Conditional

The e6 Ingestion Engine scalar functions are based on Apache DataFusion and these docs are derived from the DataFusion function reference.

Function	Description	Example	Result
coalesce(e1, ..., en)	First non-null value	coalesce(NULL, NULL, 'hello')	'hello'
nullif(e1, e2)	NULL if e1 = e2	nullif(5, 5)	NULL
nvl(e1, e2)	e2 if e1 is NULL	nvl(NULL, 'default')	'default'
nvl2(e1, e2, e3)	e2 if e1 not NULL, else e3	nvl2('x', 'yes', 'no')	'yes'

coalesce

Returns the first of its arguments that is not null. Returns null if all arguments are null. This function is often used to substitute a default value for null values.

coalesce(expression1[, ..., expression_n])

Arguments

• expression1, expression_n: Expression to use if previous expressions are null. Can be a constant, column, or function, and any combination of arithmetic operators. Pass as many expression arguments as necessary.

nullif

Returns null if expression1 equals expression2; otherwise it returns expression1. This can be used to perform the inverse operation of coalesce.

nullif(expression1, expression2)

Arguments

• expression1: Expression to compare and return if equal to expression2. Can be a constant, column, or function, and any combination of arithmetic operators.
• expression2: Expression to compare to expression1. Can be a constant, column, or function, and any combination of arithmetic operators.

nvl

Returns expression2 if expression1 is NULL; otherwise it returns expression1.

nvl(expression1, expression2)

Arguments

• expression1: return if expression1 not is NULL. Can be a constant, column, or function, and any combination of arithmetic operators.
• expression2: return if expression1 is NULL. Can be a constant, column, or function, and any combination of arithmetic operators.

nvl2

Returns expression2 if expression1 is not NULL; otherwise it returns expression3.

nvl2(expression1, expression2, expression3)

Arguments

• expression1: conditional expression. Can be a constant, column, or function, and any combination of arithmetic operators.
• expression2: return if expression1 is not NULL. Can be a constant, column, or function, and any combination of arithmetic operators.
• expression3: return if expression1 is NULL. Can be a constant, column, or function, and any combination of arithmetic operators.

ifnull

Alias of nvl.