Examples with MaterializedViewHandlerInfo org.voltdb.catalog.MaterializedViewHandlerInfo used on opensource projects

Example 1 with MaterializedViewHandlerInfo

use of org.voltdb.catalog.MaterializedViewHandlerInfo in project voltdb by VoltDB.

the class SwapTablesPlanNode method viewsDependOn.

/**
     * @param theTable
     * @return
     */
private static boolean viewsDependOn(Table aTable, StringBuilder viewNames) {
    String separator = "(";
    for (MaterializedViewInfo anyView : aTable.getViews()) {
        viewNames.append(separator).append(anyView.getTypeName());
        separator = ", ";
    }
    for (Table anyTable : ((Database) aTable.getParent()).getTables()) {
        for (MaterializedViewHandlerInfo anyView : anyTable.getMvhandlerinfo()) {
            if (anyView.getSourcetables().getIgnoreCase(aTable.getTypeName()) != null) {
                viewNames.append(separator).append(anyView.getDesttable().getTypeName());
                separator = ", ";
            }
        }
    }
    if (", ".equals(separator)) {
        viewNames.append(")");
        return true;
    }
    return false;
}

Example 2 with MaterializedViewHandlerInfo

use of org.voltdb.catalog.MaterializedViewHandlerInfo in project voltdb by VoltDB.

the class MaterializedViewFixInfo method processMVBasedQueryFix.

