The performance of an Oracle database and SQL query speed can directly affect the organisation it belongs to. If the queries running in the database are slow, they will surely have a negative impact. However, its severity may vary based on the database’s role, its architecture, and the industry your organisation operates in.
Regardless of the extent, it would be unwise to ignore them, which is why we are going to talk about all their effects in this blog.
How Slow Statements Affect Oracle Database and SQL Users
In this fast-paced world, everything needs to work fast and offer a quick response time to its end-users. The data that a web page displays generally comes directly from the database with very few interactions.
This implies the dependency of the application’s response time on the time it takes for the queries to run and the database to respond. Slow statements will take more time, resulting in loading screens before the desired information shows up. This is when Oracle database performance tuning becomes a requirement.
Such speeds don’t affect only the application, however; they leave an impact on the other parts of a system as well. The reason behind this is the location of the database in a majority of web architectures.
Take a look at the three-tier architecture, for example – the database lies at the bottom in most cases, forming the foundation. An increase in latency here is likely to cause the same in the higher levels along with other areas in the system.
Another way in which slow queries negatively impact the system is by making the database use more resources than is actually necessary. Some of these are available in limited quantities, such as I/O and CPU, since other applications share these resources.
On the other hand, not using existing resources sufficiently leads to their inefficient usage and slow queries as well. This may be the case with your database, so you may want to consider a few Oracle performance tuning tips that deal with this particular issue.
Top Reasons Behind Slow and Inefficient Queries
Given below are the three most significant causes of queries slowing down:
- Too many tasks: Executing a statement includes multiple tasks, such as retrieving data, making calculations, and arranging data in the order as the query specifies. All of these involve plenty of factors, any of which can increase the amount and complexity of work done, from joining and grouping to filtering and sorting.
- Too much waiting: Sometimes, statements don’t have too much to do, nor are they stuck waiting for resources. The reason why they are sluggish is that they are waiting on other statements that are locking resources or requiring higher levels of activity.
- Too few resources: Query execution works alongside other tasks taking place within a system. This means they share resources such as network throughput, disk I/O, and CPU. Statement execution is likely to take more time when these are completely occupied.
Locating and Working on Slow Queries in Oracle Database
Slow queries don’t get faster on their own – DBAs must take steps to speed them up. For starters, they can use the Database Performance Monitor (DPM) in the following ways:
- Viewing all the queries that are taking up execution time using the query profiler. Such queries are often running in the absence of indexes, so it’s a good idea to add one to improve Oracle database performance and execution speed.
- Automatically collecting explain plans to get a quick glance at the ones that contain information regarding slow queries and the changes related to them, if any.
- Assessing Oracle database and SQL to find out whether a statement can perform better with the help of some improvements.
- Visiting the charts page to go through properly arranged metrics pertaining to system performance. This allows the DBA to set a threshold alert and note changes every time a system resource is reaching maximum use.
Based on your architecture and application, slow statements can affect more aspects of your business than just the database. Therefore, ignoring them is not recommended as it often results in a detrimental impact on both end-users and your organisation.
Consider enlisting the help of professional tuning tools to improve slow query performance in Oracle and SQL Server databases.