If you ever encounter a character column that should be numeric, there’s always a possibility that it contains non-numeric data that you don’t know about.

For example, someone might have set up a Price column as a varchar column that should have been a numeric column, and now you need to clean up after them. You might start by identifying all non-numeric data so that you can work out what to do with it before converting the column to a numeric type.

In SQL, you can run a query to return non-numeric data from the column. The query you use will largely depend on your DBMS.

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If you have a column in a database table that contains character data, but some rows also contain numbers, you can use the following SQL queries to return just those rows that don’t contain numbers within the value.

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Sometimes you might need to search a database table for only those rows that contain at least one number in a given column.

Technically, numbers can be represented by words and other symbols, but here “number” means “numerical digit”.

Below are examples of how to find rows that contain at least one number in various SQL based DBMSs.

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