| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to you under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.calcite.rex; |
| |
| import org.apache.calcite.plan.RelOptUtil; |
| import org.apache.calcite.rel.RelNode; |
| import org.apache.calcite.rel.type.RelDataType; |
| import org.apache.calcite.rel.type.RelDataTypeFactory; |
| import org.apache.calcite.rel.type.RelDataTypeField; |
| import org.apache.calcite.sql.SqlKind; |
| import org.apache.calcite.sql.SqlOperator; |
| import org.apache.calcite.sql.fun.SqlQuantifyOperator; |
| import org.apache.calcite.sql.fun.SqlStdOperatorTable; |
| import org.apache.calcite.sql.type.SqlTypeName; |
| |
| import com.google.common.collect.ImmutableList; |
| |
| import org.checkerframework.checker.nullness.qual.Nullable; |
| |
| import java.util.List; |
| import java.util.Objects; |
| |
| /** |
| * Scalar expression that represents an IN, EXISTS or scalar sub-query. |
| */ |
| public class RexSubQuery extends RexCall { |
| public final RelNode rel; |
| |
| private RexSubQuery(RelDataType type, SqlOperator op, |
| ImmutableList<RexNode> operands, RelNode rel) { |
| super(type, op, operands); |
| this.rel = rel; |
| } |
| |
| /** Creates an IN sub-query. */ |
| public static RexSubQuery in(RelNode rel, ImmutableList<RexNode> nodes) { |
| final RelDataType type = type(rel, nodes); |
| return new RexSubQuery(type, SqlStdOperatorTable.IN, nodes, rel); |
| } |
| |
| /** Creates a SOME sub-query. |
| * |
| * <p>There is no ALL. For {@code x comparison ALL (sub-query)} use instead |
| * {@code NOT (x inverse-comparison SOME (sub-query))}. |
| * If {@code comparison} is {@code >} |
| * then {@code negated-comparison} is {@code <=}, and so forth. |
| * |
| * <p>Also =SOME is rewritten into IN</p> */ |
| public static RexSubQuery some(RelNode rel, ImmutableList<RexNode> nodes, |
| SqlQuantifyOperator op) { |
| assert op.kind == SqlKind.SOME; |
| |
| if (op == SqlStdOperatorTable.SOME_EQ) { |
| return RexSubQuery.in(rel, nodes); |
| } |
| final RelDataType type = type(rel, nodes); |
| return new RexSubQuery(type, op, nodes, rel); |
| } |
| |
| static RelDataType type(RelNode rel, ImmutableList<RexNode> nodes) { |
| assert rel.getRowType().getFieldCount() == nodes.size(); |
| final RelDataTypeFactory typeFactory = rel.getCluster().getTypeFactory(); |
| boolean nullable = false; |
| for (RexNode node : nodes) { |
| if (node.getType().isNullable()) { |
| nullable = true; |
| } |
| } |
| for (RelDataTypeField field : rel.getRowType().getFieldList()) { |
| if (field.getType().isNullable()) { |
| nullable = true; |
| } |
| } |
| return typeFactory.createTypeWithNullability( |
| typeFactory.createSqlType(SqlTypeName.BOOLEAN), nullable); |
| } |
| |
| /** Creates an EXISTS sub-query. */ |
| public static RexSubQuery exists(RelNode rel) { |
| final RelDataTypeFactory typeFactory = rel.getCluster().getTypeFactory(); |
| final RelDataType type = typeFactory.createSqlType(SqlTypeName.BOOLEAN); |
| return new RexSubQuery(type, SqlStdOperatorTable.EXISTS, |
| ImmutableList.of(), rel); |
| } |
| |
| /** Creates an UNIQUE sub-query. */ |
| public static RexSubQuery unique(RelNode rel) { |
| final RelDataTypeFactory typeFactory = rel.getCluster().getTypeFactory(); |
| final RelDataType type = typeFactory.createSqlType(SqlTypeName.BOOLEAN); |
| return new RexSubQuery(type, SqlStdOperatorTable.UNIQUE, |
| ImmutableList.of(), rel); |
| } |
| |
| /** Creates a scalar sub-query. */ |
| public static RexSubQuery scalar(RelNode rel) { |
| final List<RelDataTypeField> fieldList = rel.getRowType().getFieldList(); |
| assert fieldList.size() == 1; |
| final RelDataTypeFactory typeFactory = rel.getCluster().getTypeFactory(); |
| final RelDataType type = |
| typeFactory.createTypeWithNullability(fieldList.get(0).getType(), true); |
| return new RexSubQuery(type, SqlStdOperatorTable.SCALAR_QUERY, |
| ImmutableList.of(), rel); |
| } |
| |
| @Override public <R> R accept(RexVisitor<R> visitor) { |
| return visitor.visitSubQuery(this); |
| } |
| |
| @Override public <R, P> R accept(RexBiVisitor<R, P> visitor, P arg) { |
| return visitor.visitSubQuery(this, arg); |
| } |
| |
| @Override protected String computeDigest(boolean withType) { |
| final StringBuilder sb = new StringBuilder(op.getName()); |
| sb.append("("); |
| for (RexNode operand : operands) { |
| sb.append(operand); |
| sb.append(", "); |
| } |
| sb.append("{\n"); |
| sb.append(RelOptUtil.toString(rel)); |
| sb.append("})"); |
| return sb.toString(); |
| } |
| |
| @Override public RexSubQuery clone(RelDataType type, List<RexNode> operands) { |
| return new RexSubQuery(type, getOperator(), |
| ImmutableList.copyOf(operands), rel); |
| } |
| |
| public RexSubQuery clone(RelNode rel) { |
| return new RexSubQuery(type, getOperator(), operands, rel); |
| } |
| |
| @Override public boolean equals(@Nullable Object obj) { |
| if (this == obj) { |
| return true; |
| } |
| if (!(obj instanceof RexSubQuery)) { |
| return false; |
| } |
| RexSubQuery sq = (RexSubQuery) obj; |
| return op.equals(sq.op) |
| && operands.equals(sq.operands) |
| && rel.deepEquals(sq.rel); |
| } |
| |
| @Override public int hashCode() { |
| if (hash == 0) { |
| hash = Objects.hash(op, operands, rel.deepHashCode()); |
| } |
| return hash; |
| } |
| } |