Expression error

[Nspiler]

I am using the following to establish a new conditional column in Power Query:

= Table.AddColumn(#"Filtered Rows3", "LC19", each
if[FY18]= #date(2017, 7, 1) and [FY19] = #date(2018, 7, 1) then "Retained"
else
if[FY19]= #date(2018, 7, 1) and [First Gift Date]>= #date(2018, 7, 1) then "New"
else
if[FY18]= #date(null) and [FY19]= #date(2018, 7, 1) and [First Gift Date]<= #date(2017, 6,30) then "Reactived"
else "N/A")

And I keep receiving the folowing Expression.Error: 1 arguments were passed to a function which expects 3.
Details:
Pattern=
Arguments=[List]

All the referenced columns are formatted as type Date - what am I missing?

[Omid_Motamedise · Accepted solution]

Instead of using 

if[FY18]= #date(null)

Use

if[FY18]= null

[v-prasare]

@Nspiler, Thanks for reaching out ot MS fabric community support.

@ronrsnfld, @Omid_Motamedise, @rohit1991, @Fowmy  Thanks for your promt response. @Nspiler Can you please confirm whether solution provided by our super worked for you? please let us know if you need further assistance.

Your feedback is important to us, Looking forward to your response. 

Thanks,

Prashanth Are
MS fabric community support

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[ronrsnfld · Accepted solution]

To explain further, your error message is because:

#date(year, month, day) requires three arguments.

#date(null) has only one argument

Of course, #date(null,null,null) would also be invalid as the arguments for #date(...) need to be of type number and each within a certain range of numbers, and null cannot be converted to a number. 

As others have pointed out, you can just use if [FY18]=null ...

[Omid_Motamedise · Accepted solution]

Instead of using 

if[FY18]= #date(null)

Use

if[FY18]= null

[rohit1991]

Your issue is caused by using #date(null), which is invalid. Replace it with null for null checks. Here's the corrected code:

= Table.AddColumn(#"Filtered Rows3", "LC19", each
if [FY18] = #date(2017, 7, 1) and [FY19] = #date(2018, 7, 1) then "Retained"
else if [FY19] = #date(2018, 7, 1) and [First Gift Date] >= #date(2018, 7, 1) then "New"
else if [FY18] = null and [FY19] = #date(2018, 7, 1) and [First Gift Date] <= #date(2017, 6, 30) then "Reactivated"
else "N/A"
)

[Fowmy]

@Nspiler 

in the following line, you have used #date(null) which is not acceptable, try this way

if [FY18]= null and [FY19]= #date(2018, 7, 1) and [First Gift Date]<= #date(2017, 6,30) then "Reactived"

You may try [FY18]= "" also