Search results
Results from the WOW.Com Content Network
In relational databases, a nested table is a table that is embedded within another table.. Individual elements can be inserted, updated, and deleted in a nested table. Since individual elements can be modified in a nested table, they are more flexible than an array because elements in an array can only be modified as a whole, not individually.
Nested tables can be confusing for screen reader users, however with correct usage they can be navigated as well as any other coding approach to the desired display. The key principle in their design and implementation is to maintain normal flow, i.e. to ensure that the ordering of the content in the page code matches the order in which the ...
In 1970, E. F. Codd proposed the relational data model, now [when?] widely accepted as the standard data model. [2] At that time, office automation was the major use of data storage systems, which resulted in the proposal of many UNF/NF 2 data models like the Schek model, Jaeschke models (non-recursive and recursive algebra), and the nested table data model (NTD). [1]
For complex layouts, rowspan and colspan may be used, but again it is sometimes simpler and more maintainable to use nested tables. Nested tables must start on a new line. In the following example, five different tables are shown nested inside the cells of a sixth, main table. None has any header cells.
Text folding is a similar feature used on ordinary text, where the nested elements consist of paragraphs, sections, or outline levels. Programs offering this include folding editors, outliners, and some word processors. Data folding is found in some hex editors and is used to structure a binary file or hide inaccessible data sections. [2]
For example, nested tables (tables inside tables) should be separated into distinct tables when possible. Here is a more advanced example, showing some more options available for making up tables. Users can play with these settings in their own table to see what effect they have.
nested blocks of imperative source code such as nested if-clauses, while-clauses, repeat-until clauses etc. information hiding: nested function definitions with lexical scope; nested data structures such as records, objects, classes, etc. nested virtualization, also called recursive virtualization: running a virtual machine inside another ...
A derived table is the use of referencing an SQL subquery in a FROM clause. Essentially, the derived table is a subquery that can be selected from or joined to. The derived table functionality allows the user to reference the subquery as a table. The derived table is sometimes referred to as an inline view or a subselect.