InfoTrac Databases: Using Range Operators with Dates

ES-90 - ENVIRONMENTAL RESEARCH METHODS
INFOTRAC DATABASES: SEARCHING: USING RANGE OPERATORS WITH DATES
Syllabus	Schedule	Assignments	Return to Index

DATE LIMITS

Definition

Range operators enable you to specify a range of dates when limiting a search by publication date.

Definition

Publication dates can be entered in a variety of ways (See DATE LIMITS Web page).
In the InfoTrac databases, though publication dates are stored in the following format:
- yyyymmdd, where yyyy = year, m = month, and dd = day

Notes:

Monthlies and bimonthlies have a publication "day" of 00
- Example: 19990100
Annuals store both month and day as zero
- Example: 1990000

OPERATORS

USAGE

since, after, g, >

Use any of these operators to specify that the records that you are searching for must have been published more recently than the date following the operator.

Example: after january 15, 1999

ge

Use this operator to find records that were published on or after the date following the operator.

Example: ge jan 15, 1999

before, l, <

Use any of operators to find records that were published earlier than the date that follows the operator.

Example: before 1/15/1999

le

Use this operator to find records that were published on or before the date following the operator.

Example: le 1/15/1999

to, - (hyphen)

Use any of these operators to specify that the records that you are searching for must have been published between two dates.

Example: da jan 15 - jan 31

Note: If you do not specify a year, the database will assume the current year.

OPERATORS	USAGE
since, after, g, >	Use any of these operators to specify that the records that you are searching for must have been published more recently than the date following the operator. Example: after january 15, 1999
ge	Use this operator to find records that were published on or after the date following the operator. Example: ge jan 15, 1999
before, l, <	Use any of operators to find records that were published earlier than the date that follows the operator. Example: before 1/15/1999
le	Use this operator to find records that were published on or before the date following the operator. Example: le 1/15/1999
to, - (hyphen)	Use any of these operators to specify that the records that you are searching for must have been published between two dates. Example: da jan 15 - jan 31 Note: If you do not specify a year, the database will assume the current year.