WHERE in T-SQL

WHERE in T-SQL: WHERE in T-SQL: an overview, Types of Filters, Using Multiple Condition Filters.

Updated November 3, 2026

1. WHERE in T-SQL: an overview (Novice): A WHERE clause keeps only the rows that match a condition, such as the customers in one country.
2. Types of Filters (Apprentice): Filter numbers and dates with comparison operators, text with LIKE patterns, lists with IN, ranges with BETWEEN, and missing values with IS NULL.
3. Using Multiple Condition Filters (Apprentice): Combine conditions in a WHERE clause with AND, OR and NOT, and use parentheses so they're checked the way you mean.