| // 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.impala.analysis; |
| |
| import static java.lang.String.format; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| import org.apache.impala.common.Pair; |
| import org.apache.impala.planner.DataSink; |
| import org.apache.impala.planner.TableSink; |
| import org.apache.impala.thrift.TSortingOrder; |
| |
| import com.google.common.base.Preconditions; |
| import com.google.common.collect.ImmutableList; |
| |
| /** |
| * Representation of an Update statement. |
| * |
| * Example UPDATE statement: |
| * |
| * UPDATE target_table |
| * SET slotRef=expr, [slotRef=expr, ...] |
| * FROM table_ref_list |
| * WHERE conjunct_list |
| * |
| * An update statement consists of four major parts. First, the target table path, |
| * second, the list of assignments, the optional FROM clause, and the optional where |
| * clause. The type of the right-hand side of each assignments must be |
| * assignment compatible with the left-hand side column type. |
| * |
| * Currently, only Kudu tables can be updated. |
| */ |
| public class UpdateStmt extends ModifyStmt { |
| public UpdateStmt(List<String> targetTablePath, FromClause tableRefs, |
| List<Pair<SlotRef, Expr>> assignmentExprs, Expr wherePredicate) { |
| super(targetTablePath, tableRefs, assignmentExprs, wherePredicate); |
| } |
| |
| public UpdateStmt(UpdateStmt other) { |
| super(other.targetTablePath_, other.fromClause_.clone(), |
| new ArrayList<>(), other.wherePredicate_); |
| } |
| |
| /** |
| * Return an instance of a KuduTableSink specialized as an Update operation. |
| */ |
| @Override |
| public DataSink createDataSink(List<Expr> resultExprs) { |
| // analyze() must have been called before. |
| Preconditions.checkState(table_ != null); |
| DataSink dataSink = TableSink.create(table_, TableSink.Op.UPDATE, |
| ImmutableList.<Expr>of(), resultExprs, referencedColumns_, false, false, |
| new Pair<>(ImmutableList.<Integer> of(), TSortingOrder.LEXICAL)); |
| Preconditions.checkState(!referencedColumns_.isEmpty()); |
| return dataSink; |
| } |
| |
| @Override |
| public UpdateStmt clone() { |
| return new UpdateStmt(this); |
| } |
| |
| @Override |
| public String toSql(ToSqlOptions options) { |
| if (!options.showRewritten() && sqlString_ != null) return sqlString_; |
| |
| StringBuilder b = new StringBuilder(); |
| b.append("UPDATE "); |
| |
| if (fromClause_ == null) { |
| b.append(targetTableRef_.toSql(options)); |
| } else { |
| if (targetTableRef_.hasExplicitAlias()) { |
| b.append(targetTableRef_.getExplicitAlias()); |
| } else { |
| b.append(targetTableRef_.toSql(options)); |
| } |
| } |
| b.append(" SET"); |
| |
| boolean first = true; |
| for (Pair<SlotRef, Expr> i : assignments_) { |
| if (!first) { |
| b.append(","); |
| } else { |
| first = false; |
| } |
| b.append(format(" %s = %s", i.first.toSql(options), i.second.toSql(options))); |
| } |
| |
| b.append(fromClause_.toSql(options)); |
| |
| if (wherePredicate_ != null) { |
| b.append(" WHERE "); |
| b.append(wherePredicate_.toSql(options)); |
| } |
| return b.toString(); |
| } |
| } |