| mergeDS {dsBase} | R Documentation |
merges (links) two data.frames together based on common values in defined vectors in each data.frame
mergeDS(
x.name,
y.name,
by.x.names.transmit,
by.y.names.transmit,
all.x,
all.y,
sort,
suffixes.transmit,
no.dups,
incomparables
)
x.name, |
the name of the first data.frame to be merged specified in inverted commas. Specified via argument <x.name> of ds.merge function |
y.name, |
the name of the second data.frame to be merged specified in inverted commas. Specified via argument <y.name> of ds.merge function |
by.x.names.transmit |
the name of a single variable or a vector of names of multiple variables (in transmittable form) containing the IDs or other data on which data.frame x is to be merged/linked to data.frame y. Specified via argument <by.x.names> of ds.merge function |
by.y.names.transmit |
the name of a single variable or a vector of names of multiple variables (in transmittable form) containing the IDs or other data on which data.frame y is to be merged/linked to data.frame x. Specified via argument <by.y.names> of ds.merge function |
all.x |
logical, if TRUE, then extra rows will be added to the output, one for each row in x that has no matching row in y. Specified via argument <all.x> of ds.merge function. Default = FALSE. |
all.y |
logical, if TRUE, then extra rows will be added to the output, one for each row in y that has no matching row in x. Specified via argument <all.y> of ds.merge function. Default = FALSE. |
sort |
logical, if TRUE the merged result should be sorted on elements in the by.x.names and by.y.names columns. Specified via argument <sort> of ds.merge function. Default = TRUE. |
suffixes.transmit |
a character vector of length 2 (in transmittable form) specifying the suffixes to be used for making unique common column names in the two input data.frames when they both appear in the merged data.frame. Specified via argument <suffixes> of ds.merge function. Default '.x' and '.y'. |
no.dups |
logical, when TRUE suffixes are appended in more cases to rigorously avoid duplicated column names in the merged data.frame. Specified via argument <no.dups> of ds.merge function. Default TRUE but was apparently implicitly FALSE before R version 3.5.0. |
incomparables, |
values intended for merging on one column which cannot be matched. See 'match' in help for Native R merge function. Specified via argument <incomparables> of ds.merge |
For further information see details of the native R function merge and the DataSHIELD clientside function ds.merge.
the merged data.frame specified by the <newobj> argument of ds.merge (or by default 'x.name_y.name' if the <newobj> argument is NULL) which is written to the serverside. In addition, two validity messages are returned to the clientside indicating whether <newobj> has been created in each data source and if so whether it is in a valid form. If its form is not valid in at least one study there may be a studysideMessage that can explain the error in creating the full output object. As well as appearing on the screen at run time,if you wish to see the relevant studysideMessages at a later date you can use the ds.message function. If you type ds.message(<newobj>) it will print out the relevant studysideMessage from any datasource in which there was an error in creating <newobj> and a studysideMessage was saved. If there was no error and <newobj> was created without problems no studysideMessage will have been saved and ds.message(<newobj>) will return the message: "ALL OK: there are no studysideMessage(s) on this datasource".
Paul Burton, Demetris Avraam, for DataSHIELD Development Team