Start Updating oracle database

Updating oracle database

Since you can't list more than one table in the Oracle UPDATE statement, you can use the Oracle EXISTS clause.

If no default value for the corresponding column has been specified, then the database sets the column to null.

The returning clause retrieves the rows affected by a DML statement.

The only exception to this is if you want to transport tablespaces created previously than Oracle Database 11 Release 1 (11.1) to another platform.

In this case, the file headers must be made read/write at some point before the transport.

You can also perform more complicated updates in Oracle.

You may wish to update records in one table based on values in another table.

The Oracle UPDATE statement is used to update existing records in a table in an Oracle database.

There are 2 syntaxes for an update query in Oracle depending on whether you are performing a traditional update or updating one table with data from another table.

If you omit to indicate that Oracle Database prohibits any changes to the table or view that would produce rows that are not included in the subquery.

When used in the subquery of a DML statement, you can specify this clause in a subquery in the can be a subquery, a column, a function, or a collection constructor.

You can specify this clause for tables and materialized views and for views with a single base table.