Learn SQL Database Programming

Detecting duplicate and erroneous values

To see duplicate values in a table, execute the following query:

USE lahmansbaseballdb;SELECT name_fullFROM schoolsGROUP BY name_fullHAVING count(*) >= 2;

The preceding query gives you the results shown in the following screenshot:

These are possible duplicates. If you execute the following query, you will see be able all the fields in the table to see if they are genuinely duplicates:

USE lahmansbaseballdb;SELECT * FROM schoolsWHERE name_full = 'Bethel College'; 

The preceding query gives you the results shown in the following screenshot:

You can see that these aren't duplicates since they each ...