☛ Separate data depending on their attributes

☛ In the case of massive datasets, do a stepwise cleansing and improve on the data on every step until the data quality is good.

☛ For common data cleansing, you need to generate a set of scripts which include blanking out every value not matching a regex.

☛ Do analysis on the statistic for every column.

☛ Stay up to date with all cleaning operations, so changes could make when necessary.