[ 
https://issues.apache.org/jira/browse/HIVE-26498?focusedWorklogId=807407&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-807407
 ]

ASF GitHub Bot logged work on HIVE-26498:
-----------------------------------------

                Author: ASF GitHub Bot
            Created on: 09/Sep/22 13:21
            Start Date: 09/Sep/22 13:21
    Worklog Time Spent: 10m 
      Work Description: lcspinter commented on code in PR #3552:
URL: https://github.com/apache/hive/pull/3552#discussion_r967065389


##########
ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/views/HiveMaterializedViewUtils.java:
##########
@@ -160,11 +181,79 @@ public static Boolean isOutdatedMaterializedView(
     return false;
   }
 
+  private static Boolean isOutdatedMaterializedView(
+          MaterializationSnapshot snapshot, Hive db,
+          Set<TableName> tablesUsed, Table materializedViewTable) throws 
HiveException {
+    List<String> tablesUsedNames = tablesUsed.stream()
+        .map(tableName -> TableName.getDbTable(tableName.getDb(), 
tableName.getTable()))
+        .collect(Collectors.toList());
+
+    Map<String, String> snapshotMap = snapshot.getTableSnapshots();
+    if (snapshotMap == null || snapshotMap.isEmpty()) {
+      LOG.debug("Materialized view " + 
materializedViewTable.getFullyQualifiedName() +
+              " ignored for rewriting as we could not obtain current snapshot 
ids");
+      return null;
+    }
+
+    Set<String> storedTablesUsed = 
materializedViewTable.getMVMetadata().getSourceTableFullNames();
+    for (String fullyQualifiedTableName : tablesUsedNames) {
+      // Note. If the materialized view does not contain a table that is 
contained in the query,
+      // we do not need to check whether that specific table is outdated or 
not. If a rewriting
+      // is produced in those cases, it is because that additional table is 
joined with the
+      // existing tables with an append-columns only join, i.e., PK-FK + not 
null.
+      if (!storedTablesUsed.contains(fullyQualifiedTableName)) {
+        continue;
+      }
+
+      Table table = db.getTable(fullyQualifiedTableName);
+      if (table.getStorageHandler() == null) {
+        LOG.debug("Materialized view {} ignored for rewriting as we could not 
storage handler of table {}",
+                materializedViewTable.getFullyQualifiedName(), 
fullyQualifiedTableName);
+        return null;
+      }
+      String currentTableSnapshot = 
table.getStorageHandler().getCurrentSnapshotId(table);
+      if (isBlank(currentTableSnapshot)) {

Review Comment:
   Thanks! I really like this new change





Issue Time Tracking
-------------------

    Worklog Id:     (was: 807407)
    Time Spent: 5h 10m  (was: 5h)

> Implement MV maintenance with Iceberg sources using full rebuild
> ----------------------------------------------------------------
>
>                 Key: HIVE-26498
>                 URL: https://issues.apache.org/jira/browse/HIVE-26498
>             Project: Hive
>          Issue Type: Sub-task
>          Components: Materialized views
>            Reporter: Krisztian Kasa
>            Assignee: Krisztian Kasa
>            Priority: Major
>              Labels: pull-request-available
>          Time Spent: 5h 10m
>  Remaining Estimate: 0h
>
> {code}
> set hive.support.concurrency=true;
> set hive.txn.manager=org.apache.hadoop.hive.ql.lockmgr.DbTxnManager;
> create external table tbl_ice(a int, b string, c int) stored by iceberg 
> stored as orc tblproperties ('format-version'='2');
> insert into tbl_ice values (1, 'one', 50), (2, 'two', 51), (3, 'three', 52), 
> (4, 'four', 53), (5, 'five', 54);
> create materialized view mat1 as
> select b, c from tbl_ice where c > 52;
> insert into tbl_ice values (111, 'one', 55), (333, 'two', 56);
> explain cbo
> alter materialized view mat1 rebuild;
> alter materialized view mat1 rebuild;
> {code}
> MV full rebuild plan
> {code}
> CBO PLAN:
> HiveProject(b=[$1], c=[$2])
>   HiveFilter(condition=[>($2, 52)])
>     HiveTableScan(table=[[default, tbl_ice]], table:alias=[tbl_ice])
> {code}



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