CaseExpression
            
Functions selecting a value conditionally
Contents
| Name | Description | 
|---|---|
| Case abbreviation COALESCE | Returns the first operand that is not equal to NULL. If all operands are NULL then returns NULL | 
| Case abbreviation NULLIF | Returns NULL if the operands are equal otherwise returns the first operand | 
| Searched case | Selects one from a number of alternate values | 
| Simple case | Selects one from a number of alternate values |