The OUTALL= data set combines and expands the information provided by the OUTCONT= and OUTBY= data sets. That is, the OUTALL= data set not only reports the OUTCONT= information separately for each BY group, but also reports the OUTBY= information separately for each series. Each observation in the OUTBY= data set gets expanded to NSERIES or NSELECT observations in the OUTALL= data set, depending on whether the OUTSELECT=OFF option is specified.
By default, only the selected BY groups and series are included in the OUTALL= data set. If the OUTSELECT=OFF option is specified, then all the series within all the BY groups are reported.
The OUTALL= data set contains all the variables defined in the OUTBY= and OUTCONT= data sets and also contains the GENERIC variables (whose values can vary from one series to another and from one BY group to another). Another additional variable is BLKNUM, which gives the data block number in the data file containing the series variable.
The OUTALL= data set is useful when BY groups do not contain the same time series variables or when the time ranges for series change across BY groups.
You should be careful in using the OUTALL= option, since the OUTALL= data set can get very large for many file types. Some file types have the same series and time ranges for each BY group; the OUTALL= option should not be used with these file types. For example, you should not specify the OUTALL= option with COMPUSTAT files, since all the BY groups contain the same series variables.
The OUTALL= and OUTCONT= data sets are equivalent when there are no BY variables, except that the OUTALL= data set contains extra information about the time ranges and observation counts of the series variables.