•Use parallel instance recovery by setting RECOVERY_PARALLISM.•Increase PARALLEL_EXECUTION_MESSAGE_SIZE from its default of 2,148 bytes to 4 KB or 8 KB. This should provide better recovery slave performance.•Set PARALLEL_MIN_SERVERS to CPU_COUNT-1. This will prespawnrecovery slaves at startup time.•Using asynchronous I/O is one of the most crucial factors in recovery time. The first-pass log read uses asynchronous I/O.•Instance recovery uses 50 percent of the default buffer cache for recovery buffers. If this is not enough, some of the steps of instance recovery will be done in several passes. You should be able to identify such situations by looking at your alert.logfile. In that case, you should increase the size of your default buffer cache.
Today, all company needs to save data and information, these kinds of data different from company to other such as (pictures, employee and Customer data); it’s so rarely to find companies used papers to save important data.We don’t disagree on database type, Sure Oracle is the best but there’s another product in the market today such as Oracle, Microsoft and k2 but all these products have common thing Called Threats .
Before this, we need to know what we mean with database Security since it’s my article subject
Database Security: can be defined as a system or process by which the “Confidentiality, Integrity, and Availability (CIA) of the database can be protectedUnauthorized entry or access to a database server signifies a loss of confidentiality; unauthorized alteration to the available data signifies loss of integrity; and lack of access to database services signifies loss of availability. Loss of one or more of these basic facets will have a significant impact on the security of the database.
This is the common defined for database security.For an illustration of this concept, imagine that the website of a company contains information like who they are, what they do, and what prospective customers have to do to contact them for their queries. In this case, the availability of the database services is more important when compared with other factors like the confidentiality or integrity of the database security.
Threats and risks to databases have increased and therefore, the need for securing databases has also increased. When it comes to securing a database, lots of things have to take care of , if you was focused On pervious talking you will know that I am talking about:
What I mean in this word is so simple by encrypting the data stored in the database,two type of encryption in database :
This refers to data that is moving within the network. Sensitive data, for example, that is sent through network layers or through the Internet. A hacker can gain access to this sensitive data by eavesdropping. When this happens, the confidentiality of the data is compromised. Encrypting datain-transit avoids such compromises.
It is possible for a hacker to hack the data that is stored in the database. Encrypting data-at-rest prevents such data leakages.
I am not going to say it’s too simple to, because I don’t want from Listeners to kick me; but guys for me It’s simple sorry, Integrity talking about which users have to be given what permissions in the database For example, data related to employee information is stored in a database. An employee may have permission for viewing the records and altering only part of information like his contact details, whereas a person in the human resources department will have more privileges.
To make sure everything is going to be ok just following these steps:
- Change the password, once the database is installed.
- Policies to set strong passwords have to be enforced. A good idea is to have a policy of changing the passwords once per a month.
- Does your company have multiple database administrators? If yes, segregate the duties
among these database administrators.
Simple steps (again simple) save you and your company.
Now last but I am not finished yet
Databases must not have unplanned downtime, to ensure this, following steps have to be taken:
- To ensure high availability, usage of database clusters is recommended.
- Databases should be secured against security vulnerabilities.
- Backup the data at periodic intervals to ensure data recovery in case of application issues.
As we all know there’s nothing perfect so when we talk about Security, that mean we talk about Threats and attackers. With the increase in usage of databases, the frequency of attacks against those databases has also increased; Database attacks are an increasing trend these days. What is the reason behind database attacks? One reason is the increase in access to data stored in databases. When the data is been accessed by many people, the chances of data theft increases. In the past, database attacks were prevalent, but were less in number as hackers hacked the network more to show it was possible to hack and not to sell proprietary information. Another reason for database attacks is to gain money selling sensitive information, which includes credit card numbers, Social Security Numbers, etc. We previously defined database security and talked about common database security concepts. Now let’s look at the various types of threats that affect database security.
Written By : Osama Mustafa
Consider this as part one since i will post another one related to this .