How to Select Only Columns with Non-Empty Values in MySQL?

MySQL: Selecting Columns with Non-Empty Values

In MySQL, you can select specific columns only if they contain non-empty values. This allows you to filter out any rows where those columns are null or empty.

Example Query

Consider the following query:

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

Here, the goal is to select rows where:

• phone starts with '813'
• phone2 contains a non-empty value

Solution

To select columns only where non-empty values exist, you can compare the value of the column with an empty string.

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

Explanation

• phone like '813%': Filters rows where phone starts with '813'.
• phone2<>'': Checks if phone2 is not equal to an empty string, effectively filtering out empty values.

Note: Null values are interpreted as false in MySQL. This means that rows with phone2 set to null will not be included in the results.

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