Data

Question 1

TIDY data

Answer 1

Filter
Transform
Aggregate
Sort
Join/Merge (Inner/Outer)

Question 2

Common Data Problems

Answer 2

In different source systems
Messy:
Missing
Invalids
Errors
Different levels

Question 3

Common Data Types

Answer 3

Flat File
-Not used as much now
-Each field is placed in a fixed position (e.g. first 5 bytes of the file)
CSV
-Values are separated by commas (very common as many systems can export a CSV
Delimited File
-Pipe (example is Air BnB)
-Tab, etc.
Proprietary (e.g. SAS, SPSS, Workday etc.)