NET code samples that demonstrate how to use the SqlDataAdapter object to update a SQL Server database with data modifications that are run on a DataSet object that is populated with data from a table in the database. Requirements The following list outlines the recommended hardware, software, network infrastructure, skills and knowledge, and service packs that are required: NET DataSet object with data that is retrieved from a SQL Server database and then updates the database to reflect the changes such as inserts, updates, and deletes that are made to the data by using the DataSet object.
In the CASE example, one pass through the data is sufficient to return the correct results. Another very useful capability of CASE expressions is to transform a result set from multiple rows into a summary row.
Consider the situation where sales data is stored in a table by month.
One row is stored per month with a table structure that looks like the following: The mnth column stores an integer value ranging from 1 for January to 12 for December. You can use the following single SQL statement to product one row per product with 12 totals, one for each month: The CASE expression causes the sales amount to by added to the appropriate bucket by checking the mnth column.
Using CASE expressions in this manner simplifies aggregation and reporting. It provides a quick way of transforming normalized data structures into the more common denormalized formats that most business users are accustomed to viewing on reports. This same basic idea can be used to create many types of summary rows.
For example, to produce a summary row by quarter instead of by month, simply modify the CASE expressions as shown below: Consider, once again, the sample pubs database.
The following query checks the royalty percentage by title and places the percentage into a category based on its value:The above SQL statement works in the same way that the UPDATE statement worked when we used a sub-SELECT except with this statement records are deleted and not UPDATED.
With SQL, the sub-SELECT statement is executed first. To update data in a table, you need to: First, specify the table name that you want to change data in the UPDATE clause.
Second, assign a new value for the column that you want to update. In case you want to update data in multiple columns, each column = value pair is separated by a comma (,). Using SQL statements in Excel enables you to connect to an external data source, parse field or table contents and import data – all without having to input the data manually.
I have a maintenance sql script, that has basically 6 update statements. All the 6 statements are update the same table.
The table has rows. The SQL UPDATE Query is used to modify the existing records in a table. You can use the WHERE clause with the UPDATE query to update the selected rows, otherwise all the rows would be affected.
The basic syntax of the UPDATE query with a WHERE clause is as follows −. SQL uses the "UPDATE" statement to alter/change data in your tables.
Just like the SELECT statement, you need to specify columns and a table, but the UPDATE statement also requires the new data you want to store.