Updating a table from a join

06 Jan

When both clauses are used together, the instructs the database to attempt to perform random block sampling instead of random row sampling.

Block sampling is possible only during full table scans or index fast full scans.

The XML string for each output row includes all pivot values found by the subquery, even if there are no corresponding rows in the input data.

The subquery must return a list of unique values at the execution time of the pivot query.

If the subquery does not return a unique value, then Oracle Database raises a run-time error. You can use this clause only if the join columns in both tables have the same name.

You can also implement session-level Flashback using the to retrieve multiple versions of the rows returned by the query.Oracle Database provides a group of version query pseudocolumns that let you retrieve additional information about the various row versions.Refer to "Version Query Pseudocolumns" for more information.Oracle Database returns a set of columns in the order in which the columns were specified when the object was created.A query that selects rows from two or more tables, views, or materialized views is a join.