Oracle 9i Tutorial : UPDATE Statement Syntax

UPDATE Statement Syntax

Update Statement is used to modify existing rows in table.

Below is Update State Syntax :

UPDATE  table

SET  column = value [, column = value, ...]

[WHERE   condition];

In the syntax:

  table  is the name of the table

  column  is the name of the column in the table to populate

  value  is the corresponding value or subquery for the column

  condition  identifies the rows to be updated and is composed of column names   expressions, constants, subqueries, and comparison operators

Updating Rows in a Table

•Specific row or rows are modified if you specify the WHERE clause.

   •All rows in the table are modified if you omit the WHERE clause.

 

Updating Rows Based on Another Table

You can use subqueries in UPDATE statements to update rows in a table. The example on the slide updates the COPY_EMP table based on the values from the EMPLOYEES table. It changes the department number of all employees with employee 200’s job ID to employee 100’s current department number.