Where Shipped IS NULL - SQL for Data Analysis

IS NULL is SQL's explicit missing-value test for NULL cells.

highlighted = computed this step

Input table

Start with shipments where some shipped dates are NULL.

\text{Shipments}

Use IS NULL to test for missing shipped dates explicitly.

\text{WHERE shipped date IS NULL}

NULL shipped dates evaluate to TRUE; known dates evaluate to FALSE.

\text{IS NULL truth check}

Only rows with missing shipped dates pass the WHERE filter.

\text{missing shipped dates}