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Data control language. (Redirected from Data Control Language) A data control language (DCL) is a syntax similar to a computer programming language used to control access to data stored in a database (authorization). In particular, it is a component of Structured Query Language (SQL). Data Control Language is one of the logical group in SQL ...
Cerner CCL (Cerner Command Language) is the Cerner Corporation fourth-generation programming language, which is expressed in the Cerner Discern Explorer. [1] CCL is patterned after the Structured Query Language (SQL). All Cerner Millennium health information technology software uses CCL/Discern Explorer to select from, insert into, update into ...
Tuple relational calculus. Tuple calculus is a calculus that was created and introduced by Edgar F. Codd as part of the relational model, in order to provide a declarative database-query language for data manipulation in this data model. It formed the inspiration for the database-query languages QUEL and SQL, of which the latter, although far ...
SQL syntax. The syntax of the SQL programming language is defined and maintained by ISO/IEC SC 32 as part of ISO/IEC 9075. This standard is not freely available. Despite the existence of the standard, SQL code is not completely portable among different database systems without adjustments.
Data query language (DQL) is part of the base grouping of SQL sub-languages. These sub-languages are mainly categorized into four categories: a data query language (DQL), a data definition language (DDL), a data control language (DCL), and a data manipulation language (DML). Sometimes a transaction control language (TCL) [ 1 ] is argued to be ...
A query plan (or query execution plan) is a sequence of steps used to access data in a SQL relational database management system. This is a specific case of the relational model concept of access plans. Since SQL is declarative, there are typically many alternative ways to execute a given query, with widely varying performance.
SQL was initially developed at IBM by Donald D. Chamberlin and Raymond F. Boyce after learning about the relational model from Edgar F. Codd [12] in the early 1970s. [13] This version, initially called SEQUEL (Structured English Query Language), was designed to manipulate and retrieve data stored in IBM's original quasirelational database management system, System R, which a group at IBM San ...
To SELECT one row of data from a table called tab with a primary key column (pk) set to 100 — use the condition pk = 100: SELECT * FROM tab WHERE pk = 100. To identify whether a table tab has rows of data with a duplicated column dk — use the condition having count (*) > 1: SELECT dk FROM tab GROUP BY dk HAVING count(*) > 1.