Joins in NoSQL database

Joins are hard to do in any distributed database. Even on distributed Sql databases. It is not that joins cannot be supported in a NoSql database. It is just that the database is not designed to be efficient for joins (I’ll explain why), and hence there is no point in supporting joins. Because if you

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Key-value database

A key-value database, or key-value store, is a data storage paradigm designed for storing, retrieving, and managing associative arrays, a data structure more commonly known today as a dictionary or hash. Dictionaries contain a collection of objects, or records, which in turn have many different fields within them, each containing data. These records are stored

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Database optimization

While certain queries may, by their very nature, require little or no cost estimation or comparison between plans to determine optimum performance, most queries will benefit from full optimization. One of the most beneficial methods for increasing the performance of queries is the creation of efficient indexes. A well-constructed index will allow a query to

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Database transaction

A transaction symbolizes a unit of work performed within a database management system (or similar system) against a database, and treated in a coherent and reliable way independent of other transactions. A transaction generally represents any change in a database. Transactions in a database environment have two main purposes: To provide reliable units of work

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RDBMS architecture

The design of a DBMS depends on its architecture. It can be centralized or decentralized or hierarchical. The architecture of a DBMS can be seen as either single tier or multi-tier. An n-tier architecture divides the whole system into related but independent n modules, which can be independently modified, altered, changed, or replaced. In 1-tier

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Database relationships

Database relationships are associations between tables that are created using join statements to retrieve data. The following table describes the database relationships. Type of relationship Description One-to-one Both tables can have only one record on each side of the relationship. Each primary key value relates to none or only one record in the related table.

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Data integrity

Data integrity is a fundamental component of information security. In its broadest use, “data integrity” refers to the accuracy and consistency of data stored in a database, data warehouse, data mart or other construct. The term – Data Integrity – can be used to describe a state, a process or a function – and is

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ER Model

The ER model defines the conceptual view of a database. It works around real-world entities and the associations among them. At view level, the ER model is considered a good option for designing databases. Entity An entity can be a real-world object, either animate or inanimate, that can be easily identifiable. For example, in a

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Database Normalization

Normalization is the process of efficiently organizing data in a database. There are two goals of the normalization process: eliminating redundant data (for example, storing the same data in more than one table) and ensuring data dependencies make sense (only storing related data in a table). Both of these are worthy goals as they reduce

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