"recovery value" field name not found error occurs

[pandya__01]

("VolumeFlowRate (Clean) at Reverse Osmosis1 Outlet (Segment1) [m3/h]"/"VolumeFlowRate at RO1 Inlet (Segment1) [m3/h]") AS "recovery value",
(1/(1-"recovery value")) as rec_value

[vinieme12]

You cannot refer a column that is being calculated in the same load , simply because it does not exists until it has been loaded

You have 3 options 

1) repeat the calculation for recovery value 

(1/1- ("VolumeFlowRate (Clean) at Reverse Osmosis1 Outlet (Segment1) [m3/h]"/"VolumeFlowRate at RO1 Inlet (Segment1) [m3/h]")) as rec_value

2)Use preceding load 

Tablename:

Load 

*,

(1/(1-"recovery value")) as rec_value;

Load 

("VolumeFlowRate (Clean) at Reverse Osmosis1 Outlet (Segment1) [m3/h]"/"VolumeFlowRate at RO1 Inlet (Segment1) [m3/h]") AS "recovery value"

From xxxxxxx;

3)Use resident load 

Temp:

Load 

("VolumeFlowRate (Clean) at Reverse Osmosis1 Outlet (Segment1) [m3/h]"/"VolumeFlowRate at RO1 Inlet (Segment1) [m3/h]") AS "recovery value"

From xxxxxxx;

FinalTable:

Load 

*,

(1/(1-"recovery value")) as rec_value

Resident Temp;

Drop table Temp;

[vinieme12]

https://youtu.be/Q6CQQ4QCu78 

https://qlikviewcookbook.com/2016/04/the-cost-of-preceding-load/