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  2. Referential integrity - Wikipedia

    en.wikipedia.org/wiki/Referential_integrity

    On inserting a new row into the referencing table, the relational database management system (RDBMS) checks if the entered key value exists in the referenced table. If not, no insert is possible. If not, no insert is possible.

  3. Microsoft Office XML formats - Wikipedia

    en.wikipedia.org/wiki/Microsoft_Office_XML_formats

    Besides differences in the schema, there are several other differences between the earlier Office XML schema formats and Office Open XML. Whereas the data in Office Open XML documents is stored in multiple parts and compressed in a ZIP file conforming to the Open Packaging Conventions, Microsoft Office XML formats are stored as plain single monolithic XML files (making them quite large ...

  4. Data independence - Wikipedia

    en.wikipedia.org/wiki/Data_independence

    For example, a change to the internal schema, such as using different file organization or storage structures, storage devices, or indexing strategy, should be possible without having to change the conceptual or external schemas. View level data independence: always independent no effect, because there doesn't exist any other level above view ...

  5. Schema matching - Wikipedia

    en.wikipedia.org/wiki/Schema_matching

    The terms schema matching and mapping are often used interchangeably for a database process. For this article, we differentiate the two as follows: schema matching is the process of identifying that two objects are semantically related (scope of this article) while mapping refers to the transformations between the objects.

  6. Relational schema - Wikipedia

    en.wikipedia.org/wiki/Relational_schema

    The term "schema" refers to the organization of data as a blueprint of how the database is constructed (divided into database tables in the case of relational databases). The formal definition of a database schema is a set of formulas (sentences) called integrity constraints imposed on a database.

  7. Schema migration - Wikipedia

    en.wikipedia.org/wiki/Schema_migration

    Schema migration tools can be said to solve versioning problems for database schemas just as version control systems solve versioning problems for source code. In practice, many schema migration tools actually rely on a textual representation of schema changes (such as files containing SQL statements) such that the version history of schema ...

  8. Schema crosswalk - Wikipedia

    en.wikipedia.org/wiki/Schema_crosswalk

    A schema crosswalk is a table that shows equivalent elements (or "fields") in more than one database schema. It maps the elements in one schema to the equivalent elements in another. It maps the elements in one schema to the equivalent elements in another.

  9. Database schema - Wikipedia

    en.wikipedia.org/wiki/Database_schema

    The database schema is the structure of a database described in a formal language supported typically by a relational database management system (RDBMS). The term " schema " refers to the organization of data as a blueprint of how the database is constructed (divided into database tables in the case of relational databases ).