Examples with VectorValueExpression org.voltdb.expressions.VectorValueExpression used on opensource projects

Example 1 with VectorValueExpression

use of org.voltdb.expressions.VectorValueExpression in project voltdb by VoltDB.

the class AbstractParsedStmt method parseVectorExpression.

/**
     * Parse a Vector value for SQL-IN
     */
private AbstractExpression parseVectorExpression(VoltXMLElement exprNode) {
    ArrayList<AbstractExpression> args = new ArrayList<>();
    for (VoltXMLElement argNode : exprNode.children) {
        assert (argNode != null);
        // recursively parse each argument subtree (could be any kind of expression).
        AbstractExpression argExpr = parseExpressionNode(argNode);
        assert (argExpr != null);
        args.add(argExpr);
    }
    VectorValueExpression vve = new VectorValueExpression();
    vve.setValueType(VoltType.VOLTTABLE);
    vve.setArgs(args);
    return vve;
}

Example 2 with VectorValueExpression

use of org.voltdb.expressions.VectorValueExpression in project voltdb by VoltDB.

the class SubPlanAssembler method getIndexableExpressionFromFilters.

/**
     * For a given filter expression, return a normalized version of it that is always a comparison operator whose
     * left-hand-side references the table specified and whose right-hand-side does not.
     * Returns null if no such formulation of the filter expression is possible.
     * For example, "WHERE F_ID = 2" would return it input intact if F_ID is in the table passed in.
     * For join expressions like, "WHERE F_ID = Q_ID", it would also return the input expression if F_ID is in the table
     * but Q_ID is not. If only Q_ID were defined for the table, it would return an expression for (Q_ID = F_ID).
     * If both Q_ID and F_ID were defined on the table, null would be returned.
     * Ideally, the left-hand-side expression is intended to be an indexed expression on the table using the current
     * index. To help reduce false positives, the (base) columns and/or indexed expressions of the index are also
     * provided to help further reduce non-null returns in uninteresting cases.
     *
     * @param targetComparator An allowed comparison operator
     *                         -- its reverse is allowed in reversed expressions
     * @param altTargetComparator An alternatively allowed comparison operator
     *                            -- its reverse is allowed in reversed expressions
     * @param coveringExpr The indexed expression on the table's column
     *                     that might match a query filter, possibly null.
     * @param coveringColId When coveringExpr is null,
     *                      the id of the indexed column might match a query filter.
     * @param tableScan The table scan on which the indexed expression is based
     * @param filtersToCover the query conditions that may contain the desired filter
     * @param allowIndexedJoinFilters Whether filters referencing other tables' columns are acceptable
     * @param filterAction the desired disposition of the matched filter,
                           either EXCLUDE_FROM_POST_FILTERS or KEEP_IN_POST_FILTERS
     * @return An IndexableExpression -- really just a pairing of a normalized form of expr with the
     * potentially indexed expression on the left-hand-side and the potential index key expression on
     * the right of a comparison operator, and a list of parameter bindings that are required for the
     * index scan to be applicable.
     * -- or null if there is no filter that matches the indexed expression
     */
private static IndexableExpression getIndexableExpressionFromFilters(ExpressionType targetComparator, ExpressionType altTargetComparator, AbstractExpression coveringExpr, int coveringColId, StmtTableScan tableScan, List<AbstractExpression> filtersToCover, boolean allowIndexedJoinFilters, boolean filterAction) {
    List<AbstractExpression> binding = null;
    AbstractExpression indexableExpr = null;
    AbstractExpression otherExpr = null;
    ComparisonExpression normalizedExpr = null;
    AbstractExpression originalFilter = null;
    for (AbstractExpression filter : filtersToCover) {
        // ENG-8203: Not going to try to use index with sub-query expression
        if (filter.hasSubquerySubexpression()) {
            // SelectSubqueryExpression also can be scalar sub-query
            continue;
        }
        // Expression type must be resolvable by an index scan
        if ((filter.getExpressionType() == targetComparator) || (filter.getExpressionType() == altTargetComparator)) {
            normalizedExpr = (ComparisonExpression) filter;
            indexableExpr = filter.getLeft();
            otherExpr = filter.getRight();
            binding = bindingIfValidIndexedFilterOperand(tableScan, indexableExpr, otherExpr, coveringExpr, coveringColId);
            if (binding != null) {
                if (!allowIndexedJoinFilters) {
                    if (otherExpr.hasTupleValueSubexpression()) {
                        // This filter can not be used with the index, possibly due to interactions
                        // wih IN LIST processing that would require a three-way NLIJ.
                        binding = null;
                        continue;
                    }
                }
                // Additional restrictions apply to LIKE pattern arguments
                if (targetComparator == ExpressionType.COMPARE_LIKE) {
                    if (otherExpr instanceof ParameterValueExpression) {
                        ParameterValueExpression pve = (ParameterValueExpression) otherExpr;
                        // Can't use an index for parameterized LIKE filters,
                        // e.g. "T1.column LIKE ?"
                        // UNLESS the parameter was artificially substituted
                        // for a user-specified constant AND that constant was a prefix pattern.
                        // In that case, the parameter has to be added to the bound list
                        // for this index/statement.
                        ConstantValueExpression cve = pve.getOriginalValue();
                        if (cve == null || !cve.isPrefixPatternString()) {
                            // the filter is not usable, so the binding is invalid
                            binding = null;
                            continue;
                        }
                        // Remember that the binding list returned by
                        // bindingIfValidIndexedFilterOperand above
