Overview

Gator provides "Low Limit" and "Up Limit" text fields to specify constraints on a specific query. The formatting rules used in setting these constraints depend on the datatype, as follows:

Character

A character string must be enclosed in a pair of quote; e.g. in "low limit" or "up limit" text fields, type in one of the following:

• ="A"
• >="A"
• <="A"

If the quotes are missing, a syntax error like this will be returned:

201: A syntax error has occurred.

Character data types follow the C convention in interpreting constraints. Check the column description of character datatypes to ensure that meaningful constraints are input.

Example: the MSX6C catalog includes a source name field, called "name", encoded on the basis of the galactic position of the source; e.g. G090.5476+07.9157 is at l=90.5476 and b=+07.9157 in galactic coordinates. Entering this constraint in the upper or lower limit field:

="G090.5476+07.9157"

will retrieve all sources with the name G090.5476+07.9157.

But entering this constraint on the lower limit field:

>"G090.5476+07.9157"

will retrieve all sources with galactic longitudes of greater than 90.4576 degrees.

Numerical (Integer, Float, or Decimal)

Databases generally support a different range of datatypes than do the programming languages with which many users will be familiar. Use the following formatting rules in supplying constraints:

• Treat int and smallint datatypes as integers
• Treat float and smallfloat datatypes as floats.
• Treat decimal datatypes as doubles.

Example constraints:

• =2 (for integer)
• >=2.543 (for float or decimal)

Date

Gator supports only the yyyy-mm-dd format for date datatypes. For example:

= 1996-03-20