rdblue commented on a change in pull request #24937: [SPARK-28139][SQL] Add v2 
ALTER TABLE implementation.
URL: https://github.com/apache/spark/pull/24937#discussion_r297917661
 
 

 ##########
 File path: 
sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/CheckAnalysis.scala
 ##########
 @@ -313,6 +314,42 @@ trait CheckAnalysis extends PredicateHelper {
               failAnalysis(s"Invalid partitioning: ${badReferences.mkString(", 
")}")
             }
 
+          case alter: AlterTable if alter.childrenResolved =>
+            val table = alter.table
+            def findField(operation: String, fieldName: Array[String]): 
StructField = {
+              // include collections because structs nested in maps and arrays 
may be altered
+              val field = table.schema.findNestedField(fieldName, 
includeCollections = true)
+              if (field.isEmpty) {
+                throw new AnalysisException(
+                  s"Cannot $operation missing field in ${table.name} schema: 
${fieldName.quoted}")
+              }
+              field.get
+            }
+
+            alter.changes.foreach {
+              case add: AddColumn =>
+                val parent = add.fieldNames.init
+                if (parent.nonEmpty) {
+                  findField("add to", parent)
+                }
+              case update: UpdateColumnType =>
+                val field = findField("update", update.fieldNames)
+                if (!Cast.canUpCast(field.dataType, update.newDataType)) {
 
 Review comment:
   Okay, I agree that you should not be able to alter complex types with 
another complex type

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
[email protected]


With regards,
Apache Git Services

---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to