Start Sql updating a query result set

Sql updating a query result set

In addition, the statement can include a WHERE clause, which determines what rows to modify, or a FROM clause, which identifies tables or views that provide values for the expressions defined in the SET clause.

In the following UPDATE statement, I modify only the rows that have a Territory Name value of United Kingdom: As you can see, I specify in the SET clause that the Territory Name value should be changed to UK.

However, because the WHERE clause is also included, only the rows that currently have a value of United Kingdom are changed, which in this case, is only one row.

You’ve seen both of these types of column/value pairs in previous examples.

But the expression matched up to the Sales Last Year column is something new.

However, you’ll often want to update only specific rows. To limit the rows that are updated when you issue an UPDATE statement, add a WHERE clause after the SET clause.

The WHERE clause specifies the search conditions that define which rows in the target table should be updated.

By using an UPDATE statement, you can modify data in individual rows, sets of rows, or all rows in a table.

An UPDATE statement must always include a SET clause, which identifies the columns to be updated.

(I also add a SELECT statement to the examples to verify the data modifications.) The SELECT statement above returns the results shown in the following table: As I mentioned above, your UPDATE statement must include a SET clause.

The clause identifies which columns in the target table should be modified and what the new values should be.

However, the SET clause specifies that several columns be modified.


 
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20-Aug-2020 21:34