F

Field:

Tables are divided into fields and records. Fields impose structure and data type specifics onto each of the field values in a record. Fields can even be used to attach some processing to (specific to that field). Changes can be used to trigger events to occur.

Field List:

This is the part of a SELECT command listing fields to be retrieved by an SQL query. When more than one field is retrieved then the fields become a list of fields, or field list.

File System:

A term used to describe the files in a database, or on a server computer, at the operating system level.

Filter:

See Filtering .

Filtered Query:

See Filtering .

Filtering:

Retrieve a subset of records, or remove a subset of records from a data source. Filtering is done in SQL using the WHERE clause for a basic query of records retrieved, and using the HAVING clause to remove groups from an aggregated query.

Flat File:

A term generally applying to an unstructured file, such as a text file.

Flattened Structure:

This generally refers to a database model structure consisting of one, or at most very few, hierarchical layers. For example, a data warehouse star schema consists of fact tables and some dimension tables (all on the same level). The result is only two levels, flattened out from a normalized (multiple layered) table structure of an OLTP database. Some applications and databases, when working with XML, do not have the capability to deal with XML object-hierarchical structure, and tend to flatten out XML documents into one or two hierarchical layers .

Float Data Type:

A floating point data type allows a number where the floating point can be anywhere in the number. Mathematically, a floating-point number is a real number.

Floating Point:

A real number where the decimal point can be anywhere within the number.

FLWOR:

See XQuery FLWOR .

For Loop:

A programming looping construct used to execute a sequence of programming or scripting commands a specified number of times.

Foreign Key:

A foreign key is a type of constraint where foreign key columns contain copies of primary key values, uniquely identified in parent entities, representing the child or sibling side of what is most commonly a one-to-many relationship.

Fragment:

A small section of an XML document, consisting of properly formed XML. A fragment could be the entire XML document, or a small subtree (node and all children) of an XML document.

FROM Clause:

The part of a query SELECT command that determines tables (or other data source) to be retrieved from. The FROM clause can also be used to syntactically describe and dictate how tables are joined (using the JOIN , ON , and USING clauses).

Front End:

Customer- facing software usually applications purchased either online over the Internet, or in-house as custom written applications.

Function:

A function is a programming unit or expression returning a single value, also allowing determinant values to be passed in as parameters. Thus, parameter values can change the outcome or return result of a function. The beauty of a function is that it is self contained and can thus be embedded into an expression.