根据上文“What is a database? A database is a collection of data or information that is organized, stored, and accessed electronically.(什么是数据库?数据库是用电子方式组织、存储和访问的数据或信息的集合)”以及后文“There are three main distinguishing aspects of any database(任何数据库都有三...
informationyou find on the internet and that in databases is that the information found in databases is often confirmed." (你在互联网上找到的信息和在数据库中找到的信息之间的一个主要区别是,在数据库中找到的信息通常是经过证实的。)可知,本段在讲数据库的可靠性。A项"它是可靠的"可以作为本段主旨句...
A database is a logical grouping of data. It contains a set of related table spaces and index spaces. Typically, a database contains all the data that is associated with one application or with a group of related applications. You could have a payroll database or an inventory database, f...
A database primary key is a column or combination of columns which uniquely identifies each row in a table. As long as you have unique primary keys, you also have unique rows, which makes it possible to uniquely identify every row in a table. Question: Why is this so important? This...
What is Database? ADVERTISEMENT Adatabaseis an organized collection of data, so that it can be easily accessed and managed. You can organize data into tables, rows, columns, and index it to make it easier to find relevant information. ...
Akey-value databaseis a type of non-relational database, also known asNoSQL database, that uses a simple key-value method to store data. It stores data as a collection of key-value pairs in which a key serves as a unique identifier. Both keys and values can be anything, ranging from...
A database schema defines how data is organized within a relational database; this is inclusive of logical constraints such as, table names, fields, data types and the relationships between these entities. Schemas commonly use visual representations to communicate the architecture of the database, ...
identifier as the primary key such as an employee ID, a part number, or a customer number. The primary key is typically the column used to maintain each record's unique identity among the tables in a relational database. Databases allow you to use multiple columns for the primary key. ...
A graph database is defined as a specialized, single-purpose platform for creating and manipulating graphs. Graphs contain nodes, edges, and properties, all of which are used to represent and store data in a way that relational databases are not equipped to do. Graph analytics is another commo...
Choosing the primary key in a database is one of the most important steps in the process. It can be a normalattributethat is guaranteed to be unique such as Social Security number on a table with no more than one record per person or — preferably — it can be generated by the databa...