How to Select MySQL Columns with Non-Empty Values?

Selecting MySQL Columns with Non-Empty Values

In MySQL, selecting columns based on the presence of data can be achieved using various methods. Consider the task of selecting only rows where a specific column, like 'phone2', contains non-empty values.

To address this, one approach involves comparing the value of 'phone2' with an empty string. The following query demonstrates this:

select phone, phone2 
from jewishyellow.users 
where phone like '813%' and phone2<>''

By comparing 'phone2' with an empty string, the query retrieves rows where 'phone2' has any non-empty value. It's important to note that NULL values are treated as false in this comparison.

This approach provides a straightforward method for selecting rows with non-empty columns, ensuring that the retrieved results meet the desired criteria.

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