Hola, continuando con esta serie de post relacionados con la encriptación de datos dentro de la base de datos SQL Server y utilizando las mismas herramientas que el motor de base de datos, en este articulo cubriremos la encriptacion en base a un certificado. Read more »

FORCESEEK obliga al optimizador de consultas a usar sólo una operación de Index Seek como ruta de acceso a los datos de la tabla o vista a la que se hace referencia en la consulta.
Comentaros que el operador Index Seek utiliza la capacidad de búsqueda de los índices para recuperar filas de un índice… Al forzar una operación de index seek, se puede lograr un mejor rendimiento de las consultas.
FORCESEEK puede invalidar el plan predeterminado elegido por el optimizador de consultas para evitar problemas de rendimiento producidos por un plan de consultas ineficaz.
Por ejemplo, si un plan usa un índice, y las tabla correspondiente a ese plan produce un número alto de lecturas durante la ejecución de la consulta, una de las cosas que podemos hacer, para determinar si el plan de ejecución usado por una consulta es el adecuado, antes de la ejecución de la consulta ejecutamos: Read more »

This study is made with PostgreSQL 9.1.1, released a couple of days before this post is written.
Unlogged tables are a new performance feature of PostgreSQL 9.1, created by Robert Hass. So, by guessing from this feature name, those tables are not logged in the database system . More precisely, those tables do not use at all WAL (Write ahead log) that insure a safe database crash.
Those tables are a good performance gain to contain data that do not especially need to survive from a crash, they are truncated automatically after a crash or unclean shutdown.
Unlogged tables are shared among sessions, and are not deleted when a session ends. Autovacuum runs on them. Read more »

In most release notices, it’s the big shiny sexy features that get all the glamor, but in reality on day to day use it’s the small usability enhancements that make the most difference. I’m reminded about this now that I’m working on upgrade scripts and extensions for PostGIS. There are a couple of new features that make application upgrades easier that I regret not having in older versions of PostgreSQL we support and additional ones I had in other databases that I find lacking in PostgreSQL. PostgreSQL 8.2 for example brought us DROP IF EXISTS … and all I can say is thank goodness we dropped support of prior versions of PostgreSQL in PostGIS 1.4 otherwise developing upgrade scripts would have been more of a nightmare. PostgreSQL 8.4 introduced the ability to add additional columns to a view using CREATE OR REPLACE VIEW as long as those columns were at the end of the view which Gabrielle Roth demonstrates an example of in This week’s find: CREATE OR REPLACE VIEW If you were a MySQL user or application developer not having such features would be one reason to frown on PostgreSQL and MySQL users and other database converts still have reasons to frown for lack of usability features they had in their other database that they feel naked without in PostgreSQL.
In 9.1 we got two new DDL commands not much talked about that I am very excited about. Read more »

Problem:
On starting ET-Connector, the drivers for the following databases cannot be found:
ORACLE
DB2
PostgreSQL Read more »

Firebird Project is happy to announce general availability of Firebird 2.5.1 – a minor release of the award-winning relational database management system.
This sub-release introduces several bug fixes and many important improvements – for example, performance improvements during a database restore, the ability to write to global temporary tables in read-only databases, etc.
For the full list of changes please refer to the Release Notes, Chapter 2 “New in Firebird 2.5″. Firebird 2.5.1 has 100% compatible on-disk structure with Firebird 2.5.0, so it is recommended to migrate to 2.5.1 as soon as possible. To download Firebird 2.5.1, please visit the download section at the official web-site: www.firebirdsql.org. Read more »