/**
     * Check whether the results from a materialized view need to be
     * re-aggregated on the coordinator by the view's GROUP BY columns
     * prior to any of the processing specified by the query.
     * This is normally the case when a mat view's source table is partitioned
     * and the view's GROUP BY does not include the partition key.
     * There is a special edge case where the query already contains the exact
     * reaggregations that the added-cost fix would introduce, so the fix can
     * be skipped as an optimization.
     * Set the m_needed flag to true, only if the reaggregation fix is needed.
     * @return The value of m_needed
     */
public boolean processMVBasedQueryFix(StmtTableScan mvTableScan, Set<SchemaColumn> scanColumns, JoinNode joinTree, List<ParsedColInfo> displayColumns, List<ParsedColInfo> groupByColumns) {
    //@TODO
    if (!(mvTableScan instanceof StmtTargetTableScan)) {
        return false;
    }
    Table table = ((StmtTargetTableScan) mvTableScan).getTargetTable();
    assert (table != null);
    String mvTableName = table.getTypeName();
    Table srcTable = table.getMaterializer();
    if (srcTable == null) {
        return false;
    }
    if (table.getIsreplicated()) {
        return false;
    }
    // Justify whether partition column is in group by column list or not
    if (table.getPartitioncolumn() != null) {
        return false;
    }
    m_mvTableScan = mvTableScan;
    Set<String> mvDDLGroupbyColumnNames = new HashSet<>();
    List<Column> mvColumnArray = CatalogUtil.getSortedCatalogItems(table.getColumns(), "index");
    String mvTableAlias = getMVTableAlias();
    // Get the number of group-by columns.
    int numOfGroupByColumns;
    MaterializedViewInfo mvInfo = srcTable.getViews().get(mvTableName);
    if (mvInfo != null) {
        // single table view
        String complexGroupbyJson = mvInfo.getGroupbyexpressionsjson();
        if (complexGroupbyJson.length() > 0) {
            List<AbstractExpression> mvComplexGroupbyCols = null;
            try {
                mvComplexGroupbyCols = AbstractExpression.fromJSONArrayString(complexGroupbyJson, null);
            } catch (JSONException e) {
                e.printStackTrace();
            }
            numOfGroupByColumns = mvComplexGroupbyCols.size();
        } else {
            numOfGroupByColumns = mvInfo.getGroupbycols().size();
        }
    } else {
        // joined table view
        MaterializedViewHandlerInfo mvHandlerInfo = table.getMvhandlerinfo().get("mvHandlerInfo");
        numOfGroupByColumns = mvHandlerInfo.getGroupbycolumncount();
    }
    if (scanColumns.isEmpty() && numOfGroupByColumns == 0) {
        // This is an edge case that can happen if the view
        // has no group by keys, and we are just
        // doing a count(*) on the output of the view.
        //
        // Having no GB keys or scan columns would cause us to
        // produce plan nodes that have a 0-column output schema.
        // We can't handle this in several places, so add the
        // count(*) column from the view to the scan columns.
        // this is the "count(*)" column.
        Column mvCol = mvColumnArray.get(0);
        TupleValueExpression tve = new TupleValueExpression(mvTableName, mvTableAlias, mvCol, 0);
        tve.setOrigStmtId(mvTableScan.getStatementId());
        String colName = mvCol.getName();
        SchemaColumn scol = new SchemaColumn(mvTableName, mvTableAlias, colName, colName, tve);
        scanColumns.add(scol);
    }
    // Start to do real materialized view processing to fix the duplicates problem.
    // (1) construct new projection columns for scan plan node.
    Set<SchemaColumn> mvDDLGroupbyColumns = new HashSet<>();
