Techniques are described herein for indexing personal information in columnar data storage format based files. In an embodiment, row groups of rows that comprise a plurality of columns are stored in a set of files. Each column of a row group is stored in a chunk of column pages in the set of files. A regular expression index that indexes a particular column in the set of files is stored for each row group. The regular expression index identifies column pages in the chunk of the particular column that include a particular column value that satisfies a regular expression specified in a query. The regular expression specified in the query in evaluated against the particular column using the regular expression index.