Hi,
I've this JSON document :
{ "b": [ { "e": 1 } ] }
When I do :
df.select(expr("transform( b, v1 -> struct(v1.e) )"))
I get this error :
cannot resolve 'named_struct(NamePlaceholder(), namedlambdavariable().e)'
due to data type mismatch: Only foldable string expressions are allowed to
appear at odd position, got: NamePlaceholder; line 1 pos 20; 'Project
[unresolvedalias(transform(b#5,
lambdafunction(named_struct(NamePlaceholder, lambda v1#7.e), lambda v1#7,
false)), Some(<function1>))] +- LogicalRDD [b#5], false
org.apache.spark.sql.AnalysisException: cannot resolve
'named_struct(NamePlaceholder(), namedlambdavariable().`e`)' due to
data type mismatch: Only foldable string expressions are allowed to
appear at odd position, got: NamePlaceholder; line 1 pos 20;
'Project [unresolvedalias(transform(b#5,
lambdafunction(named_struct(NamePlaceholder, lambda v1#7.e), lambda
v1#7, false)), Some(<function1>))]
+- LogicalRDD [b#5], false
at
org.apache.spark.sql.catalyst.analysis.package$AnalysisErrorAt.failAnalysis(package.scala:42)
at
org.apache.spark.sql.catalyst.analysis.CheckAnalysis$$anonfun$checkAnalysis$1$$anonfun$apply$3.applyOrElse(CheckAnalysis.scala:115)
at
org.apache.spark.sql.catalyst.analysis.CheckAnalysis$$anonfun$checkAnalysis$1$$anonfun$apply$3.applyOrElse(CheckAnalysis.scala:107)
at
org.apache.spark.sql.catalyst.trees.TreeNode$$anonfun$transformUp$1.apply(TreeNode.scala:278)
at
org.apache.spark.sql.catalyst.trees.TreeNode$$anonfun$transformUp$1.apply(TreeNode.scala:278)
at
org.apache.spark.sql.catalyst.trees.CurrentOrigin$.withOrigin(TreeNode.scala:70)
at
org.apache.spark.sql.catalyst.trees.TreeNode.transformUp(TreeNode.scala:277)
...
By doing some investigations, it seems that this error is due to the
fact that v1.e is seen as a NamePlaceHolder and not as a Literal. This
is somewhat understandable, as v1 is not resolved here. But, isn't it
possible that struct(v1.e) uses v1.e as a field name?
regards,
françois-