    NodeSchema inlineProjSchema = new NodeSchema();
    for (SchemaColumn scol : scanColumns) {
        inlineProjSchema.addColumn(scol);
    }
    for (int i = 0; i < numOfGroupByColumns; i++) {
        Column mvCol = mvColumnArray.get(i);
        String colName = mvCol.getName();
        TupleValueExpression tve = new TupleValueExpression(mvTableName, mvTableAlias, mvCol, i);
        tve.setOrigStmtId(mvTableScan.getStatementId());
        mvDDLGroupbyColumnNames.add(colName);
        SchemaColumn scol = new SchemaColumn(mvTableName, mvTableAlias, colName, colName, tve);
        mvDDLGroupbyColumns.add(scol);
        if (!scanColumns.contains(scol)) {
            scanColumns.add(scol);
            // construct new projection columns for scan plan node.
            inlineProjSchema.addColumn(scol);
        }
    }
    // Record the re-aggregation type for each scan columns.
    Map<String, ExpressionType> mvColumnReAggType = new HashMap<>();
    for (int i = numOfGroupByColumns; i < mvColumnArray.size(); i++) {
        Column mvCol = mvColumnArray.get(i);
        ExpressionType reAggType = ExpressionType.get(mvCol.getAggregatetype());
        if (reAggType == ExpressionType.AGGREGATE_COUNT_STAR || reAggType == ExpressionType.AGGREGATE_COUNT) {
            reAggType = ExpressionType.AGGREGATE_SUM;
        }
        mvColumnReAggType.put(mvCol.getName(), reAggType);
    }
    assert (inlineProjSchema.size() > 0);
    m_scanInlinedProjectionNode = new ProjectionPlanNode(inlineProjSchema);
    // (2) Construct the reAggregation Node.
    // Construct the reAggregation plan node's aggSchema
    m_reAggNode = new HashAggregatePlanNode();
    int outputColumnIndex = 0;
    // inlineProjSchema contains the group by columns, while aggSchema may do not.
    NodeSchema aggSchema = new NodeSchema();
    // Construct reAggregation node's aggregation and group by list.
    for (SchemaColumn scol : inlineProjSchema.getColumns()) {
        if (mvDDLGroupbyColumns.contains(scol)) {
            // Add group by expression.
            m_reAggNode.addGroupByExpression(scol.getExpression());
        } else {
            ExpressionType reAggType = mvColumnReAggType.get(scol.getColumnName());
            assert (reAggType != null);
            AbstractExpression agg_input_expr = scol.getExpression();
            assert (agg_input_expr instanceof TupleValueExpression);
            // Add aggregation information.
            m_reAggNode.addAggregate(reAggType, false, outputColumnIndex, agg_input_expr);
        }
        aggSchema.addColumn(scol);
        outputColumnIndex++;
    }
    assert (aggSchema.size() > 0);
    m_reAggNode.setOutputSchema(aggSchema);
    // Collect all TVEs that need to be do re-aggregation in coordinator.
    List<TupleValueExpression> needReAggTVEs = new ArrayList<>();
    List<AbstractExpression> aggPostExprs = new ArrayList<>();
    for (int i = numOfGroupByColumns; i < mvColumnArray.size(); i++) {
        Column mvCol = mvColumnArray.get(i);
        TupleValueExpression tve = new TupleValueExpression(mvTableName, mvTableAlias, mvCol, -1);
        tve.setOrigStmtId(mvTableScan.getStatementId());
        needReAggTVEs.add(tve);
    }
    collectReAggNodePostExpressions(joinTree, needReAggTVEs, aggPostExprs);
    AbstractExpression aggPostExpr = ExpressionUtil.combinePredicates(aggPostExprs);
    // Add post filters for the reAggregation node.
    m_reAggNode.setPostPredicate(aggPostExpr);
    // ENG-5386
    if (m_edgeCaseQueryNoFixNeeded && edgeCaseQueryNoFixNeeded(mvDDLGroupbyColumnNames, mvColumnReAggType, displayColumns, groupByColumns)) {
        return false;
    }
    m_needed = true;
    return true;
}

