org.apache.hadoop.hive.ql.index.bitmap.BitmapOuterQuery Maven / Gradle / Ivy
/**
* 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.hadoop.hive.ql.index.bitmap;
import org.apache.hadoop.hive.ql.plan.ExprNodeDesc;
import org.apache.hadoop.hive.ql.index.bitmap.BitmapQuery;
/**
* Representation of the outer query on bitmap indexes that JOINs the result of
* inner SELECT scans on bitmap indexes (represented in BitmapQuery objects)
* using EWAH_* bitwise operations
*/
public class BitmapOuterQuery implements BitmapQuery {
private String alias;
private BitmapQuery lhs;
private BitmapQuery rhs;
private String queryStr;
public BitmapOuterQuery(String alias, BitmapQuery lhs, BitmapQuery rhs) {
this.alias = alias;
this.lhs = lhs;
this.rhs = rhs;
constructQueryStr();
}
public String getAlias() {
return alias;
}
/**
* Return a string representation of the query for compilation
*/
public String toString() {
return queryStr;
}
/**
* Construct a string representation of the query to be compiled
*/
private void constructQueryStr() {
StringBuilder sb = new StringBuilder();
sb.append("(SELECT ");
sb.append(lhs.getAlias());
sb.append(".`_bucketname`, ");
sb.append(rhs.getAlias());
sb.append(".`_offset`, ");
sb.append("EWAH_BITMAP_AND(");
sb.append(lhs.getAlias());
sb.append(".`_bitmaps`, ");
sb.append(rhs.getAlias());
sb.append(".`_bitmaps`) AS `_bitmaps` FROM ");
sb.append(lhs.toString());
sb.append(" JOIN ");
sb.append(rhs.toString());
sb.append(" ON ");
sb.append(lhs.getAlias());
sb.append(".`_bucketname` = ");
sb.append(rhs.getAlias());
sb.append(".`_bucketname` AND ");
sb.append(lhs.getAlias());
sb.append(".`_offset` = ");
sb.append(rhs.getAlias());
sb.append(".`_offset`) ");
sb.append(this.alias);
queryStr = sb.toString();
}
}