[table of contents for nonframes version]

Data Fields

Description

Information in STN records is divided into discrete units called data fields. Examples: author field (contains author information) title field (contains title information) publication year field (contains publication year information)

Synonyms

Field is a synonym for index. For example, 'author field' may also be referred to as 'author index'.

Purpose

Information is divided into data fields to make it possible to target specific kinds of information in a search-related process, and thus make the process more effective. Example: It is possible to search for a title word in just the title field. The ability to add this precision decreases the number of false hits that might occur if the word were searched anywhere in the STN record.

Field Codes

Data fields are identified by mnemonic letter codes. The mnemonic codes are used in search-related processes to designate the data fields. Examples: AU is the code for author field TI is the code for title field PY is the code for publication year field

Data Field Groups

There are 4 different groups of data fields: Display fields Extraction fields Search fields Sort fields Data field groups: Contain many - but not all - of the same data fields Vary by database

Identifying Data Fields

To identify data fields and codes in the current database:

Type	To display a list of
HELP DFIELDS or HELP FORMATS	Display fields and codes Predefined display formats and codes
HELP EFIELDS	Extraction fields and codes
HELP SFIELDS	Search fields and codes
HELP SRTFIELDS	Sort fields and codes

Display Fields

Display fields are those data fields that are displayable. Display formats are predefined combinations of display fields. Display fields and formats are file-specific. Display field codes and display formats are used in the DISPLAY command line to specify the fields of information from a record that you want to view. Type: HELP DFIELDS to identify display fields in the current file HELP FORMAT to identify display formats in the current file HELP DSCAN to identify SCAN options in CA files Display formats and display field codes may be combined. The information is displayed in the order-specified.

Search Fields and Basic Indexes

Search fields are those data fields that are searchable. They are file-specific. Search field codes are used in the SEARCH command line to specify the data fields to be searched. If you do not specify a search field, your term will be searched in the Basic Index of the current database(s). The Basic Index is the default search index of a database. It is generally constructed by merging one or more search fields. For example, the Basic Index of bibliographic databases is typically made up of a combination of the Title, Abstract, and Indexing Term fields. Type HELP SFIELDS for a list of search fields and codes in the current file.

Extraction Fields

Extraction fields are those data fields from which terms can be extracted. They are file-specific. Generally, they are the same as display fields. Extraction field codes are used in the SELECT, ANALYZE, and TRANSFER command lines to designate the data fields of an answer from which terms are to be extracted. Type HELP EFIELDS to identify extraction fields in the current file.

Sort Fields

Sort fields are those data fields that may be sorted. They are file-specific. Sort field codes are used in the SORT command line to rearrange search results in either alphabetic or numeric order by field. Type HELP SRTFIELDS to identify sort fields in the current file.