How to Identify Null, Empty, or Whitespace-Only Columns in MySQL?

How to Determine Column Emptiness in MySQL

Checking for empty or null values in MySQL tables is crucial for ensuring data integrity. This is especially relevant when dealing with columns that accept blank or null data.

Problem:

Consider a table with a column that may contain null or empty values. The goal is to identify rows where this column is devoid of data or contains whitespace. This would encompass cases like null, empty strings ('') as well as leading or trailing white spaces (' ').

Solution:

MySQL provides a convenient way to check for both null and empty string values in a single query:

SELECT * FROM table WHERE some_col IS NULL OR some_col = '';

In this query, the IS NULL condition checks for null values, while the some_col = '' condition identifies empty strings. By combining these conditions using the OR operator, you can retrieve all rows where the some_col column is either null or empty.

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