Example 3 with MaterializedViewHandlerInfo

use of org.voltdb.catalog.MaterializedViewHandlerInfo in project voltdb by VoltDB.

the class ViewExplainer method explain.

public static ArrayList<String[]> explain(Table viewTable) throws Exception {
    String viewName = viewTable.getTypeName();
    MaterializedViewHandlerInfo mvHandlerInfo = viewTable.getMvhandlerinfo().get("mvHandlerInfo");
    MaterializedViewInfo mvInfo = null;
    CatalogMap<Statement> fallBackQueryStmts;
    List<Column> destColumnArray = CatalogUtil.getSortedCatalogItems(viewTable.getColumns(), "index");
    ArrayList<String[]> retval = new ArrayList<String[]>();
    // Is this view single-table?
    if (mvHandlerInfo == null) {
        // (Legacy code for single table view uses a different model and code path)
        if (viewTable.getMaterializer() == null) {
            // If we cannot find view metadata from both locations, this table is not a materialized view.
            throw new Exception("Table " + viewName + " is not a view.");
        }
        mvInfo = viewTable.getMaterializer().getViews().get(viewName);
        fallBackQueryStmts = mvInfo.getFallbackquerystmts();
    } else {
        // For multi-table views we need to show the query plan for evaluating joins.
        Statement createQuery = mvHandlerInfo.getCreatequery().get("createQuery");
        retval.add(new String[] { "Join Evaluation", Encoder.hexDecodeToString(createQuery.getExplainplan()) });
        fallBackQueryStmts = mvHandlerInfo.getFallbackquerystmts();
    }
    // For each min/max column find out if an execution plan is used.
    int minMaxAggIdx = 0;
    for (int j = 0; j < destColumnArray.size(); j++) {
        Column destColumn = destColumnArray.get(j);
        ExpressionType aggType = ExpressionType.get(destColumn.getAggregatetype());
        if (aggType == ExpressionType.AGGREGATE_MIN || aggType == ExpressionType.AGGREGATE_MAX) {
            Statement fallBackQueryStmt = fallBackQueryStmts.get(String.valueOf(minMaxAggIdx));
            // How this min/max will be refreshed?
            String plan = "";
            //   * execution plan
            if (mvHandlerInfo == null) {
                CatalogMap<IndexRef> hardCodedIndicesForSingleTableView = mvInfo.getIndexforminmax();
                String hardCodedIndexName = hardCodedIndicesForSingleTableView.get(String.valueOf(minMaxAggIdx)).getName();
                String indexNameUsedInStatement = getIndexNameUsedInStatement(fallBackQueryStmt);
                if (!indexNameUsedInStatement.equalsIgnoreCase(hardCodedIndexName)) {
                    plan = Encoder.hexDecodeToString(fallBackQueryStmt.getExplainplan());
                }
                // If we do not use execution plan, see which built-in method is used.
                if (plan.equals("")) {
                    if (hardCodedIndexName.equals("")) {
                        plan = "Built-in sequential scan.";
                    } else {
                        plan = "Built-in index scan \"" + hardCodedIndexName + "\".";
                    }
                }
            } else {
                plan = Encoder.hexDecodeToString(fallBackQueryStmt.getExplainplan());
            }
            retval.add(new String[] { "Refresh " + (aggType == ExpressionType.AGGREGATE_MIN ? "MIN" : "MAX") + " column \"" + destColumn.getName() + "\"", plan });
            minMaxAggIdx++;
        }
    }
    return retval;
}

