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Databases

Lester Tay
Lester Tay
416 Points

Using SQL to find out all columns containing empty cells

This is a question from SQL basics but I can't seem to return to the course upon completion (can anyone teach me how to do it?)

Also, would like to ask if we want to use SQL to find out all the columns with empty cells, do we type: SELECT * FROM <sheet> WHERE <column 1> IS NULL OR <column 2> IS NULL ….<column n> IS NULL; ???

Seems like an ineffective method to me especially if there are many columns.

Thank you very much.

1 Answer

Steven Parker
Steven Parker
216,057 Points

From your home page, if you select "Completed" on the courses bar you should then be able to select any course you've finished and re-enter it.

Your code for selecting rows with empty columns seems correct and would probably be reasonably efficient even if the code itself is somewhat verbose. SQL is often like that.