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How to Retrieve Records from Top of Table: SQL Programming

Sql Programming provides a specific keyword that enables programmer to retrieve records from the top of the table. Programmer can use the TOP keyword to retrieve only the first set of rows from the top of a table. This set of records can be either a number of records or a percent of rows that will be returned from a query result.

For example, you want to view the product details from the product table, where the product price is more than $50. There might be various records in the table, but you want to see only the top 10 records that satisfy the condition. In such a case, you can use the TOP keyword.

The syntax of using the TOP keyword in the SELECT statement is:

SELECT [TOP n{PERENT}] column_name [, column_name…]
FROM table_name
WHERE search_conditions
[ORDER BY [column_name [, column_name…]

Where

  • n is the number of rows that you want to retrieve.
  • If the PERCENT keyword is used, then ‘n’ percent of the rows are returned.
  • If the SELECT statement including TOP has an ORDER BY clause, then the rows to be returned are selected after the ORDER BY clause has been applied.

The following SQL query retrieves the top three records from the Employee table where the HireDate should be greater than or equal to 1/1/2002 and less than or equal to 12/31/2005. Further, the record should be displayed in the ascending order based on the SickLeaveHours column:

SELECT TOP 3 *
FROM HumanResources.Employee
WHERE HIreDate >= '1/1/2002' AND HireDate <= '12/31/2005'
ORDER BY SickLeaveHours ASC

Output: The result from the above sql query will be only top three records after satisfying the given condition.

 How to Retrieve Records from Top of Table: SQL Programming


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