Detail When Querying Databases, You've Got to Ask The Right Question   Oleh:  Hunton, James E. ; Hayes, David C. Jenis: Article from Bulletin/Magazine Dalam koleksi: Journal of Accountancy vol. 191 no. 2 (2001), page 35-48. Topik: database; querying databases; right question Ketersediaan Perpustakaan Pusat (Semanggi) Nomor Panggil: JJ85.12 Non-tandon: 1 (dapat dipinjam: 0) Tandon: tidak ada     Lihat Detail Induk Isi artikel The power of relational databases lies not so much in their ability to store vast amounts of information, but in their capacity to sort out complex data relationships and then assemble custom reports on them. Thus, for example, a database that contains customer names and sales information can report which customers bought a particular product and any number of other relationships that link them. The key, however, is knowing how to ask the right questions of the database, and this article shows how. In relational database jargon, a question is called a query and represents a request for information from tables in one or more databases. When a query is posed and the data sorted, the underlying database doesn’t change. The software just looks into the tables, searches for and processes the requested relationships and then issues the customized answers, leaving the original data untouched. Most applications built on relational databases incorporate a querying tool known as query - by - example (QBE), which uses a graphical approach to construct queries. Although QBE tools are visual and relatively easy to use, they’re somewhat limited. To create complex queries, especially when dealing with multiple databases, users must turn to a language called structured query language (SQL) or structured English query language. The acronym for both is pronounced sequel. In today’s world of client - server architecture and data warehouses, it’s important to understand the fundamentals of SQL, for it is the basis of all database queries. We’ll build queries using the QBE feature of Microsoft Access and briefly explain the SQL code underlying each request. Opini Anda Klik untuk menuliskan opini Anda tentang koleksi ini! Kembali

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