Preview: Oracle NoSQL database

Over the past few years, the world of NoSQL databases has been filled with interesting new projects, ambitious statements and a lot of promises. It is rumored that the latest NoSQL database software package achieves significant performance improvements by adjusting all the structures and the three times-fold checksum that the database creator has been hoping to increase over the years. What about reliability? The reliability is overrated, according to Wall Street programmers who didn't use the NoSQL database to run large-scale enterprise applications but only trivial deals. What about the tabulation structure? Too rigid and limited. If we ignore these issues, then the advantages of the database are free and run fast.

The NoSQL database is also very slow to be published. Oracle-the top research and development firm in the Advanced NoSQL database has launched a reliable and practical NoSQL server that is very similar to Oracle's. While frantic dreamers continue to build repositories of NoSQL databases, they think they want to focus on Oracle's version. Not only does it offer many features that make NoSQL databases more interesting, but reliable performance claims to come from a large team of engineers.

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The advent of the product may surprise the NoSQL database enthusiasts (those who have been proud of the Oracle database), but Oracle will slow down the road for the time being. Oracle acquired the SLEEPYCAT software company five years ago, the founder of the Open-source Beckley database (a long and traditional tool for the flexibility of key value storage designed for C and later Java programmers). The same Beckley database technology is said to be at the heart of Oracle's NoSQL database, although it seems that all the code needs to be rewritten.

Oracle NoSQL Database: Practical acid

The interesting point of Oracle NoSQL database is the key value structure. You don't need to define a plan or stick to a large tabular architecture. You only need to create a key value and associate it with the byte. You can connect your key values to a string or image file or anything. The database can receive bytes and does not need to consider too much content.

Oracle divides key values into major and minor parts. You can consider the main part as the goal indicator, and the secondary part as the field in the record. This allows you to place the name and social Security number in the main part of the key value, and other strings such as street address and zip code are placed in the secondary section. and other NoSQL tools can be compared to help users consider the value of multiple domain objects. Oracle only uses the data "secondary key values" as the name of the domain.

Oracle NoSQL database is an important part of a practical acid,nosql database that may be available in standard editions. Acid is a "subtle, consistent, independent, durable treatment" that is hotly debated in detail. Most NoSQL database promises are "base", the initials of "basic usability, soft state and final consistency." In other words, you can get the right answer, unless you don't need it.

There is a lot of debate about whether Oracle NoSQL databases can provide real acid. You can only get acid commitments when you write data that correlates to the main part of the same key value. For example, since both parts are stored in the same key value, you can change the address and zip code of the same person and get an acid guarantee. But there is no guarantee that the changes of two independents will remain consistent. In other words, banks have been able to use Oracle NoSQL databases to store personal records, but they will not be used for secure transactions in cash between accounts, as there is no acid guarantee that will not result in pecuniary loss.

Oracle NoSQL Database can make this commitment because it ensures that a primary function stores all secondary key values associated with the primary key value. Associates a collection of any fields to the primary key value that defines a person, and all of this data is concentrated on the same node of the cluster. But data from different key values is placed on different servers, and Oracle NoSQL databases do not have a mechanism to ensure that data is written to both primary and secondary key values.

You can also add copies and fragments, which Oracle calls "zoning." In essence, it is the node that arranges fragments in the matrix. If you need more reliability and faster reading speed, you need to add more systems along the copy axis. If you want to reduce the controversy, you can add more systems along the partition axis. Oracle NoSQL Database can handle more of these configurations for you.

This is more than a binary judgment. You can let Oracle NoSQL database to terminate the write, or most nodes have finished sending data to the hard disk. The file describes this feature as a persistence agreement.

This flexibility can also be used by programmers, if you have time to worry about it. All key value pairs are accompanied by a version number. This is helpful if you want to improve performance when modifying records.

Sustainability: Controversial

Daniel Abadi, a professor at the Department of Computational Science at Yale University, has sparked controversy over the ultimate sustainability. Abadi points out that in some cases, a new pairing written to the primary key value may be lost after the primary key is cut off. Saircha, a professor of computer science at Harvard University and Oracle's employee, holds a different view. She joined the acquired Sleepycat company.

Saircha that everything depends on your understanding of "ultimate sustainability." The database owner chooses to take advantage of their chances of continuing the agreement. If the owner wants to ensure that a pairing is not lost, they must all write the data until all replicas have been upgraded.

To test the speed of Oracle's NoSQL database, the authors used a low-end test to put more pressure on the database engine than on the network. The author starts with a single node NoSQL server, and then tries 358,400 key values associated with the key value (just red contains a string of about 30 characters), and the speed is 119 seconds on older Mac computers. Old-Model devices using small-capacity random memory are a way to test performance under limited resources.

In contrast, the author has the same pairing test the new version of Voldemort, this is a LinkedIn from the Java-developed open source NoSQL database. Spent 180 seconds on the same device.

Since storing data in Oracle NoSQL database may seem to involve some administrative expenses, the author has only done some simple tests. Create a key value that needs to build a sequence of strings, and the target instance is usually the bottleneck of Java code. None of these tests seem to pose a problem.

In general, Oracle's NoSQL database is willing to try because it provides such a rich feature for more in-depth data management. Tools are more thorough and time-tested than simple nosql projects. In the face of node failure, you have different options to improve endurance.

Oracle NoSQL database may not be a surprise to you, but it can only accumulate experience with open source NoSQL projects, but it's not really the role. Oracle has learned the best ideas to deliver the best performance to the enterprise market.

Oracle NoSQL databases are separated from the long tradition of oracle bones. The author finds it difficult to install and run the Oracle main database. In contrast, the open source community can do better. There are users who say that the most important MySQL is better at testing and testing the installation configuration.

Oracle's NoSQL database is clearly from a research and development team with open source traditional experience. The only problem is encountered when the local host is changed to 127.0.0.1. This is a big improvement.

(Responsible editor: The good of the Legacy)