Made "SET key=value" returns the newly set key value pair

Author: liancheng

sql/core/src/main/scala/org/apache/spark/sql/execution/commands.scala

@@ -48,7 +48,7 @@ case class SetCommand(
     // Set value for key k.
     case (Some(k), Some(v)) =>
       context.set(k, v)
-      Array.empty[(String, String)]
+      Array(k -> v)
 
     // Query the value bound to key k.
     case (Some(k), _) =>

sql/hive/src/test/scala/org/apache/spark/sql/hive/execution/HiveQuerySuite.scala

@@ -250,10 +250,12 @@ class HiveQuerySuite extends HiveComparisonTest {
     clear()
 
     // "set" itself returns all config variables currently specified in SQLConf.
-    assert(hql("set").collect().size == 0)
+    assert(hql("SET").collect().size == 0)
+
+    assertResult(Array(testKey -> testVal)) {
+      rowsToPairs(hql(s"SET $testKey=$testVal").collect())
+    }
 
-    // "set key=val"
-    hql(s"SET $testKey=$testVal")
     assert(hiveconf.get(testKey, "") == testVal)
     assertResult(Array(testKey -> testVal)) {
       rowsToPairs(hql("SET").collect())
@@ -278,7 +280,10 @@ class HiveQuerySuite extends HiveComparisonTest {
     clear()
     assert(sql("SET").collect().size == 0)
 
-    sql(s"SET $testKey=$testVal")
+    assertResult(Array(testKey -> testVal)) {
+      rowsToPairs(sql(s"SET $testKey=$testVal").collect())
+    }
+
     assert(hiveconf.get(testKey, "") == testVal)
     assertResult(Array(testKey -> testVal)) {
       rowsToPairs(sql("SET").collect())