Example 4 with MaterializedViewHandlerInfo

use of org.voltdb.catalog.MaterializedViewHandlerInfo in project voltdb by VoltDB.

the class MaterializedViewProcessor method startProcessing.

/**
     * Add materialized view info to the catalog for the tables that are
     * materialized views.
     * @throws VoltCompilerException
     */
public void startProcessing(Database db, HashMap<Table, String> matViewMap, TreeSet<String> exportTableNames) throws VoltCompilerException {
    HashSet<String> viewTableNames = new HashSet<>();
    for (Entry<Table, String> entry : matViewMap.entrySet()) {
        viewTableNames.add(entry.getKey().getTypeName());
    }
    for (Entry<Table, String> entry : matViewMap.entrySet()) {
        Table destTable = entry.getKey();
        String query = entry.getValue();
        // get the xml for the query
        VoltXMLElement xmlquery = null;
        try {
            xmlquery = m_hsql.getXMLCompiledStatement(query);
        } catch (HSQLParseException e) {
            e.printStackTrace();
        }
        assert (xmlquery != null);
        // parse the xml like any other sql statement
        ParsedSelectStmt stmt = null;
        try {
            stmt = (ParsedSelectStmt) AbstractParsedStmt.parse(query, xmlquery, null, db, null);
        } catch (Exception e) {
            throw m_compiler.new VoltCompilerException(e.getMessage());
        }
        assert (stmt != null);
        String viewName = destTable.getTypeName();
        // throw an error if the view isn't within voltdb's limited world view
        checkViewMeetsSpec(viewName, stmt);
        // The primary key index is yet to be defined (below).
        for (Index destIndex : destTable.getIndexes()) {
            if (destIndex.getUnique() || destIndex.getAssumeunique()) {
                String msg = "A UNIQUE or ASSUMEUNIQUE index is not allowed on a materialized view. " + "Remove the qualifier from the index " + destIndex.getTypeName() + "defined on the materialized view \"" + viewName + "\".";
                throw m_compiler.new VoltCompilerException(msg);
            }
        }
        // A Materialized view cannot depend on another view.
        for (Table srcTable : stmt.m_tableList) {
            if (viewTableNames.contains(srcTable.getTypeName())) {
                String msg = String.format("A materialized view (%s) can not be defined on another view (%s).", viewName, srcTable.getTypeName());
                throw m_compiler.new VoltCompilerException(msg);
            }
        }
        // The existing code base still need this materializer field to tell if a table
        // is a materialized view table. Leaving this for future refactoring.
        destTable.setMaterializer(stmt.m_tableList.get(0));
        List<Column> destColumnArray = CatalogUtil.getSortedCatalogItems(destTable.getColumns(), "index");
        List<AbstractExpression> groupbyExprs = null;
        if (stmt.hasComplexGroupby()) {
            groupbyExprs = new ArrayList<>();
            for (ParsedColInfo col : stmt.groupByColumns()) {
                groupbyExprs.add(col.expression);
            }
        }
        // Generate query XMLs for min/max recalculation (ENG-8641)
        boolean isMultiTableView = stmt.m_tableList.size() > 1;
        MatViewFallbackQueryXMLGenerator xmlGen = new MatViewFallbackQueryXMLGenerator(xmlquery, stmt.groupByColumns(), stmt.m_displayColumns, isMultiTableView);
        List<VoltXMLElement> fallbackQueryXMLs = xmlGen.getFallbackQueryXMLs();
        // index or constraint in order to avoid error and crash.
        if (stmt.groupByColumns().size() != 0) {
            Index pkIndex = destTable.getIndexes().add(HSQLInterface.AUTO_GEN_MATVIEW_IDX);
            pkIndex.setType(IndexType.BALANCED_TREE.getValue());
            pkIndex.setUnique(true);
            // assume index 1 throuh #grpByCols + 1 are the cols
            for (int i = 0; i < stmt.groupByColumns().size(); i++) {
                ColumnRef c = pkIndex.getColumns().add(String.valueOf(i));
                c.setColumn(destColumnArray.get(i));
                c.setIndex(i);
            }
            Constraint pkConstraint = destTable.getConstraints().add(HSQLInterface.AUTO_GEN_MATVIEW_CONST);
            pkConstraint.setType(ConstraintType.PRIMARY_KEY.getValue());
            pkConstraint.setIndex(pkIndex);
        }
        // If we have an unsafe MV message, then
        // remember it here.  We don't really know how
        // to transfer the message through the catalog, but
        // we can transmit the existence of the message.
        boolean isSafeForDDL = (stmt.getUnsafeMVMessage() == null);
        // Here the code path diverges for different kinds of views (single table view and joined table view)
        if (isMultiTableView) {
            // Materialized view on joined tables
            // Add mvHandlerInfo to the destTable:
            MaterializedViewHandlerInfo mvHandlerInfo = destTable.getMvhandlerinfo().add("mvHandlerInfo");
            mvHandlerInfo.setDesttable(destTable);
            for (Table srcTable : stmt.m_tableList) {
                // Now we do not support having a view on persistent tables joining streamed tables.
                if (exportTableNames.contains(srcTable.getTypeName())) {
                    String msg = String.format("A materialized view (%s) on joined tables cannot have streamed table (%s) as its source.", viewName, srcTable.getTypeName());
