[doc] Add more examples of insert overwrite partition (apache#5366)

Author: Zouxxyy

docs/content/spark/sql-write.md

@@ -85,6 +85,8 @@ INSERT INTO my_table VALUES (1, 'p1'), (2, 'p2');
 
 -- Static overwrite (Overwrite the whole table)
 INSERT OVERWRITE my_table VALUES (3, 'p1');
+-- or 
+INSERT OVERWRITE my_table PARTITION (pt) VALUES (3, 'p1');
 
 SELECT * FROM my_table;
 /*
@@ -95,6 +97,19 @@ SELECT * FROM my_table;
 +---+---+
 */
 
+-- Static overwrite with specified partitions (Only overwrite pt='p1')
+INSERT OVERWRITE my_table PARTITION (pt='p1') VALUES (3);
+
+SELECT * FROM my_table;
+/*
++---+---+
+| id| pt|
++---+---+
+|  2| p2|
+|  3| p1|
++---+---+
+*/
+  
 -- Dynamic overwrite (Only overwrite pt='p1')
 SET spark.sql.sources.partitionOverwriteMode=dynamic;
 INSERT OVERWRITE my_table VALUES (3, 'p1');

paimon-spark/paimon-spark-ut/src/test/scala/org/apache/paimon/spark/sql/InsertOverwriteTableTestBase.scala

@@ -575,4 +575,37 @@ abstract class InsertOverwriteTableTestBase extends PaimonSparkTestBase {
         }
     }
   }
+
+  test("Paimon Insert: dynamic insert overwrite partition") {
+    withTable("my_table") {
+      sql("CREATE TABLE my_table (id INT, pt STRING) PARTITIONED BY (pt)")
+
+      for (mode <- Seq("static", "dynamic")) {
+        withSparkSQLConf("spark.sql.sources.partitionOverwriteMode" -> mode) {
+          sql("INSERT OVERWRITE my_table VALUES (1, 'p1'), (2, 'p2')")
+          // INSERT OVERWRITE table
+          sql("INSERT OVERWRITE my_table VALUES (3, 'p1')")
+          if (mode == "dynamic") {
+            checkAnswer(sql("SELECT * FROM my_table ORDER BY id"), Seq(Row(2, "p2"), Row(3, "p1")))
+          } else {
+            checkAnswer(sql("SELECT * FROM my_table ORDER BY id"), Row(3, "p1"))
+          }
+
+          sql("INSERT OVERWRITE my_table VALUES (1, 'p1'), (2, 'p2')")
+          // INSERT OVERWRITE table PARTITION (pt)
+          sql("INSERT OVERWRITE my_table PARTITION (pt) VALUES (3, 'p1')")
+          if (mode == "dynamic") {
+            checkAnswer(sql("SELECT * FROM my_table ORDER BY id"), Seq(Row(2, "p2"), Row(3, "p1")))
+          } else {
+            checkAnswer(sql("SELECT * FROM my_table ORDER BY id"), Row(3, "p1"))
+          }
+
+          sql("INSERT OVERWRITE my_table VALUES (1, 'p1'), (2, 'p2')")
+          // INSERT OVERWRITE table PARTITION (pt='p1')
+          sql("INSERT OVERWRITE my_table PARTITION (pt='p1') VALUES (3)")
+          checkAnswer(sql("SELECT * FROM my_table ORDER BY id"), Seq(Row(2, "p2"), Row(3, "p1")))
+        }
+      }
+    }
+  }
 }