La capacidad de gestionar y analizar grandes volúmenes de datos es esencial para la competitividad de cualquier empresa. El software de base de datos y las plataformas de datos proporcionan el soporte necesario para integrar, almacenar y procesar información de manera ágil y segura.

En Dataprix hemos elaborado nuestro TOP 10 de software o plataforma de datos, una clasificación que reúne las soluciones más destacadas del mercado en términos de rendimiento, escalabilidad, seguridad e integración. Descubre las 10 herramientas que están transformando la gestión de datos en las empresas.

In SQL Server, to delete records from a table following a criterion that is related to another table in the database you can establish a join between the two tables in the same SQL Delete statement.

In SQL Server, to delete records from a table following a criterion that is related to another table in the database you can establish a join between the two tables in the same SQL Delete statement.

If we want to make a record delete using a join we must specify in the first line of the statement the table in which we want to apply the deletion of records, and in the next line the join of the tables we need, and the criterion indicated with a where..

DB2, from version 9.7, allows to know easily what indexes are not being used in a Database. The query is also for tables and packages.

This is a useful tool for tuning indexes and detecting problems in their use.

After version 9.7 DB2 includes a new LASTUSED field in the SYSCAT.INDEXES, SYSCAT.TABLES and SYSCAT.PACKAGES tables.

This field indicates the date of last use of indexes, tables or packages.

For example, to query unused indexes since 1/1/2019, you could use this simple query:

In this tables, I relate general terminology, versions, utilities and views from IBM DB2 and Oracle databases..

This mini tip show you how to know when was the last time you restart a DB2 server on a UNIX / LINUX.

> db2 get snapshot for dbm | grep Start

Start Database Manager timestamp = 04/02/2011 13:45:20.516473

Simple, isn't it?

Db2look is an utility to extract the definition of database objects. It also allows some really interesting statistics to extract objects for export to other test environments / integration plans and get the same access to objects.

In this article we will see more frequent usefulness.

DDL extraction of the objects in my schema:

db2look -d MI_BBDD -a -e -x -o FICHERO_SALIDA.txt

Extraction of the DDL of the DEPT table:

db2look -d MI_BBDD -t DEPT -a -e -x -o FICHERO_SALIDA.txt

To include statistics to have to use the “-m” option.

Below are a list with the more common status of IBM DB2 tablespaces

The most used method to show the status of the tablespaces is, from the console command line:

The cache hit ratio is one of the indicators used for tuning tasks. It Measures the percentage of hits in memory, specifically in the bufferpools (each of them).

To get the cache hit ratio for each buffer pool configured to run this query:

SELECT SUBSTR(DB_NAME,1,8) AS DB_NAME, SUBSTR(BP_NAME,1,14) AS BP_NAME,
TOTAL_HIT_RATIO_PERCENT, DATA_HIT_RATIO_PERCENT,
INDEX_HIT_RATIO_PERCENT
FROM SYSIBMADM.BP_HITRATIO ORDER BY DBPARTITIONNUM