Range queries

To permit range queries on one or more columns of a database the keyword search_cols should be included in the entry for the database in the configuration file and the %cond keyword should be included in the query part of its url keyword. These items have the following syntax.

search_cols keyword

A list of one or more column names together with text prompts for the minimum and maximum values of the range required.

search_cols: column-name-1 minimum-prompt-1 maximum-prompt-1 :
column-name-2 minimum-prompt-2 maximum-prompt-2 ...

The client uses the minimum and maximum prompts when soliciting the extrema of the required range from the user. An example might be

search_cols: mag "Bright limit" "Faint limit" : ${\tt\backslash}$
b_v "Minimum colour" "Maximum colour"

%cond token

This token is included in the query part of the url keyword and specifies any range search that is supplied. The syntax of the values substututed into the %cond string is:

column-name-1 = minimum-value-1, maximum-value-1& column-name-2 = minimum-value-2, maximum-value-2 ...

When a search is specified column-name-n, minimum-value-n and maximum-value-n are substituted with respectively the column name, minimum value and maximum value. The server should process this string and return only rows that lie within the given ranges. An example of substituted query might be:

mag=1.0,2.0&b_v=0.1,0.3