sql-servert-sqlcastingintegerisnumeric

T-sql - determine if value is integer

I want to determine if a value is integer (like TryParse in .NET). Unfortunatelly ISNUMERIC does not fit me because I want to parse only integers and not every kind of number. Is there such thing as ISINT or something?

Here is some code to make things clear. If MY_FIELD is not int, this code would fail:

SELECT @MY_VAR = CAST(MY_FIELD AS INT)
FROM MY_TABLE
WHERE MY_OTHER_FIELD = 'MY_FILTER'

Thank you

Solution

  • Here's a blog post describing the creation of an IsInteger UDF.

    Basically, it recommends adding '.e0' to the value and using IsNumeric. In this way, anything that already had a decimal point now has two decimal points, causing IsNumeric to be false, and anything already expressed in scientific notation is invalidated by the e0.