Not every sheet belongs in the mix
A team has five files about the same shop. One has units as numbers. One has units as words. One is a year out of date.
Blending all five would spoil the result. First decide which data is fit to blend.
Key words
| Word | What it means |
|---|---|
| Dataset | a collection of related data about one subject |
| Data type | the kind of value a column holds |
| Compatibility | how well two datasets can be combined as they are |
| Data profile | a summary of a dataset: counts, gaps and ranges |
| Data quality | how accurate, complete and consistent data is |
| Validation | checking a value is sensible and in the right format |
| Standardise | make values follow one agreed format |
| Key | the column used to match rows |
The cells students fill in are left blank in this preview.
By the end of this lesson
Note
I can assess datasets and choose which data to blend.
Starter
Have a go
Starter
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.
Assess compatibility
Put the datasets side by side. Compare four things: the key column, the other column names, the data type of each column and the format of dates and codes.
Spreadsheets need extra care. A number can be stored as text. A date can be typed three ways.
Two datasets compared
| Check | Sheet A | Sheet B | Compatible? |
|---|---|---|---|
| Key column | product | product | Yes |
| units type | whole number | text | No, convert first |
| Date format | 2026-04-03 | 3 April 2026 | No, standardise |
| Period | April 2026 | April 2025 | No, wrong year |
The cells students fill in are left blank in this preview.
Check
Have a go
Check
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.