Can I use… nullif(…, …)

SQL nullif returns the value of the first argument unless it equals the second argument—then it returns the null value.

SELECT NULLIF(int_expression, 0)
  FROM …

The example returns the value of int_expression unless it contains the the value zero (0)—then it returns the SQL null value. This particular example is useful to prevent division by zero errors.

Related

• Tutorials

  • NULL in SQL: Indicating the Absence of Data

  • case — Conditional Expressions

• Other conditional expressions:

  • case … when … (simple)

  • case when … (searched)

  • coalesce(…, …[, …]*)

  • case … when <op> … (extended)

  • case … when …, … (comma-separated)

Normative References

The nullif expression is defined in ISO/IEC 9075:2016-2 as mandatory feature F261-03.