                        // is often a "shared object" and is intended to be treated as immutable.
                        // To add a parameter to it, first copy the List.
                        List<AbstractExpression> moreBinding = new ArrayList<>(binding);
                        moreBinding.add(pve);
                        binding = moreBinding;
                    } else if (otherExpr instanceof ConstantValueExpression) {
                        // Can't use an index for non-prefix LIKE filters,
                        // e.g. " T1.column LIKE '%ish' "
                        ConstantValueExpression cve = (ConstantValueExpression) otherExpr;
                        if (!cve.isPrefixPatternString()) {
                            // The constant is not an index-friendly prefix pattern.
                            // the filter is not usable, so the binding is invalid
                            binding = null;
                            continue;
                        }
                    } else {
                        // Other cases are not indexable, e.g. " T1.column LIKE T2.column "
                        // the filter is not usable, so the binding is invalid
                        binding = null;
                        continue;
                    }
                }
                if (targetComparator == ExpressionType.COMPARE_IN) {
                    if (otherExpr.hasTupleValueSubexpression()) {
                        // This is a fancy edge case where the expression could only be indexed
                        // if it:
                        // A) does not reference the indexed table and
                        // B) has ee support for a three-way NLIJ where the table referenced in
                        // the list element expression feeds values from its current row to the
                        // Materialized scan which then re-evaluates its expressions to
                        // re-populate the temp table that drives the injected NLIJ with
                        // this index scan.
                        // This is a slightly more twisted variant of the three-way NLIJ that
                        // would be needed to support compound key indexing on a combination
                        // of (fixed) IN LIST elements and join key values from other tables.
                        // Punt for now on indexing this IN LIST filter.
                        // the filter is not usable, so the binding is invalid
                        binding = null;
                        continue;
                    }
                    if (otherExpr instanceof ParameterValueExpression) {
                    // It's OK to use an index for a parameterized IN filter,
                    // e.g. "T1.column IN ?"
                    // EVEN if the parameter was -- someday -- artificially substituted
                    // for an entire user-specified list of constants.
                    // As of now, that is beyond the capabilities of the ad hoc statement
                    // parameterizer, so "T1.column IN (3, 4)" can use the plan for
                    // "T1.column IN (?, ?)" that might have been originally cached for
                    // "T1.column IN (1, 2)" but "T1.column IN (1, 2, 3)" would need its own
                    // "T1.column IN (?, ?, ?)" plan, etc. per list element count.
                    } else //TODO: Some day, there may be an optimization here that allows an entire
                    // IN LIST of constants to be serialized as a single value instead of a
                    // VectorValue composed of ConstantValue arguments.
                    // What's TBD is whether that would get its own AbstractExpression class or
                    // just be a special case of ConstantValueExpression.
                    {
                        assert (otherExpr instanceof VectorValueExpression);
                    }
                }
                originalFilter = filter;
                if (filterAction == EXCLUDE_FROM_POST_FILTERS) {
                    filtersToCover.remove(filter);
                }
                break;
            }
        }
        if ((filter.getExpressionType() == ComparisonExpression.reverses.get(targetComparator)) || (filter.getExpressionType() == ComparisonExpression.reverses.get(altTargetComparator))) {
            normalizedExpr = (ComparisonExpression) filter;
            normalizedExpr = normalizedExpr.reverseOperator();
            indexableExpr = filter.getRight();
            otherExpr = filter.getLeft();
            binding = bindingIfValidIndexedFilterOperand(tableScan, indexableExpr, otherExpr, coveringExpr, coveringColId);
            if (binding != null) {
                if (!allowIndexedJoinFilters) {
                    if (otherExpr.hasTupleValueSubexpression()) {
                        // This filter can not be used with the index, probably due to interactions
                        // with IN LIST processing of another key component that would require a
                        // three-way NLIJ to be injected.
                        binding = null;
                        continue;
                    }
                }
                originalFilter = filter;
                if (filterAction == EXCLUDE_FROM_POST_FILTERS) {
                    filtersToCover.remove(filter);
                }
                break;
            }
        }
    }
    if (binding == null) {
        // ran out of candidate filters.
        return null;
    }
    return new IndexableExpression(originalFilter, normalizedExpr, binding);
}

Example 3 with VectorValueExpression

use of org.voltdb.expressions.VectorValueExpression in project voltdb by VoltDB.

the class SubPlanAssembler method injectIndexedJoinWithMaterializedScan.

// Generate a plan for an IN-LIST-driven index scan
private static AbstractPlanNode injectIndexedJoinWithMaterializedScan(AbstractExpression listElements, IndexScanPlanNode scanNode) {
    MaterializedScanPlanNode matScan = new MaterializedScanPlanNode();
    assert (listElements instanceof VectorValueExpression || listElements instanceof ParameterValueExpression);
    matScan.setRowData(listElements);
    matScan.setSortDirection(scanNode.getSortDirection());
    NestLoopIndexPlanNode nlijNode = new NestLoopIndexPlanNode();
    nlijNode.setJoinType(JoinType.INNER);
    nlijNode.addInlinePlanNode(scanNode);
    nlijNode.addAndLinkChild(matScan);
    // resolve the sort direction
    nlijNode.resolveSortDirection();
    return nlijNode;
}