Examples with LimitOperator io.confluent.ksql.physical.pull.operators.LimitOperator used on opensource projects

Example 1 with LimitOperator

use of io.confluent.ksql.physical.pull.operators.LimitOperator in project ksql by confluentinc.

the class PullPhysicalPlanBuilder method buildPullPhysicalPlan.

/**
 * Visits the logical plan top-down to build the physical plan.
 * @param logicalPlanNode the logical plan root node
 * @return the root node of the tree of physical operators
 */
// CHECKSTYLE_RULES.OFF: CyclomaticComplexity
public PullPhysicalPlan buildPullPhysicalPlan(final LogicalPlanNode logicalPlanNode) {
    // CHECKSTYLE_RULES.ON: CyclomaticComplexity
    DataSourceOperator dataSourceOperator = null;
    final OutputNode outputNode = logicalPlanNode.getNode().orElseThrow(() -> new IllegalArgumentException("Need an output node to build a plan"));
    if (!(outputNode instanceof KsqlBareOutputNode)) {
        throw new KsqlException("Pull queries expect the root of the logical plan to be a " + "KsqlBareOutputNode.");
    }
    // We skip KsqlBareOutputNode in the translation since it only applies the LIMIT
    PlanNode currentLogicalNode = outputNode.getSource();
    AbstractPhysicalOperator prevPhysicalOp = null;
    AbstractPhysicalOperator rootPhysicalOp = null;
    while (true) {
        AbstractPhysicalOperator currentPhysicalOp = null;
        if (currentLogicalNode instanceof QueryProjectNode) {
            currentPhysicalOp = translateProjectNode((QueryProjectNode) currentLogicalNode);
        } else if (currentLogicalNode instanceof QueryFilterNode) {
            currentPhysicalOp = translateFilterNode((QueryFilterNode) currentLogicalNode);
            seenSelectOperator = true;
        } else if (currentLogicalNode instanceof QueryLimitNode) {
            currentPhysicalOp = new LimitOperator((QueryLimitNode) currentLogicalNode);
        } else if (currentLogicalNode instanceof DataSourceNode) {
            currentPhysicalOp = translateDataSourceNode((DataSourceNode) currentLogicalNode);
            dataSourceOperator = (DataSourceOperator) currentPhysicalOp;
        } else {
            throw new KsqlException(String.format("Error in translating logical to physical plan for pull queries: unrecognized logical" + " node %s.", currentLogicalNode));
        }
        if (prevPhysicalOp == null) {
            rootPhysicalOp = currentPhysicalOp;
        } else {
            prevPhysicalOp.addChild(currentPhysicalOp);
        }
        prevPhysicalOp = currentPhysicalOp;
        // Exit the loop when a leaf node is reached
        if (currentLogicalNode.getSources().isEmpty()) {
            break;
        }
        if (currentLogicalNode.getSources().size() > 1) {
            throw new KsqlException("Pull queries do not support joins or nested sub-queries yet.");
        }
        currentLogicalNode = currentLogicalNode.getSources().get(0);
    }
    if (dataSourceOperator == null) {
        throw new IllegalStateException("DataSourceOperator cannot be null in Pull physical plan");
    }
    return new PullPhysicalPlan(rootPhysicalOp, (rootPhysicalOp).getLogicalNode().getSchema(), queryId, lookupConstraints, pullPhysicalPlanType, querySourceType, mat, dataSourceOperator);
}