Class aRTquerier

Description

Class that manipulates the result of a query in a database. It returns the objects one by one, and can slide a temporal aRTtheme. This class is different from the others because it does not store anything in the database.

Objects from the Class

obj = new("aRTquerier", parent,... ) Objects can be created by calls of the form openQuerier(parent, loadgeom=T, loadatt=T), or openQuerier(theme, chronon="hourofday").

Arguments

parent:

Object of class {aRTlayer,aRTtheme}

loadgeom:

Will geometry be retrieved?

loadatt:

Will attributes be retrieved?

chronon:

A temporal slicing.

table:

(not implemented)

att:

(not implemented)

stat:

(not implemented)

Chronon

• nochronon
• second
• minute
• hour
• day
• month
• year
• dayofweek
• dayofmonth
• dayofyear
• monthofyear
• season
• weekofyear
• hourofday
• minuteofhour
• secondofminute

Stat

• nostat
• sum
• max
• min
• count
• validcount
• stddev
• kernek
• mean
• variance
• skewness
• kurtosis
• median
• varcoeff
• mode

Extends

Class aRTcomponent, directly.

Methods

getData:

Returns the next element of the query result in the actual slide.

nextSlide:

Loads the next slide, if there is a temporal sliding. A temporal query needs to load one slide before using getData for getting its elements. Non-temporal queries can't use this function. Note that you can do a non-temporal query in a temporal layer.

Author(s)

Pedro Ribeiro de Andrade Neto