How do I? > Profile a dataset

In the Right pane you can double click on a column header or click the corresponding button to show a profile of the data in each column. For example the different data types (text, numeric etc) and the frequencies of different values. Potential discrepancies (such as missing values) are highlighted in red.

You can use profiling in conjunction with Filter, Remove Cols and Replace transforms to remove unwanted rows, columns or values; and with the Impute transform to add missing values.

For large datasets you might want to set Sample to less than the full dataset for speed. You can also leave include dates and include statistics unchecked for speed (include dates checks against every date format listed in Preferences).