Examples with ZetaSqlUnnest org.apache.beam.sdk.extensions.sql.zetasql.unnest.ZetaSqlUnnest used on opensource projects

Example 1 with ZetaSqlUnnest

use of org.apache.beam.sdk.extensions.sql.zetasql.unnest.ZetaSqlUnnest in project beam by apache.

the class ArrayScanToJoinConverter method convert.

/**
 * Returns a LogicJoin.
 */
@Override
public RelNode convert(ResolvedArrayScan zetaNode, List<RelNode> inputs) {
    List<RexNode> projects = new ArrayList<>();
    RelNode leftInput = inputs.get(0);
    ResolvedColumnRef columnRef = (ResolvedColumnRef) zetaNode.getArrayExpr();
    CorrelationId correlationId = getCluster().createCorrel();
    getCluster().getQuery().mapCorrel(correlationId.getName(), leftInput);
    String columnName = String.format("%s%s", zetaNode.getElementColumn().getTableName(), zetaNode.getElementColumn().getName());
    projects.add(getCluster().getRexBuilder().makeFieldAccess(getCluster().getRexBuilder().makeCorrel(leftInput.getRowType(), correlationId), getExpressionConverter().indexOfProjectionColumnRef(columnRef.getColumn().getId(), zetaNode.getInputScan().getColumnList())));
    RelNode projectNode = LogicalProject.create(createOneRow(getCluster()), ImmutableList.of(), projects, ImmutableList.of(columnName));
    // Create an UnCollect
    boolean ordinality = (zetaNode.getArrayOffsetColumn() != null);
    // If they aren't true we need the Project to reorder columns.
    assert zetaNode.getElementColumn().getId() == 1;
    assert !ordinality || zetaNode.getArrayOffsetColumn().getColumn().getId() == 2;
    ZetaSqlUnnest uncollectNode = ZetaSqlUnnest.create(projectNode.getTraitSet(), projectNode, ordinality);
    List<RexInputRef> rightProjects = new ArrayList<>();
    List<String> rightNames = new ArrayList<>();
    rightProjects.add(getCluster().getRexBuilder().makeInputRef(uncollectNode, 0));
    rightNames.add(columnName);
    if (ordinality) {
        rightProjects.add(getCluster().getRexBuilder().makeInputRef(uncollectNode, 1));
        rightNames.add(String.format(zetaNode.getArrayOffsetColumn().getColumn().getTableName(), zetaNode.getArrayOffsetColumn().getColumn().getName()));
    }
    RelNode rightInput = LogicalProject.create(uncollectNode, ImmutableList.of(), rightProjects, rightNames);
    // Join condition should be a RexNode converted from join_expr.
    RexNode condition = getExpressionConverter().convertRexNodeFromResolvedExpr(zetaNode.getJoinExpr());
    JoinRelType joinRelType = zetaNode.getIsOuter() ? JoinRelType.LEFT : JoinRelType.INNER;
    return LogicalJoin.create(leftInput, rightInput, ImmutableList.of(), condition, ImmutableSet.of(), joinRelType, false, ImmutableList.of());
}