                    throw m_compiler.new VoltCompilerException(msg);
                }
                // The view table will need to keep a list of its source tables.
                // The list is used to install / uninstall the view reference on the source tables when the
                // view handler is constructed / destroyed.
                TableRef tableRef = mvHandlerInfo.getSourcetables().add(srcTable.getTypeName());
                tableRef.setTable(srcTable);
                // There could be more than one partition column candidate, but we will only use the first one we found.
                if (destTable.getPartitioncolumn() == null && srcTable.getPartitioncolumn() != null) {
                    Column partitionColumn = srcTable.getPartitioncolumn();
                    String partitionColName = partitionColumn.getTypeName();
                    String srcTableName = srcTable.getTypeName();
                    destTable.setIsreplicated(false);
                    if (stmt.hasComplexGroupby()) {
                        for (int i = 0; i < groupbyExprs.size(); i++) {
                            AbstractExpression groupbyExpr = groupbyExprs.get(i);
                            if (groupbyExpr instanceof TupleValueExpression) {
                                TupleValueExpression tve = (TupleValueExpression) groupbyExpr;
                                if (tve.getTableName().equals(srcTableName) && tve.getColumnName().equals(partitionColName)) {
                                    // The partition column is set to destColumnArray.get(i), because we have the restriction
                                    // that the non-aggregate columns must come at the very begining, and must exactly match
                                    // the group-by columns.
                                    // If we are going to remove this restriction in the future, then we need to do more work
                                    // in order to find a proper partition column.
                                    destTable.setPartitioncolumn(destColumnArray.get(i));
                                    break;
                                }
                            }
                        }
                    } else {
                        for (int i = 0; i < stmt.groupByColumns().size(); i++) {
                            ParsedColInfo gbcol = stmt.groupByColumns().get(i);
                            if (gbcol.tableName.equals(srcTableName) && gbcol.columnName.equals(partitionColName)) {
                                destTable.setPartitioncolumn(destColumnArray.get(i));
                                break;
                            }
                        }
                    }
                }
            // end find partition column
            }
            // end for each source table
            compileFallbackQueriesAndUpdateCatalog(db, query, fallbackQueryXMLs, mvHandlerInfo);
            compileCreateQueryAndUpdateCatalog(db, query, xmlquery, mvHandlerInfo);
            mvHandlerInfo.setGroupbycolumncount(stmt.groupByColumns().size());
            for (int i = 0; i < stmt.m_displayColumns.size(); i++) {
                ParsedColInfo col = stmt.m_displayColumns.get(i);
                Column destColumn = destColumnArray.get(i);
                setTypeAttributesForColumn(destColumn, col.expression);
                // Set the expression type here to determine the behavior of the merge function.
                destColumn.setAggregatetype(col.expression.getExpressionType().getValue());
            }
            mvHandlerInfo.setIssafewithnonemptysources(isSafeForDDL);
        } else {
            // =======================================================================================
            // Materialized view on single table
            // create the materializedviewinfo catalog node for the source table
            Table srcTable = stmt.m_tableList.get(0);
            MaterializedViewInfo matviewinfo = srcTable.getViews().add(viewName);
            matviewinfo.setDest(destTable);
            AbstractExpression where = stmt.getSingleTableFilterExpression();
            if (where != null) {
                String hex = Encoder.hexEncode(where.toJSONString());
                matviewinfo.setPredicate(hex);
            } else {
                matviewinfo.setPredicate("");
            }
            List<Column> srcColumnArray = CatalogUtil.getSortedCatalogItems(srcTable.getColumns(), "index");
            if (stmt.hasComplexGroupby()) {
                // Parse group by expressions to json string
                String groupbyExprsJson = null;
                try {
                    groupbyExprsJson = DDLCompiler.convertToJSONArray(groupbyExprs);
                } catch (JSONException e) {
                    throw m_compiler.new VoltCompilerException("Unexpected error serializing non-column " + "expressions for group by expressions: " + e.toString());
                }
                matviewinfo.setGroupbyexpressionsjson(groupbyExprsJson);
            } else {
                // add the group by columns from the src table
                for (int i = 0; i < stmt.groupByColumns().size(); i++) {
                    ParsedColInfo gbcol = stmt.groupByColumns().get(i);
                    Column srcCol = srcColumnArray.get(gbcol.index);
                    ColumnRef cref = matviewinfo.getGroupbycols().add(srcCol.getTypeName());
