Delete sql statement null

You can drop the clustered index after the rows are deleted. This method is more time consuming than the previous methods and uses more temporary resources.

Examples in this section demonstrate the basic functionality of the DELETE statement using the minimum required syntax. The following example deletes all rows from the ProductCostHistory table in the AdventureWorks database in which the value in the StandardCost column is more than The value in the StandardCost column must be between The delete operation affects only the single row currently fetched from the cursor.

The following examples show two ways to delete rows in one table based on data in another table. In both examples, rows from the SalesPersonQuotaHistory table in the AdventureWorks database are deleted based on the year-to-date sales stored in the SalesPerson table. The following example deletes 20 random rows from the PurchaseOrderDetail table in the AdventureWorks database that have due dates that are 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.

Examples in this section demonstrate how to delete rows from a remote table by using a linked server or a rowset function to reference the remote table. A remote table exists on a different server or instance of SQL Server. The following example deletes rows from a remote table. The linked server name, MyLinkServer , is then specified as part of the four-part object name in the form server. The linked server name created in the previous example is used in this example.

You can determine the number of rows that will be deleted by running the following SELECT statement before performing the delete:. The AND condition allows you to delete a record if all of the conditions are met. The OR condition deletes a record if any one of the conditions are met.

To check for the number of rows that will be deleted, you can run the following SELECT statement before performing the delete. You may wish to delete records in one table based on values in another table. In this foreign key example, we've created our parent table as the products table.

Next, we've created a second table called inventory that will be the child table in this foreign key example. Now one important thing about setting up this foreign key!!! While using this site, you agree to have read and accepted our Terms of Service and Privacy Policy. Please re-enable javascript in your browser settings.