[BUG] DELETE fails with AnalysisException on tables with CHAR(N) columns

[clee704]

Bug

Which Delta project/connector is this regarding?

• Spark
• Standalone
• Flink
• Kernel
• Other (fill in here)

Describe the problem

DELETE fails with AnalysisException on tables with CHAR(N) columns

Steps to reproduce

import io.delta.tables.DeltaTable
spark.sql("create table test (a char(5)) using delta")
DeltaTable.forName(spark, "test").delete()

Observed results

org.apache.spark.sql.delta.DeltaAnalysisException: [DELTA_UNSUPPORTED_SOURCE] DELETE destination only supports Delta sources.
Some(DeleteFromTable true
+- SubqueryAlias spark_catalog.default.test
   +- Project [staticinvoke(class org.apache.spark.sql.catalyst.util.CharVarcharCodegenUtils, StringType, readSidePadding, a#51, 5, true, false, true) AS a#52]
      +- Relation spark_catalog.default.test[a#51] parquet
)
  at org.apache.spark.sql.delta.DeltaErrorsBase.notADeltaSourceException(DeltaErrors.scala:536)
  at org.apache.spark.sql.delta.DeltaErrorsBase.notADeltaSourceException$(DeltaErrors.scala:534)
  at org.apache.spark.sql.delta.DeltaErrors$.notADeltaSourceException(DeltaErrors.scala:3382)
  at org.apache.spark.sql.delta.DeltaAnalysis$$anonfun$apply$1.applyOrElse(DeltaAnalysis.scala:465)
  at org.apache.spark.sql.delta.DeltaAnalysis$$anonfun$apply$1.applyOrElse(DeltaAnalysis.scala:81)

Expected results

DELETE is performed.

Further details

It fails because the following code returns multiple indices:

val indices = newTarget.collect {
  case DeltaFullTable(_, index) => index
}

when newTarget is a Project with a Relation as a child. The project node is added by Spark to add CharVarcharCodegenUtils.readSidePadding.

Environment information

• Delta Lake version: 3.2.1
• Spark version: 3.5.4
• Scala version: 2.12.18

Willingness to contribute

The Delta Lake Community encourages bug fix contributions. Would you or another member of your organization be willing to contribute a fix for this bug to the Delta Lake code base?

• Yes. I can contribute a fix for this bug independently.
• Yes. I would be willing to contribute a fix for this bug with guidance from the Delta Lake community.
• No. I cannot contribute a bug fix at this time.