How Can I Check if a MySQL Value is an Integer?

Determining the Integer Nature of MySQL Values

In MySQL, determining whether a value is an integer is crucial for data validation and manipulation. This question explores methods to check the integer status of a value, similar to the is_int() function in PHP.

Solution 1: Regular Expression Matching

If you need to check a string value, a convenient approach is to use the REGEXP operator. This operator enables you to match the string against a regular expression pattern. To check for integers, employ the following regular expression:

^-?[0-9]+$

This pattern matches strings representing integers, both positive and negative. By using the query:

select field from table where field REGEXP '^-?[0-9]+$';

you can retrieve only the integer values from the field.

Solution 2: Numeric Comparison

For numeric fields, a simpler solution is to capitalize on the fact that integer values are expressed as whole numbers without a fractional part. You can compare the ceiling of the field to the field itself:

ceil(field) = field

If the comparison evaluates to true, the field contains an integer. This method avoids the computational overhead of regular expressions.

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