Rlabkey (version 3.3.0)

getLookups: Get related data fields that are available to include in a query on a given query object

Description

Retrieve a related query object referenced by a lookup column in the current query

Usage

getLookups(session, lookupField)

Value

A query object representing the related data set. The fields of a lookup query object are usually added to the colSelect parameter in getRows, If a lookup query object is used as the query parameter in getRows, the call will return all of the base query columns and all of the lookup query columns. A lookup query object is very similar to base query objects that are named elemenets of a schema object, A lookup query object, however, does not have a parent schema object, it is only returned by getLookups. Also, the field names in a lookup query object are compound names relative to the base query object used in getLookups.

Arguments

session

the session key returned from getSession

lookupField

an object representing a lookup field on LabKey Server, a named member of a query object.

Author

Peter Hussey

Details

Lookup fields in LabKey Server are the equivalent of declared foreign keys

References

https://www.labkey.org/Documentation/wiki-page.view?name=propertyFields

See Also

getSession, getRows getSchema

Examples

if (FALSE) {

##  get fields from lookup tables and add to query
# library(Rlabkey)

s<- getSession(baseUrl="http://localhost:8080/labkey",
    folderPath="/apisamples")
 
scobj <- getSchema(s, "lists")

# can add fields from related queries
lucols <- getLookups(s, scobj$AllTypes$Category)

# keep going to other tables
lucols2 <- getLookups(s, lucols[["Category/Group"]])

cols <- c(names(scobj$AllTypes)[2:6], names(lucols)[2:4])

getRows(s, scobj$AllTypes, colSelect=paste(cols, sep=","))

}