                    // groupByColumns is iterating in order of groups. Store that grouping order
                    // in the column ref index. When the catalog is serialized, it will, naturally,
                    // scramble this order like a two year playing dominos, presenting the data
                    // in a meaningless sequence.
                    // the column offset in the view's grouping order
                    cref.setIndex(i);
                    // the source column from the base (non-view) table
                    cref.setColumn(srcCol);
                    // parse out the group by columns into the dest table
                    ParsedColInfo col = stmt.m_displayColumns.get(i);
                    Column destColumn = destColumnArray.get(i);
                    processMaterializedViewColumn(srcTable, destColumn, ExpressionType.VALUE_TUPLE, (TupleValueExpression) col.expression);
                }
            }
            // Set up COUNT(*) column
            ParsedColInfo countCol = stmt.m_displayColumns.get(stmt.groupByColumns().size());
            assert (countCol.expression.getExpressionType() == ExpressionType.AGGREGATE_COUNT_STAR);
            assert (countCol.expression.getLeft() == null);
            processMaterializedViewColumn(srcTable, destColumnArray.get(stmt.groupByColumns().size()), ExpressionType.AGGREGATE_COUNT_STAR, null);
            // prepare info for aggregation columns.
            List<AbstractExpression> aggregationExprs = new ArrayList<>();
            boolean hasAggregationExprs = false;
            ArrayList<AbstractExpression> minMaxAggs = new ArrayList<>();
            for (int i = stmt.groupByColumns().size() + 1; i < stmt.m_displayColumns.size(); i++) {
                ParsedColInfo col = stmt.m_displayColumns.get(i);
                AbstractExpression aggExpr = col.expression.getLeft();
                if (aggExpr.getExpressionType() != ExpressionType.VALUE_TUPLE) {
                    hasAggregationExprs = true;
                }
                aggregationExprs.add(aggExpr);
                if (col.expression.getExpressionType() == ExpressionType.AGGREGATE_MIN || col.expression.getExpressionType() == ExpressionType.AGGREGATE_MAX) {
                    minMaxAggs.add(aggExpr);
                }
            }
            compileFallbackQueriesAndUpdateCatalog(db, query, fallbackQueryXMLs, matviewinfo);
            // set Aggregation Expressions.
            if (hasAggregationExprs) {
                String aggregationExprsJson = null;
                try {
                    aggregationExprsJson = DDLCompiler.convertToJSONArray(aggregationExprs);
                } catch (JSONException e) {
                    throw m_compiler.new VoltCompilerException("Unexpected error serializing non-column " + "expressions for aggregation expressions: " + e.toString());
                }
                matviewinfo.setAggregationexpressionsjson(aggregationExprsJson);
            }
            // Find index for each min/max aggCol/aggExpr (ENG-6511 and ENG-8512)
            for (Integer i = 0; i < minMaxAggs.size(); ++i) {
                Index found = findBestMatchIndexForMatviewMinOrMax(matviewinfo, srcTable, groupbyExprs, minMaxAggs.get(i));
                IndexRef refFound = matviewinfo.getIndexforminmax().add(i.toString());
                if (found != null) {
                    refFound.setName(found.getTypeName());
                } else {
                    refFound.setName("");
                }
            }
            // The COUNT(*) should return a BIGINT column, whereas we found here the COUNT(*) was assigned a INTEGER column.
            for (int i = 0; i <= stmt.groupByColumns().size(); i++) {
                ParsedColInfo col = stmt.m_displayColumns.get(i);
                Column destColumn = destColumnArray.get(i);
                setTypeAttributesForColumn(destColumn, col.expression);
            }
            // parse out the aggregation columns into the dest table
            for (int i = stmt.groupByColumns().size() + 1; i < stmt.m_displayColumns.size(); i++) {
                ParsedColInfo col = stmt.m_displayColumns.get(i);
                Column destColumn = destColumnArray.get(i);
                AbstractExpression colExpr = col.expression.getLeft();
                TupleValueExpression tve = null;
                if (colExpr.getExpressionType() == ExpressionType.VALUE_TUPLE) {
                    tve = (TupleValueExpression) colExpr;
                }
                processMaterializedViewColumn(srcTable, destColumn, col.expression.getExpressionType(), tve);
                setTypeAttributesForColumn(destColumn, col.expression);
            }
            if (srcTable.getPartitioncolumn() != null) {
                // Set the partitioning of destination tables of associated views.
                // If a view's source table is replicated, then a full scan of the
                // associated view is single-sited. If the source is partitioned,
                // a full scan of the view must be distributed, unless it is filtered
                // by the original table's partitioning key, which, to be filtered,
                // must also be a GROUP BY key.
                destTable.setIsreplicated(false);
                setGroupedTablePartitionColumn(matviewinfo, srcTable.getPartitioncolumn());
            }
            matviewinfo.setIssafewithnonemptysources(isSafeForDDL);
        }
    // end if single table view materialized view.
    }
}