enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Data definition language - Wikipedia

    en.wikipedia.org/wiki/Data_definition_language

    The ALTER statement modifies an existing database object. An ALTER statement in SQL changes the properties of an object inside of a relational database management system (RDBMS). The types of objects that can be altered depends on which RDBMS is being used. The typical usage is: ALTER objecttype objectname parameters.

  3. SQL syntax - Wikipedia

    en.wikipedia.org/wiki/SQL_syntax

    Title Authors ----- ----- SQL Examples and Guide 4 The Joy of SQL 1 An Introduction to SQL 2 Pitfalls of SQL 1 Under the precondition that isbn is the only common column name of the two tables and that a column named title only exists in the Book table, one could re-write the query above in the following form:

  4. Identity column - Wikipedia

    en.wikipedia.org/wiki/Identity_column

    An identity column differs from a primary key in that its values are managed by the server and usually cannot be modified. In many cases an identity column is used as a primary key; however, this is not always the case. It is a common misconception that an identity column will enforce uniqueness; however, this is not the case. If you want to ...

  5. Oracle Database - Wikipedia

    en.wikipedia.org/wiki/Oracle_Database

    Oracle Database 23ai LTR: 23.4.0 On May 2, 2024, Oracle Database 23ai [10] was released on Oracle Cloud Infrastructure (OCI) as cloud services, including OCI Exadata Database Service, OCI Exadata Database Cloud@Customer, and OCI Base Database Service. It is also available in Always Free Autonomous Database.

  6. Null (SQL) - Wikipedia

    en.wikipedia.org/wiki/Null_(SQL)

    In SQL, null or NULL is a special marker used to indicate that a data value does not exist in the database. Introduced by the creator of the relational database model, E. F. Codd , SQL null serves to fulfill the requirement that all true relational database management systems ( RDBMS ) support a representation of "missing information and ...

  7. Oracle 10g - Wikipedia

    en.wikipedia.org/wiki/Oracle_10g

    As of the Oracle Database 10g release, Oracle Corporation seems to have started to make an effort to standardize all current versions of its major products using the "10g" label. Major products include: Oracle Database 10; Oracle Application Server 10g (aka Oracle AS 10g) — a middleware product

  8. PL/SQL - Wikipedia

    en.wikipedia.org/wiki/PL/SQL

    Oracle Corporation usually extends PL/SQL functionality with each successive release of the Oracle Database. PL/SQL includes procedural language elements such as conditions and loops, and can handle exceptions (run-time errors). It allows the declaration of constants and variables, procedures, functions, packages, types and variables of those ...

  9. SQL - Wikipedia

    en.wikipedia.org/wiki/SQL

    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 ...