StreamSQL Conditional Functions

Conditional functions are used for conditional judgment and value selection.

IF_NULL - Null Handling Function

Syntax: if_null(value, default_value)
Description: If the value is NULL, returns the default value; otherwise returns the original value.

COALESCE - Coalesce Function

Syntax: coalesce(value1, value2, ...)
Description: Returns the first non-NULL value.

NULL_IF - Null Conversion Function

Syntax: null_if(value1, value2)
Description: If the two values are equal, returns NULL; otherwise returns the first value.

GREATEST - Greatest Function

Syntax: greatest(value1, value2, ...)
Description: Returns the maximum value among the parameters.

LEAST - Least Function

Syntax: least(value1, value2, ...)
Description: Returns the minimum value among the parameters.

CASE_WHEN - Conditional Branch Function

Syntax: case_when(condition, value_if_true, value_if_false)
Description: Returns different values based on the condition.

📚 Related Documentation

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• SQL Reference - View complete SQL syntax reference