Explanation
Data Cleaning means correcting or removing inaccurate, incomplete, duplicated, or inconsistent data so that it can be used reliably for analysis.
Common data problems:
- Duplicate records
- Extra spaces
- Inconsistent spelling
- Blank cells
- Incorrect data types
- Incorrect capitalization
- Unwanted characters
Example
|
Customer |
City |
Sales |
|
Amit |
Sirsa |
4000 |
|
Amit |
Sirsa |
4000 |
|
Neha |
Hisar |
5000 |
|
Rahul |
SIRSA |
25500 |
|
Priya |
Fatehabad |
24000 |
Problems include:
- Duplicate Amit record
- SIRSA vs Sirsa
- Extra spaces around Priya
Practice
Identify all data-quality problems in the table.