SQL(ID:533/sql001)

for Structured Query Language.

IBM, 1970's, for use in System R. The de facto standard relational database interface language, often embedded in other programming languages.

It allows us to pose complex questions of a database. Also provides a means of creating databases. If you know SQL, you can apply this knowledge to MS Access, SQL server, Oracle, or Ingres and countless other databases. Works with relational databases (stores data in tables, relations).  

Structures:
Related languages
SEQUEL => SQL   Evolution of
SQL => CORAL   Derivation of
SQL => Lisp/sql   Incorporated some features of
SQL => RPL   Based on
SQL => SQL 92   Evolution of
SQL => SQL/NF   Alias
SQL => UDL   Negative Mild Influence
References:
  • Denny, G.H. "An introduction to SQL, a structured query language". Rep. RA 93, IBM Research, San Jose, Calif., May 1977. view details
  • Lacroix, Michale; and Pirotte, Alain "Domain-oriented relational languages" view details
          in Proceedings of the 3rd conference on very large data bases (Tokyo, Japan, Oct. 6-8, 1977), IEEE, New York, ACM, New York, 1977 view details
  • Lomet, D., review of Lacroix and Pirotte 1978 view details Extract: Review
    This paper introduces a different approach to defining query languages called "domain oriented." Domains are defined independently of relations, e.g., a COMPANY domain might be ("AMC," "CHRYSLER," "FORD," "GM," "VW"). The relations become ways of building associations between the entities of the domains. Many query languages such as, for example, SQL, SQUARE,. TAMALAN have a tuple-oriented approach. This approach introduces tuple variables and name qualification within a tuple. The domain-oriented approach avoids this but involves heavier quantification.
    Based on the domain-oriented approach and a domain relational calculus, an "English-like" language called ILL (Intermediate Level Language) is defined. Care has been taken to guarantee that ILL is "wholly built on a structure of expressions nested inside other expressions...." This is, of course, generally useful to assure expressive power and flexibility, independent of any English-like attribute. The hypothesis of the paper is that the domain-oriented approach has a closer similarity to English than the tuple-oriented approach. This is supported by a number of examples which contrast ILL with the tuple-oriented language SEQUEL (now called SQL).
    Certain constructs are not included in ILL in order to retain its English-like quality. This seems unfortunate. A construct can frequently be useful without being English-like. It is, or should be, well known that some queries are difficult to express in English, particularly those in which negation and quantification interact. The ILL language becomes somewhat complicated here as well.
    Actually, both tuple- and domain-oriented approaches are useful in different circumstances. Perhaps what is needed is a query language that permits a natural integration of both approaches. In any event, the domain-oriented approach is a nice way of handling many queries. This paper presents the idea in a clear and well organized way. It is well worth studying.
    D. Lomet, Yorktown Heights, N. Y.

          in ACM Computing Reviews 20(09) September 1979 view details
  • SHARE DBMS Language Task Force. "An Evaluation of Three COBOL Data Base Languages -- UDL, SQL, and CODASYL." Proc. SHARE 53 (August 1979). view details
          in ACM Computing Reviews 20(09) September 1979 view details
  • C. Welty et al, "Human Factor Comparison of a Procedural and a Non-procedural Query Language" view details Abstract: Two experiments testing the ability of subjects to write queries in two different query languages were run. The two languages, SQL and TABLET, differ primarily in their procedurality; both languages use the relational data model, and their Halstead levels are similar. Constructs in the languages which do not affect their procedurality are identical. The two languages were learned by the experimental subjects almost exclusively from manuals presenting the same examples and problems ordered identically for both languages. The results of the experiments show that subjects using the more procedural language wrote difficult queries better than subjects using the less procedural language. The results of the experiments are also used to compare corresponding constructs in the two languages and to recommend improvements for these constructs.
          in ACM Trans Database Sys 6(4) (Dec 1981) view details
  • Meersman, R., "The high-level end user", Starlab Report 1982 view details pdf Abstract: A rapid development is taking place in the area of database query languages and relevant aspects of a query language are considered. The classification of query languages, according to certain criteria, is discussed. Reference and Idea Language (RIDL) from Control Data is examined in detail and its role as a semantic network language is assessed in relation to a database containing information of aircraft
    types. IBM's Structural English Query Language (SQL), developed for use on a relational DBMS, is also examined and compared with RIDL. Conceptual and usage differences are discussed and similarities assessed.
          in ACM Trans Database Sys 6(4) (Dec 1981) view details
  • Martin, James "4GL Fourth-Generation Languages Volume III, 4GLs from IBM" James Martin Englewood Cliffs, New Jersey: Prentice Hall, 1986 view details
          in ACM Trans Database Sys 6(4) (Dec 1981) view details
  • Date, C.J. "A Guide to the SQL Standard," A-W 1987. view details
          in ACM Trans Database Sys 6(4) (Dec 1981) view details
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