/**
* 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.tajo.storage;
import org.apache.tajo.catalog.Schema;
import org.apache.tajo.catalog.statistics.ColumnStat;
import org.apache.tajo.catalog.statistics.TableStat;
import org.apache.tajo.common.TajoDataTypes.DataType;
import org.apache.tajo.common.TajoDataTypes.Type;
import org.apache.tajo.datum.Datum;
import org.apache.tajo.datum.NullDatum;
/**
* This class is not thread-safe.
*/
public class TableStatistics {
private Schema schema;
private Tuple minValues;
private Tuple maxValues;
private long [] numNulls;
private long numRows = 0;
private long numBytes = 0;
private boolean [] comparable;
public TableStatistics(Schema schema) {
this.schema = schema;
minValues = new VTuple(schema.getColumnNum());
maxValues = new VTuple(schema.getColumnNum());
numNulls = new long[schema.getColumnNum()];
comparable = new boolean[schema.getColumnNum()];
DataType type;
for (int i = 0; i < schema.getColumnNum(); i++) {
type = schema.getColumn(i).getDataType();
if (type.getType() == Type.PROTOBUF) {
comparable[i] = false;
} else {
comparable[i] = true;
}
}
}
public Schema getSchema() {
return this.schema;
}
public void incrementRow() {
numRows++;
}
public long getNumRows() {
return this.numRows;
}
public void setNumBytes(long bytes) {
this.numBytes = bytes;
}
public long getNumBytes() {
return this.numBytes;
}
public void analyzeField(int idx, Datum datum) {
if (datum instanceof NullDatum) {
numNulls[idx]++;
return;
}
if (comparable[idx]) {
if (!maxValues.contains(idx) ||
maxValues.get(idx).compareTo(datum) < 0) {
maxValues.put(idx, datum);
}
if (!minValues.contains(idx) ||
minValues.get(idx).compareTo(datum) > 0) {
minValues.put(idx, datum);
}
}
}
public TableStat getTableStat() {
TableStat stat = new TableStat();
ColumnStat columnStat;
for (int i = 0; i < schema.getColumnNum(); i++) {
columnStat = new ColumnStat(schema.getColumn(i));
columnStat.setNumNulls(numNulls[i]);
columnStat.setMinValue(minValues.get(i));
columnStat.setMaxValue(maxValues.get(i));
stat.addColumnStat(columnStat);
}
stat.setNumRows(this.numRows);
stat.setNumBytes(this.numBytes);
return stat;
}
}