[Spark] Execute MERGE using Dataframe API in Scala (#3456)

## Description
Due to Spark unfortunate behavior of resolving plan nodes it doesn't
know, the `DeltaMergeInto` plan created when using the MERGE scala API
needs to be manually resolved to ensure spark doesn't interfere with its
analysis.

This currently completely bypasses Spark's analysis as we then manually
execute the MERGE command which has negatiev effects, e.g. the execution
is not visible in QueryExecutionListener.

This change addresses this issue, by executing the plan using the
Dataframe API after it's manually resolved so that the command goes
through the regular code path.

Resolves #1521
## How was this patch tested?
Covered by existing tests.

Author: johanl-db

spark/src/main/scala/io/delta/tables/DeltaMergeBuilder.scala

@@ -323,7 +323,7 @@ class DeltaMergeBuilder private(
       // Resolve UpCast expressions that `PreprocessTableMerge` may have introduced.
       mergeIntoCommand = PostHocResolveUpCast(sparkSession).apply(mergeIntoCommand)
       sparkSession.sessionState.analyzer.checkAnalysis(mergeIntoCommand)
-      mergeIntoCommand.asInstanceOf[MergeIntoCommand].run(sparkSession)
+      toDataset(sparkSession, mergeIntoCommand)
     }
   }
 

spark/src/test/scala/org/apache/spark/sql/delta/MergeIntoSuiteBase.scala

@@ -23,6 +23,7 @@ import java.util.Locale
 import scala.language.implicitConversions
 
 import com.databricks.spark.util.{Log4jUsageLogger, MetricDefinitions, UsageRecord}
+import org.apache.spark.sql.delta.commands.MergeIntoCommand
 import org.apache.spark.sql.delta.commands.merge.MergeStats
 import org.apache.spark.sql.delta.sources.DeltaSQLConf
 import org.apache.spark.sql.delta.test.DeltaSQLTestUtils
@@ -3362,6 +3363,25 @@ abstract class MergeIntoSuiteBase
     "delta.dml.merge.findTouchedFiles",
     "delta.dml.merge.writeInsertsOnlyWhenNoMatches",
     "delta.dml.merge")
+
+  test("merge execution is recorded with QueryExecutionListener") {
+    withKeyValueData(
+      source = (0, 0) :: (1, 10) :: Nil,
+      target = (1, 1) :: (2, 2) :: Nil) { case (sourceName, targetName) =>
+      val plans = withLogicalPlansCaptured(spark, optimizedPlan = false) {
+        executeMerge(
+          tgt = s"$targetName t",
+          src = s"$sourceName s",
+          cond = "s.key = t.key",
+          update(set = "*"))
+      }
+      val mergeCommands = plans.collect {
+        case m: MergeIntoCommand => m
+      }
+      assert(mergeCommands.size === 1,
+        "Merge command wasn't properly recorded by QueryExecutionListener")
+    }
+  }
 }
 
 

spark/src/test/scala/org/apache/spark/sql/delta/SchemaValidationSuite.scala

@@ -26,21 +26,15 @@ import org.apache.spark.sql.catalyst.rules.Rule
 import org.apache.spark.sql.functions._
 import org.apache.spark.sql.test.SharedSparkSession
 
-trait SchemaValidationSuiteBase extends QueryTest with SharedSparkSession with DeltaSQLCommandTest {
-
-  def checkMergeException(e: Exception, col: String): Unit = {
-    assert(e.isInstanceOf[MetadataChangedException])
-    assert(e.getMessage.contains(
-      "The metadata of the Delta table has been changed by a concurrent update"))
-  }
-}
-
 /**
  * This Suite tests the behavior of Delta commands when a schema altering commit is run after the
  * command completes analysis but before the command starts the transaction. We want to make sure
  * That we do not corrupt tables.
  */
-class SchemaValidationSuite extends SchemaValidationSuiteBase {
+class SchemaValidationSuite
+  extends QueryTest
+  with SharedSparkSession
+  with DeltaSQLCommandTest {
 
   class BlockingRule(
       blockActionLatch: CountDownLatch,
@@ -331,7 +325,7 @@ class SchemaValidationSuite extends SchemaValidationSuiteBase {
 
   /**
    * Concurrently drop column in merge condition. Merge command detects the schema change while
-   * resolving the target and throws an AnalysisException
+   * resolving the target and throws a DeltaAnalysisException
    */
   testConcurrentChange("merge - remove a column in merge condition concurrently")(
     createTable = (spark: SparkSession, tblPath: String) => {
@@ -343,7 +337,7 @@ class SchemaValidationSuite extends SchemaValidationSuiteBase {
     actionToTest = (spark: SparkSession, tblPath: String) => {
       val deltaTable = io.delta.tables.DeltaTable.forPath(spark, tblPath)
       val sourceDf = spark.range(10).withColumn("col2", lit(2))
-      val e = intercept[Exception] {
+      val e = intercept[DeltaAnalysisException] {
         deltaTable.as("t1")
           .merge(sourceDf.as("t2"), "t1.id == t2.id")
           .whenNotMatched()
@@ -352,14 +346,22 @@ class SchemaValidationSuite extends SchemaValidationSuiteBase {
           .updateAll()
           .execute()
       }
-      checkMergeException(e, "id")
+
+      checkErrorMatchPVals(
+        exception = e,
+        errorClass = "DELTA_SCHEMA_CHANGE_SINCE_ANALYSIS",
+        parameters = Map(
+          "schemaDiff" -> ".*id.*",
+          "legacyFlagMessage" -> ""
+        )
+      )
     },
     concurrentChange = dropColFromSampleTable("id")
   )
 
   /**
    * Concurrently drop column not in merge condition but in target. Merge command detects the schema
-   * change while resolving the target and throws an AnalysisException
+   * change while resolving the target and throws a DeltaAnalysisException
    */
   testConcurrentChange("merge - remove a column not in merge condition concurrently")(
     createTable = (spark: SparkSession, tblPath: String) => {
@@ -371,7 +373,7 @@ class SchemaValidationSuite extends SchemaValidationSuiteBase {
     actionToTest = (spark: SparkSession, tblPath: String) => {
       val deltaTable = io.delta.tables.DeltaTable.forPath(spark, tblPath)
       val sourceDf = spark.range(10).withColumn("col2", lit(2))
-      val e = intercept[Exception] {
+      val e = intercept[DeltaAnalysisException] {
         deltaTable.as("t1")
           .merge(sourceDf.as("t2"), "t1.id == t2.id")
           .whenNotMatched()
@@ -380,7 +382,14 @@ class SchemaValidationSuite extends SchemaValidationSuiteBase {
           .updateAll()
           .execute()
       }
-      checkMergeException(e, "col2")
+      checkErrorMatchPVals(
+        exception = e,
+        errorClass = "DELTA_SCHEMA_CHANGE_SINCE_ANALYSIS",
+        parameters = Map(
+          "schemaDiff" -> ".*col2.*",
+          "legacyFlagMessage" -> ""
+        )
+      )
     },
     concurrentChange = dropColFromSampleTable("col2")
   )