Condiciones compuestas. Condiciones de rango. Condiciones nulas. IS ANY. IS OF type. Consultas distribuidas dblinks. Tipo de dato CHAR b. Tipos de objetos Long y Raw. URI Factory Package. URI type. Joaquin Gonzalez 7 marzo, am Reply. Hola Javier, He intentado reproducir el problema y no aparece. Javier Morales 7 marzo, am Reply. Vamos a ver: 1. Yo tampoco puedo reproducir el error ahora. No existe el problema si se da grant directo al usuario, y no al role y este al usuario.
Andrew Reid 28 febrero, pm Reply. Hola Javier, Espero que estas bien. Tal vez tengo una respuesta a este problema. Un Saludo Andrew. Javier Morales 3 marzo, am Reply. Hola Andrew! If the materialized view is dropped, then the preexisting table reverts to its identity as a table. This is the default. Restrictions on Using Prebuilt Tables Prebuilt tables are subject to the following restrictions:. Each column alias in subquery must correspond to a column in the prebuilt table, and corresponding columns must have matching datatypes.
If you specify this clause, then you cannot specify a NOT NULL constraint for any column that is not referenced in subquery unless you also specify a default value for that column.
If you omit this clause, then Oracle Database creates the materialized view in the default tablespace of the schema containing the materialized view. The default is the logging characteristic of the tablespace in which the materialized view resides. In such a materialized view, data rows are stored in an index defined on the primary key of the materialized view. You can specify index organization for the following types of materialized views:. Read-only and updatable object materialized views.
You must ensure that the master table has a primary key. Restrictions on Index-Organized Materialized Views Index-organized materialized views are subject to the following restrictions:. A cluster materialized view uses the space allocation of the cluster. Use these property clauses to describe a materialized view that is not based on an existing table. Partitioning of materialized views is the same as partitioning of tables.
For data that will be accessed frequently, CACHE specifies that the blocks retrieved for this table are placed at the most recently used end of the least recently used LRU list in the buffer cache when a full table scan is performed.
This attribute is useful for small lookup tables. The first deferred refresh must always be a complete refresh. Oracle Database uses the default index to speed up incremental FAST refresh of the materialized view. If the master tables of a materialized view are modified, then the data in the materialized view must be updated to make the materialized view accurately reflect the data currently in its master tables.
This clause lets you schedule the times and specify the method and mode for the database to refresh the materialized view. Specify FAST to indicate the incremental refresh method, which performs the refresh according to the changes that have occurred to the master tables. The changes for conventional DML changes are stored in the materialized view log associated with the master table. No user intervention is needed.
Materialized views are not eligible for fast refresh if the defining query contains an analytic function. Oracle Database Advanced Replication for restrictions on fast refresh in replication environments. Oracle Data Warehousing Guide for restrictions on fast refresh in data warehousing environments. If you request a complete refresh, then Oracle Database performs a complete refresh even if a fast refresh is possible.
Specify FORCE to indicate that when a refresh occurs, Oracle Database will perform a fast refresh if one is possible or a complete refresh if fast refresh is not possible. Specify ON COMMIT to indicate that a fast refresh is to occur whenever the database commits a transaction that operates on a master table of the materialized view. Para determinar que necesita la vista materializada para ser fast refreshed se pude utilizar un query como el siguiente:.
Algunos ejemplos:. Los momentos en los que usarlas pueden ser:. Muchas gracias. Recibir nuevas entradas por email. Cuando se crea la vista materializada, la query se ejecuta y el resultado se inserta en la tabla contenedora.
Fast Refreshes con Materialized View Logs En un fast refresh, el contenido de la tabla contenedora es reutilizado y solo se propagan las modificaciones de la tabla base a la tabla contenedora. Share this: Twitter Facebook.
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