OverviewStructured Query Language (SQL) is a specialized language for updating, deleting, and requesting information from databases. SQL is an ANSI and ISO standard, and is the de facto standard database query language. A variety of established database products support SQL, including products from Oracle and Microsoft SQL Server. It is widely used in both industry and academia, often for enormous, complex databases. Show
In a distributed database system, a program often referred to as the database's "back end" runs constantly on a server, interpreting data files on the server as a standard relational database. Programs on client computers allow users to manipulate that data, using tables, columns, rows, and fields. To do this, client programs send SQL statements to the server. The server then processes these statements and returns result sets to the client program. SELECT statementsAn SQL
SELECT column1, column2 FROM table1, table2 WHERE column2='value'; In the above SQL statement:
Note: SQL is not case sensitive (for example, ExamplesFollowing are examples of SQL
To make a
Learning more about SQLTo learn more about SQL programming, Indiana University students, faculty, and staff can download materials for self-study from IT Training. For the general public, various online tutorials are available, such as the w3schools.com SQL Tutorial. This is document ahux in the Knowledge Base. Is a field or set of fields in a record that uniquely identifies the record?A primary key consists of one or more fields that uniquely identify each record that you store in the table. Often, there is a unique identification number, such as an ID number, a serial number, or a code, that serves as a primary key.
What is a collection of fields all related to a single object?A collection of data fields all related to one object, activity, or individual is called a file.
What is a special purpose programming language for accessing and manipulating data stored in a relational database?SQL is a special-purpose programming language designed for managing data stored in a relational database management system. SQL is the language with which a coder communicates with a database to manipulate its data.
Can two sets of fields can have a common primary key?Two sets of fields can have a common primary key. The database approach to managing data is superior to the file-based approach. Today, most organizations use the traditional approach to data management, where multiple information systems share a pool of related data. DBMSs are used primarily for modeling data.
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