Examples with Relation com.facebook.presto.sql.tree.Relation used on opensource projects

Example 1 with Relation

use of com.facebook.presto.sql.tree.Relation in project presto by prestodb.

the class AstBuilder method visitQuerySpecification.

@Override
public Node visitQuerySpecification(SqlBaseParser.QuerySpecificationContext context) {
    Optional<Relation> from = Optional.empty();
    List<SelectItem> selectItems = visit(context.selectItem(), SelectItem.class);
    List<Relation> relations = visit(context.relation(), Relation.class);
    if (!relations.isEmpty()) {
        // synthesize implicit join nodes
        Iterator<Relation> iterator = relations.iterator();
        Relation relation = iterator.next();
        while (iterator.hasNext()) {
            relation = new Join(getLocation(context), Join.Type.IMPLICIT, relation, iterator.next(), Optional.empty());
        }
        from = Optional.of(relation);
    }
    return new QuerySpecification(getLocation(context), new Select(getLocation(context.SELECT()), isDistinct(context.setQuantifier()), selectItems), from, visitIfPresent(context.where, Expression.class), visitIfPresent(context.groupBy(), GroupBy.class), visitIfPresent(context.having, Expression.class), Optional.empty(), Optional.empty(), Optional.empty());
}

Example 2 with Relation

use of com.facebook.presto.sql.tree.Relation in project presto by prestodb.

the class AstBuilder method visitAliasedRelation.

@Override
public Node visitAliasedRelation(SqlBaseParser.AliasedRelationContext context) {
    Relation child = (Relation) visit(context.relationPrimary());
    if (context.identifier() == null) {
        return child;
    }
    List<Identifier> aliases = null;
    if (context.columnAliases() != null) {
        aliases = visit(context.columnAliases().identifier(), Identifier.class);
    }
    return new AliasedRelation(getLocation(context), child, (Identifier) visit(context.identifier()), aliases);
}

Example 3 with Relation

use of com.facebook.presto.sql.tree.Relation in project presto by prestodb.

the class PredicateStitcher method visitJoin.

@Override
protected Node visitJoin(Join node, PredicateStitcherContext context) {
    Relation rewrittenLeft = (Relation) process(node.getLeft(), context);
    Relation rewrittenRight = (Relation) process(node.getRight(), context);
    return new Join(node.getType(), rewrittenLeft, rewrittenRight, node.getCriteria());
}

Example 4 with Relation

use of com.facebook.presto.sql.tree.Relation in project presto by prestodb.

the class AstBuilder method visitJoinRelation.

// *************** from clause *****************
@Override
public Node visitJoinRelation(SqlBaseParser.JoinRelationContext context) {
    Relation left = (Relation) visit(context.left);
    Relation right;
    if (context.CROSS() != null) {
        right = (Relation) visit(context.right);
        return new Join(getLocation(context), Join.Type.CROSS, left, right, Optional.empty());
    }
    JoinCriteria criteria;
    if (context.NATURAL() != null) {
        right = (Relation) visit(context.right);
        criteria = new NaturalJoin();
    } else {
        right = (Relation) visit(context.rightRelation);
        if (context.joinCriteria().ON() != null) {
            criteria = new JoinOn((Expression) visit(context.joinCriteria().booleanExpression()));
        } else if (context.joinCriteria().USING() != null) {
            criteria = new JoinUsing(visit(context.joinCriteria().identifier(), Identifier.class));
        } else {
            throw new IllegalArgumentException("Unsupported join criteria");
        }
    }
    Join.Type joinType;
    if (context.joinType().LEFT() != null) {
        joinType = Join.Type.LEFT;
    } else if (context.joinType().RIGHT() != null) {
        joinType = Join.Type.RIGHT;
    } else if (context.joinType().FULL() != null) {
        joinType = Join.Type.FULL;
    } else {
        joinType = Join.Type.INNER;
    }
    return new Join(getLocation(context), joinType, left, right, Optional.of(criteria));
}

Example 5 with Relation

use of com.facebook.presto.sql.tree.Relation in project presto by prestodb.

the class MaterializedViewQueryOptimizer method visitQuerySpecification.

