[Fix](statistics)Fix analyze olap table couldn't get partition names bug.

fe/fe-core/src/main/java/org/apache/doris/analysis/AnalyzeTblStmt.java

@@ -24,6 +24,7 @@
 import org.apache.doris.catalog.OlapTable;
 import org.apache.doris.catalog.TableIf;
 import org.apache.doris.catalog.View;
+import org.apache.doris.catalog.external.ExternalTable;
 import org.apache.doris.catalog.external.HMSExternalTable;
 import org.apache.doris.common.AnalysisException;
 import org.apache.doris.common.Config;
@@ -41,6 +42,7 @@
 import com.google.common.collect.Sets;
 import org.apache.commons.lang3.StringUtils;
 
+import java.util.Collections;
 import java.util.List;
 import java.util.Optional;
 import java.util.Set;
@@ -239,16 +241,15 @@ public Set<String> getColumnNames() {
 
     public Set<String> getPartitionNames() {
         if (partitionNames == null || partitionNames.getPartitionNames() == null) {
-            return null;
+            if (table instanceof ExternalTable) {
+                // External table couldn't return all partitions when partitionNames is not set.
+                // Because Analyze Table command for external table could specify partition names.
+                return Collections.emptySet();
+            }
+            return table.getPartitionNames();
         }
         Set<String> partitions = Sets.newHashSet();
         partitions.addAll(partitionNames.getPartitionNames());
-        /*
-            if (isSamplingPartition()) {
-                int partNum = ConnectContext.get().getSessionVariable().getExternalTableAnalyzePartNum();
-                partitions = partitions.stream().limit(partNum).collect(Collectors.toSet());
-            }
-        */
         return partitions;
     }
 

regression-test/suites/statistics/test_basic_statistics.groovy

@@ -0,0 +1,75 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+suite("test_basic_statistics") {
+    String db = "test_basic_statistics"
+    String tbl = "test_table_1"
+
+    sql """
+        DROP DATABASE IF EXISTS `${db}`
+    """
+
+    sql """
+        CREATE DATABASE `${db}`
+    """
+
+    sql """ use `${db}`"""
+
+    sql """
+        DROP TABLE IF EXISTS `${tbl}`
+    """
+
+    sql """
+          CREATE TABLE IF NOT EXISTS `${tbl}` (
+            `id` int(11) not null comment "",
+            `name` varchar(100) null comment ""
+        ) engine=olap
+        DUPLICATE KEY(`id`)
+        DISTRIBUTED BY HASH(`id`) BUCKETS 1 properties("replication_num" = "1")
+    """
+
+    sql """
+        INSERT INTO `${tbl}` VALUES (1, 'name1'), (2, 'name2'), (3, 'name3'), (4, 'name4'), (5, 'name5'), (6, 'name6'), (7, 'name7'), (8, 'name8'), (9, 'name9')
+    """
+
+    sql """ analyze table ${tbl} with sync"""
+    def result = sql """show column stats ${tbl} (id)"""
+    assertTrue(result.size() == 1)
+    assertTrue(result[0][0] == "id")
+    assertTrue(result[0][1] == "9.0")
+    assertTrue(result[0][2] == "9.0")
+    assertTrue(result[0][3] == "0.0")
+    assertTrue(result[0][4] == "40.0")
+    assertTrue(result[0][5] == "4.0")
+    assertTrue(result[0][6] == "1")
+    assertTrue(result[0][7] == "9")
+
+    result = sql """show column stats ${tbl} (name)"""
+    assertTrue(result.size() == 1)
+    assertTrue(result[0][0] == "name")
+    assertTrue(result[0][1] == "9.0")
+    assertTrue(result[0][2] == "9.0")
+    assertTrue(result[0][3] == "0.0")
+    assertTrue(result[0][4] == "50.0")
+    assertTrue(result[0][5] == "5.0")
+    assertTrue(result[0][6] == "\'name1\'")
+    assertTrue(result[0][7] == "\'name9\'")
+
+    sql """drop table ${tbl}"""
+    sql """drop database ${db}"""
+
+}