Azure Data Factory
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ADF Error when using function from Data Flow Library
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Luis Trujillo
20
Reputation points
I have the following function in my data flow library:
iif(isDecimal(i1),toDecimal(i1,i2,i3), toDecimal('0.00',i2,i3))
Configuration:
When running the data flow i get this error:
Cannot evaluate constant value with this type
If I removed i2 and i3 the function works, any ideas why?
Azure Data Factory
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Bhargava-MSFT 31,261 Reputation points Microsoft Employee Moderator2024-07-11T23:20:55.98+00:00 Hello Luis Trujillo,
The error message "Cannot evaluate constant value with this type" suggests that the function is expecting a constant value, but is receiving a different type instead.
As i2 and i3 are of type integral, you should make sure these values are explicitly set to integers when used in the toDecimal function.
iif(isDecimal(i1), toDecimal(i1, toInteger(i2), toInteger(i3)), toDecimal('0.00', toInteger(i2), toInteger(i3)))By using toInteger() around i2 and i3, we make sure that the parameters are explicitly cast to integers.
You can also test your expression with a hardcoded values:
iif(isDecimal("123.45"), toDecimal("123.45", 5, 2), toDecimal('0.00', 5, 2))If you still encounter issues, please provide more details on the values being passed to
i1,i2, andi3, as well as any additional details of your data flow setup.I hope this helps.
If this answers your question, please consider accepting the answer by hitting the Accept answer and up-vote as it helps the community look for answers to similar questions.
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Luis Trujillo 20 Reputation points
2024-07-11T23:33:50.96+00:00 I tried your expression, same error:
iif(isDecimal(i1),toDecimal(i1,toInteger(i2),toInteger(i3)), toDecimal('0.00',toInteger(i2),toInteger(i3)))
The expression is being call from a flowlet as:
MapDecimal(sltchg,9,2)
If I hardcode i2 and i3, the expression works as expected.
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Bhargava-MSFT 31,261 Reputation points Microsoft Employee Moderator
2024-07-12T16:36:25.7533333+00:00 Since the expression works with hardcoded values but not with parameters, it seems likely that the issue is related to how the parameters are being passed or interpreted within the flowlet.
Can you confirm the parameters i2 and i3 are indeed being passed as integer?
Also make sure MapDecimal are explicitly cast to integers if they are not already.
MapDecimal(sltchg, toInteger(9), toInteger(2))
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Luis Trujillo 20 Reputation points
2024-07-12T17:02:08.92+00:00 The expression is being call as:
MapDecimal(sltchg,toInteger(9),toInteger(2))
This function is defined in the Mapping_Library data flow library as:
MapDecimal(i1 as any, i2 as integer, i3 as integer) as decimal(10,0) = iif(isDecimal(i1),toDecimal(i1,toInteger(i2),toInteger(i3)), toDecimal('0.00',toInteger(i2),toInteger(i3)))
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