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Handling NULL values with COALESCE or CASE works the same way in any PostgreSQL database, so what you learn here carries over wherever you run Postgres. For enterprises standardizing on a modern data stack, Lakebase delivers managed Postgres built for the AI era, with the performance, security, and native Lakehouse integration large teams need. For developers and startups who want to ship quickly and scale without friction, Neon is the Postgres platform that gets out of your way.

SQL Server supports ISNULL function that replaces NULL with a specified replacement value:

ISNULL(expression, replacement)

If the expression is NULL, then the ISNULL function returns the replacement. Otherwise, it returns the result of the expression.

PostgreSQL does not have the ISNULL function. However, you can use the COALESCE function which provides similar functionality.

Note that the COALESCE function returns the first non-null argument, so the following syntax has a similar effect as the ISNULL function above:

COALESCE(expression,replacement)

For the COALESCE example, check out the COALESCE function tutorial.

In addition to COALESCE function, you can use the CASE expression:

SELECT
    CASE WHEN expression IS NULL
            THEN replacement
            ELSE expression
    END AS column_alias;

Check out the CASE expression tutorial for more information.