Is the syntax valid if it checks for a user with the "IS" operator?

The "IS" operator is typically used in SQL and other programming contexts to evaluate whether a value is a specific type or matches a specific condition, such as checking for null values with "IS NULL." However, using the "IS" operator to check for a user or a specific user enumeration might not align with standard usage where conditions are typically checked using comparison operators or membership tests (like "IN" or "EXISTS").

In most programming and query languages, checking the existence of a specific user would be more appropriately accomplished using operators like "=", which directly compares two values, or using functions tailored to user authentication or validation. Thus, relying on the "IS" operator in this context would likely lead to syntax errors or unintended behavior, confirming that the syntax isn't valid for checking a user directly.