales and inserts the name and year-to-date sales data for the top five employees from the table HumanResources. The following example show how to do this. The following example uses the TOP clause to update rows in a table.
The following example assigns 10 customers from one salesperson to another. The following example updates the vacation hours of the 10 employees with the earliest hire dates. Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support.
Feedback will be sent to Microsoft: By pressing the submit button, your feedback will be used to improve Microsoft products and services. Privacy policy. The samples in this article use the AdventureWorks database available for download at AdventureWorks sample databases.
A subquery can be used anywhere an expression is allowed. A subquery is also called an inner query or inner select, while the statement containing a subquery is also called an outer query or outer select. Many Transact-SQL statements that include subqueries can be alternatively formulated as joins. Other questions can be posed only with subqueries.
In Transact-SQL, there is usually no performance difference between a statement that includes a subquery and a semantically equivalent version that does not. However, in some cases where existence must be checked, a join yields better performance. Otherwise, the nested query must be processed for each result of the outer query to ensure elimination of duplicates. In such cases, a join approach would yield better results. Up to 32 levels of nesting is possible, although the limit varies based on available memory and the complexity of other expressions in the query.
Individual queries may not support nesting up to 32 levels. A subquery can appear anywhere an expression can be used, if it returns a single value. If a table appears only in a subquery and not in the outer query, then columns from that table cannot be included in the output the select list of the outer query.
In some Transact-SQL statements, the subquery can be evaluated as if it were an independent query. Conceptually, the subquery results are substituted into the outer query although this is not necessarily how SQL Server actually processes Transact-SQL statements with subqueries.
Customer table. The general rule is that column names in a statement are implicitly qualified by the table referenced in the FROM clause at the same level. If a column does not exist in the table referenced in the FROM clause of a subquery, it is implicitly qualified by the table referenced in the FROM clause of the outer query.
It is never wrong to state the table name explicitly, and it is always possible to override implicit assumptions about table names with explicit qualifications. If a column is referenced in a subquery that does not exist in the table referenced by the subquery's FROM clause, but exists in a table referenced by the outer query's FROM clause, the query executes without error. SQL Server implicitly qualifies the column in the subquery with the table name in the outer query.
A subquery can itself include one or more subqueries. Any number of subqueries can be nested in a statement. The innermost query returns the sales person IDs.
The query at the next higher level is evaluated with these sales person IDs and returns the contact ID numbers of the employees. Finally, the outer query uses the contact IDs to find the names of the employees.
Many queries can be evaluated by executing the subquery once and substituting the resulting value or values into the WHERE clause of the outer query. In queries that include a correlated subquery also known as a repeating subquery , the subquery depends on the outer query for its values. This means that the subquery is executed repeatedly, once for each row that might be selected by the outer query.
This query retrieves one instance of each employee's first and last name for which the bonus in the SalesPerson table is and for which the employee identification numbers match in the Employee and SalesPerson tables.
The previous subquery in this statement cannot be evaluated independently of the outer query. It gives you rows 5 through 14, but you want rows 11 through In general, it fails for the last "page" of a result, unless the total rows are a multiple of that "page" size.
Such a simple thing needs to be made so difficult by MS yet again! This is not a good answer for any of the current SQL Server versions. Clunky, but it'll work. Do you have another suggestion to bypass this? Not pleasant, but it works. This solution works only if the result set includes a column that is unique.
I'm in a similar quandary right now However, in my case I'm hosed It's even more criminal when so called 'expert' dba's decide that an unique key in unnecessary in a table ANY table Don't even bring up the subject of foreign keys and constraints! I'm going to try temp tables, as its not working for me. HoldOffHunger Using 'with' only needs half the time to finish querying - see the answer of Leon Tayson. I have no idea what Microsoft did to make it that slow.
Why is this not the accepted answer? We are in for crying out loud! Skipper right. Let's just upvote this one to reflect the update. That query will scan and lock the entire table — Panagiotis Kanavos. Jeremy Jeremy 1 1 gold badge 4 4 silver badges 14 14 bronze badges. Agree to this. For me I need to use this condition for my custom native query ,hence vanilla findBy clauses of JPA didn't helped much.
This options worked as expected. Please see this page as best references I have seen: sqlservertutorial. Community Bot 1 1 1 silver badge. Bill Karwin Bill Karwin k 82 82 gold badges silver badges bronze badges.
And it's pretty clunky of course That covers an huge majority of the SQL market.
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