WHERE - Stockful

WHERE keeps only the rows that match your conditions, before any grouping or totalling happens. A condition compares a field to a value, and you can chain conditions with AND and OR.

FROM sales
  SHOW total_revenue, units_sold
  WHERE vendor = 'Nike' AND units_sold > 0

Operators

Operator	Meaning
`=`	Equal to
`!=`	Not equal to
`<` `>` `<=` `>=`	Less than, greater than, and the “or equal to” forms
`IN (...)`	Matches any value in a list
`NOT IN (...)`	Matches none of the values in a list
`IS NULL` / `IS NOT NULL`	Tests for a missing value
`LIKE`	Matches text against a pattern, where `%` is a wildcard
`CONTAINS`	Matches text that contains a substring

Text values go in single quotes. A list uses parentheses, for example reason IN ('too small', 'damaged'). You can also compare one field to another, such as available < reorder_point.

FROM returns
  SHOW units_returned, return_rate
  WHERE reason IN ('too small', 'damaged') OR reason IS NULL

Named filters

Some datasets offer named filters that stand in for a common condition. On the inventory dataset, for example, low_stock selects items running low on cover, and needs_reorder selects items the reorder engine recommends buying now. Write the name on its own, and combine it with other conditions using AND.

FROM inventory
  SHOW current_quantity, days_of_supply
  WHERE low_stock AND vendor = 'Nike'

AND binds tighter than OR. Use parentheses to group conditions when you mix the two. To filter on totals after grouping instead, use HAVING.