# Chapter 9. Functions and Operators

9.1. Logical Operators
9.2. Comparison Operators
9.3. Mathematical Functions and Operators
9.4. String Functions and Operators
9.5. Binary String Functions and Operators
9.6. Bit String Functions and Operators
9.7. Pattern Matching
9.7.1. ``` LIKE```
9.7.2. ``` SIMILAR TO``` Regular Expressions
9.7.3. POSIX Regular Expressions
9.8. Data Type Formatting Functions
9.9. Date/Time Functions and Operators
9.9.1. ``` EXTRACT``` , ``` date_part```
9.9.2. ``` date_trunc```
9.9.3. AT TIME ZONE
9.9.4. Current Date/Time
9.9.5. Delaying Execution
9.10. Geometric Functions and Operators
9.11. Network Address Functions and Operators
9.12. Sequence Manipulation Functions
9.13. Conditional Expressions
9.13.1. CASE
9.13.2. COALESCE
9.13.3. NULLIF
9.13.4. GREATEST and LEAST
9.14. Array Functions and Operators
9.15. Aggregate Functions
9.16. Subquery Expressions
9.16.1. EXISTS
9.16.2. IN
9.16.3. NOT IN
9.16.4. ANY / SOME
9.16.5. ALL
9.16.6. Row-wise Comparison
9.17. Row and Array Comparisons
9.17.1. IN
9.17.2. NOT IN
9.17.3. ANY / SOME (array)
9.17.4. ALL (array)
9.17.5. Row-wise Comparison
9.18. Set Returning Functions
9.19. System Information Functions