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# ifn()

Here’s how to use ifn() function.

## A .ifn()

Description:

Get the first non-null member of a sequence.

Syntax:

 A.ifn() Equivalent to ifn(x1,…,xn)

Note:

The function gets the first non-null member of sequence A.

Parameter:

 A A sequence with the length of n

Return value:

The first non-null member of the sequence.

Example:

 A 1 =[1,2,4].ifn() 1 2 =[null,2,3,4].ifn() 2 3 =[null,2,null,4].ifn() 2 4 =ifn(null,1,2,4) 1

Related function:

## A. ifn( x )

Description:

Compute x with each member of the sequence and return the first non-null member of the new sequence.

Syntax:

 A.ifn(x) Equivalent to A.(x).ifn()

Note:

The function loops through members of sequence A to compute expression x and return the first non-null member of the new sequence.

Parameter:

 A A sequence x Generally an expression of a single field name, or a legal expression composed of multiple field names

Return value:

The first non-null member of the new sequence

Example:

 A 1 =demo.query("select * from EMPLOYEE") 2 =A1.ifn(SALARY) Return the first non-null value of SALARY 3 =A1.(SALARY+100).ifn() Add 100 to the salary of each employee and return the salary of the first employee

Related function: