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Comment: Published by Scroll Versions from space DEV and version next

D toc

 

Excerpt

Function returns the first non-missing value found in an array of columns.

The order of the columns listed in the function determines the order in which they are searched.

D s-lang-vs-sql

D s
snippetBasic

COALESCE
d-code-lang-syntax
RawWrangletrue
Typeref
showNotetrue
WrangleTextderive type:single value:
coalesce([col1,col2,col3]) as: 'firstValue'

coalesce([col1,col2,col3])

Output: Generates the firsValue column, which contains the Returns the first non-missing detected in col1,  col2, or or col3 in that order. 

D s
snippetSyntax

COALESCE
d-codelang-syntax
RawWrangletrue
Typesyntax
showNotetrue
WrangleTextderive type:single value:
coalesce([col_ref1,col_ref2, col_ref3])

coalesce([col_ref1,col_ref2, col_ref3])

A reference to a single column does not require brackets. References to multiple columns must be passed to the function as an array of column names.

ArgumentRequired?Data TypeDescription
col_ref1YstringName of the first column to find the first non-missing value
col_ref2NstringName of the second column to find the first non-missing value
col_ref3NstringName of the third column to find the first non-missing value

D s lang notes

col_ref1, col_ref2, col_ref3

...

You are tracking multiple racers across multiple heats. Racers might sit out heats for various reasons. 

Source:

Here's the race data.

RacerHeat1Heat2Heat3
Racer X 38.2237.61
Racer Y41.33 38.04
Racer Z39.2739.0438.85

TransformTransformation:

Use the following transform to grab the first non-missing value from the Heat columns:

d-

...

trans
RawWrangletrue
p03Value'firstTime'
Typestep
WrangleTextderive type:single value:

...

coalesce([Heat1, Heat2, Heat3]) as:'firstTime'
p01NameFormula type
p01ValueSingle row formula
p02NameFormula
p02Valuecoalesce([Heat1, Heat2, Heat3])
p03NameNew column name
SearchTermNew formula

Results:

RacerHeat1Heat2Heat3firstTime
Racer X 38.2237.6138.22
Racer Y41.33 38.0441.33
Racer Z39.2739.0438.8539.27

D s also
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