16. A computer-implemented method of computing a data profile, comprising: estimating a key strength value based on a number of duplicate rows in a data table; computing at least one of exact keys of the data table or approximate keys of the data table based on the key strength value; and generating a pattern profile based on a subset of regular expression patterns that describe patterns in an input set of attribute values from the data table.
16. A computer-implemented method of computing a data profile, comprising: estimating a key strength value based on a number of duplicate rows in a data table; computing at least one of exact keys of the data table or approximate keys of the data table based on the key strength value; and generating a pattern profile based on a subset of regular expression patterns that describe patterns in an input set of attribute values from the data table. 20. The method of claim 16 , further comprising selecting one of the subset of regular expressions as a selected regular expression based on a highest benefit ratio.