Query
Also called: query, database query or request
The translation of the English term query is question or search. Searches within Google or a Web site's internal search engine are examples of queries.
Within marketing and ict, a query usually refers to a query within a database. Based on a specified query, the database (or the application communicating with it) returns the corresponding stored information for further processing.
Database queries usually need to be formulated in a specific format. A popular language to describe queries is Structured Query Language (SQL). Common database systems such as Oracle, MySQL and PostgreSQL use this standard or derivatives of it. Queries can be used for reading, adding and editing data as well as for maintaining and managing the format of the database.
In practice, a query to select data from a database consists of:
- An enumeration of the desired fields;
- The table or tables of the database where these fields are located and - in case of multiple tables - the way their records are to be connected;
- Criteria that the fields or records must meet;
- The desired sorting of the result.
In CRM systems, among others, queries can be used to perform complex searches on a customer database. The technology behind many dynamic Web sites and Web applications uses databases and queries to keep information and source code/functionality separate.
