#MySQL运算符

-- Calculate totals

-- Calculate discounts

-- Average calculation

-- Equality

-- Inequality

-- Greater than

-- Range queries

-- Case-sensitive comparison (binary)

-- Case-insensitive comparison

-- Pattern matching

-- AND operator

-- OR operator

-- NOT operator

-- Combined logic

-- AND with NULL

-- Use IS NULL

-- NULL-safe comparison

-- Bitwise AND

-- Bitwise OR

-- Bitwise XOR

-- Left shift

-- Case-sensitive comparison

-- LIKE pattern matching

-- Concatenation operator (deprecated)

-- CONCAT function (recommended)

-- Match pattern

-- Match specific position

-- Regular expression match

-- Not match

-- Inclusive range

-- Date range

-- Equivalent to AND

-- Multiple values

-- Subquery

-- NOT IN

-- Test for NULL

-- Test for not NULL

-- Combined with other conditions

-- NULL-safe equality

-- NULL-safe inequality

-- Precedence matters
-- Without parentheses
-- With parentheses

-- Complex expression
-- Evaluates as: price * (quantity * discount)
-- Should be: (price * quantity) * discount

-- Set variable

-- Multiple assignments

-- Conditional assignment

-- Age categorization

-- Price range classification

-- Pattern matching

-- Combined conditions

-- Complex expressions