IMPALA-10748: Remove enable_orc_scanner flag

Impala supports reading ORC files by default for quite some time.

Removed enable_orc_scanner flag and related code and test, disabling
ORC support is no longer possible.
Removed notes on how to disable ORC support from docs.

Change-Id: I7ff640afb98cbe3aa46bf03f9bff782574c998a5
Reviewed-on: http://gerrit.cloudera.org:8080/18188
Reviewed-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
Tested-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>

be/src/common/global-flags.cc

@@ -396,6 +396,7 @@ REMOVED_FLAG(coordinator_rpc_threads);
 REMOVED_FLAG(disable_admission_control);
 REMOVED_FLAG(disable_mem_pools);
 REMOVED_FLAG(enable_accept_queue_server);
+REMOVED_FLAG(enable_orc_scanner);
 REMOVED_FLAG(enable_partitioned_aggregation);
 REMOVED_FLAG(enable_partitioned_hash_join);
 REMOVED_FLAG(enable_phj_probe_side_filtering);

be/src/exec/hdfs-orc-scanner.cc

@@ -39,9 +39,6 @@
 using namespace impala;
 using namespace impala::io;
 
-DEFINE_bool(enable_orc_scanner, true,
-    "If false, reading from ORC format tables is not supported");
-
 Status HdfsOrcScanner::IssueInitialRanges(HdfsScanNodeBase* scan_node,
     const vector<HdfsFileDesc*>& files) {
   DCHECK(!files.empty());

be/src/util/backend-gflag-util.cc

@@ -31,7 +31,6 @@
 DECLARE_bool(load_catalog_in_background);
 DECLARE_bool(load_auth_to_local_rules);
 DECLARE_bool(enable_stats_extrapolation);
-DECLARE_bool(enable_orc_scanner);
 DECLARE_bool(use_local_catalog);
 DECLARE_int32(local_catalog_cache_expiration_s);
 DECLARE_int32(local_catalog_cache_mb);
@@ -200,7 +199,6 @@ Status GetConfigFromCommand(const string& flag_cmd, string& result) {
 
 Status PopulateThriftBackendGflags(TBackendGflags& cfg) {
   cfg.__set_load_catalog_in_background(FLAGS_load_catalog_in_background);
-  cfg.__set_enable_orc_scanner(FLAGS_enable_orc_scanner);
   cfg.__set_use_local_catalog(FLAGS_use_local_catalog);
   cfg.__set_local_catalog_cache_mb(FLAGS_local_catalog_cache_mb);
   cfg.__set_local_catalog_cache_expiration_s(

common/thrift/BackendGflags.thrift

@@ -74,7 +74,7 @@ struct TBackendGflags {
 
   24: required i64 min_buffer_size
 
-  25: required bool enable_orc_scanner
+  // REMOVED: 25: required bool enable_orc_scanner
 
   26: required string authorized_proxy_group_config
 

docs/topics/impala_file_formats.xml

@@ -126,8 +126,7 @@ under the License.
               gzip, Snappy, LZO, LZ4; currently gzip by default
             </entry>
             <entry> Yes, in Impala 2.12.0 and higher. <p>By default, ORC reads are enabled in Impala
-              3.4.0 and higher. To disable, set <codeph>--enable_orc_scanner</codeph> to 
-              <codeph>false</codeph> when starting the cluster. </p>
+              3.4.0 and higher. </p>
             </entry>
             <entry>
               No. Import data by using <codeph>LOAD DATA</codeph> on data files already in the

docs/topics/impala_orc.xml

@@ -37,8 +37,7 @@ under the License.
 
     <p>
       <indexterm audience="hidden">ORC support in Impala</indexterm> Impala supports using ORC data
-      files. By default, ORC reads are enabled in Impala 3.4.0. To disable, set --enable_orc_scanner
-      to false when starting the cluster. </p>
+      files. By default, ORC reads are enabled in Impala 3.4.0 and higher.</p>
 
     <table>
       <title>ORC Format Support in Impala</title>

fe/src/main/java/org/apache/impala/planner/HdfsScanNode.java

@@ -447,22 +447,12 @@ public class HdfsScanNode extends ScanNode {
    * a partition that has a format for which we do not support complex types,
    * regardless of whether a complex-typed column is actually referenced
    * in the query.
-   * 2) if we are scanning ORC partitions and the ORC scanner is disabled.
    */
   @Override
   protected void checkForSupportedFileFormats() throws NotImplementedException {
     Preconditions.checkNotNull(desc_);
     Preconditions.checkNotNull(desc_.getTable());
 
-    if (!BackendConfig.INSTANCE.isOrcScannerEnabled()) {
-      for (FeFsPartition part: partitions_) {
-        if (part.getFileFormat() == HdfsFileFormat.ORC) {
-          throw new NotImplementedException(
-              "ORC scans are disabled by --enable_orc_scanner flag");
-        }
-      }
-    }
-
     Column firstComplexTypedCol = null;
     for (Column col: desc_.getTable().getColumns()) {
       if (col.getType().isComplexType()) {

fe/src/main/java/org/apache/impala/service/BackendConfig.java

@@ -145,10 +145,6 @@ public class BackendConfig {
 
   public boolean isInsertEventsEnabled() { return backendCfg_.enable_insert_events; }
 
-  public boolean isOrcScannerEnabled() {
-    return backendCfg_.enable_orc_scanner;
-  }
-
   /**
    * Returns the value of the `authorization_factory_class` flag or `null` if
    * the flag was not specified.

testdata/workloads/functional-query/queries/QueryTest/disable-orc-scanner.test

@@ -1,7 +0,0 @@
-====
----- QUERY
-# Test that running with ORC scanner disabled fails gracefully.
-select * from functional_orc_def.alltypes
----- CATCH
-ORC scans are disabled by --enable_orc_scanner flag
-====

tests/custom_cluster/test_disable_features.py

@@ -29,11 +29,6 @@ class TestDisableFeatures(CustomClusterTestSuite):
   def get_workload(self):
     return 'functional-query'
 
-  @pytest.mark.execute_serially
-  @CustomClusterTestSuite.with_args("--enable_orc_scanner=false")
-  def test_disable_orc_scanner(self, vector):
-    self.run_test_case('QueryTest/disable-orc-scanner', vector)
-
   @SkipIf.not_hdfs
   @pytest.mark.execute_serially
   @UniqueDatabase.parametrize(sync_ddl=True)