Solving Data Quality issues on SQL DB

Hi Everyone

I have a dataset with some data quality issues. I am given a task to find out the data quality issues and provide a solution then analysis and insight.

This is for my interview on Monday which I have been waiting for this opportunity for 13 years almost. That's why I want to do my best .

I listed and group the data quality issues then solved them in Excel as data set is provided in Excel. However I want to make a presentation and talk about the fix this issues in SQL database where data is extracted from.

I made my notes regarding the data type issues however I am not expert about SQL database structure.

May I please ask your help to review my notes in Data Quality issues tab in attached spreadsheet and if possible add your comments on what amendments needs to be made in SQL database to solve these issues?

Original Data which is not cleaned is in Data tab.

Really appreciate for your help in advanced.

Kind Regards
B.