@Override
protected Node visitQuerySpecification(QuerySpecification node, Void context) {
    if (!node.getFrom().isPresent()) {
        throw new IllegalStateException("Query with no From clause is not rewritable by materialized view");
    }
    Relation relation = node.getFrom().get();
    if (relation instanceof AliasedRelation) {
        removablePrefix = Optional.of(((AliasedRelation) relation).getAlias());
        relation = ((AliasedRelation) relation).getRelation();
    }
    if (!(relation instanceof Table)) {
        throw new SemanticException(NOT_SUPPORTED, node, "Relation other than Table is not supported in query optimizer");
    }
    Table baseTable = (Table) relation;
    if (!removablePrefix.isPresent()) {
        removablePrefix = Optional.of(new Identifier(baseTable.getName().toString()));
    }
    if (node.getGroupBy().isPresent()) {
        ImmutableSet.Builder<Expression> expressionsInGroupByBuilder = ImmutableSet.builder();
        for (GroupingElement element : node.getGroupBy().get().getGroupingElements()) {
            element = removeGroupingElementPrefix(element, removablePrefix);
            Optional<Set<Expression>> groupByOfMaterializedView = materializedViewInfo.getGroupBy();
            if (groupByOfMaterializedView.isPresent()) {
                for (Expression expression : element.getExpressions()) {
                    if (!groupByOfMaterializedView.get().contains(expression) || !materializedViewInfo.getBaseToViewColumnMap().containsKey(expression)) {
                        throw new IllegalStateException(format("Grouping element %s is not present in materialized view groupBy field", element));
                    }
                }
            }
            expressionsInGroupByBuilder.addAll(element.getExpressions());
        }
        expressionsInGroupBy = Optional.of(expressionsInGroupByBuilder.build());
    }
    // TODO: Add HAVING validation to the validator https://github.com/prestodb/presto/issues/16406
    if (node.getHaving().isPresent()) {
        throw new SemanticException(NOT_SUPPORTED, node, "Having clause is not supported in query optimizer");
    }
    if (materializedViewInfo.getWhereClause().isPresent()) {
        if (!node.getWhere().isPresent()) {
            throw new IllegalStateException("Query with no where clause is not rewritable by materialized view with where clause");
        }
        QualifiedObjectName baseTableName = createQualifiedObjectName(session, baseTable, baseTable.getName());
        Optional<TableHandle> tableHandle = metadata.getTableHandle(session, baseTableName);
        if (!tableHandle.isPresent()) {
            throw new SemanticException(MISSING_TABLE, node, "Table does not exist");
        }
        ImmutableList.Builder<Field> fields = ImmutableList.builder();
        for (ColumnHandle columnHandle : metadata.getColumnHandles(session, tableHandle.get()).values()) {
            ColumnMetadata columnMetadata = metadata.getColumnMetadata(session, tableHandle.get(), columnHandle);
            fields.add(Field.newUnqualified(materializedViewInfo.getWhereClause().get().getLocation(), columnMetadata.getName(), columnMetadata.getType()));
        }
        Scope scope = Scope.builder().withRelationType(RelationId.anonymous(), new RelationType(fields.build())).build();
        // Given base query's filter condition and materialized view's filter condition, the goal is to check if MV's filters contain Base's filters (Base implies MV).
        // Let base query's filter condition be A, and MV's filter condition be B.
        // One way to evaluate A implies B is to evaluate logical expression A^~B and check if the output domain is none.
        // If the resulting domain is none, then A^~B is false. Thus A implies B.
        // For more information and examples: https://fb.quip.com/WwmxA40jLMxR
        // TODO: Implement method that utilizes external SAT solver libraries. https://github.com/prestodb/presto/issues/16536
        RowExpression materializedViewWhereCondition = convertToRowExpression(materializedViewInfo.getWhereClause().get(), scope);
        RowExpression baseQueryWhereCondition = convertToRowExpression(node.getWhere().get(), scope);
        RowExpression rewriteLogicExpression = and(baseQueryWhereCondition, call(baseQueryWhereCondition.getSourceLocation(), "not", new FunctionResolution(metadata.getFunctionAndTypeManager()).notFunction(), materializedViewWhereCondition.getType(), materializedViewWhereCondition));
        RowExpression disjunctiveNormalForm = logicalRowExpressions.convertToDisjunctiveNormalForm(rewriteLogicExpression);
        ExtractionResult<VariableReferenceExpression> result = domainTranslator.fromPredicate(session.toConnectorSession(), disjunctiveNormalForm, BASIC_COLUMN_EXTRACTOR);
        if (!result.getTupleDomain().equals(TupleDomain.none())) {
            throw new IllegalStateException("View filter condition does not contain base query's filter condition");
        }
    }
    return new QuerySpecification((Select) process(node.getSelect(), context), node.getFrom().map(from -> (Relation) process(from, context)), node.getWhere().map(where -> (Expression) process(where, context)), node.getGroupBy().map(groupBy -> (GroupBy) process(groupBy, context)), node.getHaving().map(having -> (Expression) process(having, context)), node.getOrderBy().map(orderBy -> (OrderBy) process(orderBy, context)), node.getOffset(), node.getLimit());
}