官术网_书友最值得收藏!

History of SQL/TSQL

During the seventies, the IBM research centre in San Jose, California created a research team named System R based on Edgar F. Codd's article A Relational Model of Data for Large Shared Data Banks. This later evolved into IBM System/38 in August of 1978. In 1986, the language SQL (Structured Query Language), became an ANSI standard and in 1987 it was accepted as an ISO standard. Today, almost 40 years later, SQL is de facto standard when we are talking about retrieving and data processing.

In order to successfully write queries against SQL Server databases, you need to understand the query language T-SQL (Transact-Structured Query Language). T-SQL, and both the ANSI and ISO standard, offers words such as SELECT, INSERT, UPDATE, and DELETE as well as FROM, JOIN, WHERE, GROUP BY, and ORDER BY to understand the syntax and what these words add to build better results when querying the database.

Even if the standards have minimal support for flow control, T-SQL offers additional scripting and batch processing flow control support such as IF...ELSE, WHILE.

主站蜘蛛池模板: 体育| 蒙阴县| 东阿县| 辉县市| 赤峰市| 江陵县| 阿瓦提县| 越西县| 盐山县| 昌邑市| 耒阳市| 岐山县| 台州市| 汕头市| 峨边| 兴和县| 双辽市| 进贤县| 册亨县| 兰州市| 和田市| 贡觉县| 那坡县| 陵川县| 波密县| 稻城县| 常德市| 高青县| 乐业县| 项城市| 新沂市| 布拖县| 克东县| 句容市| 阿克苏市| 拉萨市| 黄平县| 乐平市| 会昌县| 西吉县| 平塘县|