/**
* Returns statistics on this table as a tabular result set. Used for the SHOW TABLE STATS
* statement. The schema of the returned TResultSet is set inside this method.
*/
public TResultSet getTableStats() {
TResultSet result = new TResultSet();
TResultSetMetadata resultSchema = new TResultSetMetadata();
result.setSchema(resultSchema);
resultSchema.addToColumns(new TColumn("Region Location", ColumnType.STRING.toThrift()));
resultSchema.addToColumns(new TColumn("Start RowKey", ColumnType.STRING.toThrift()));
resultSchema.addToColumns(new TColumn("Est. #Rows", ColumnType.BIGINT.toThrift()));
resultSchema.addToColumns(new TColumn("Size", ColumnType.STRING.toThrift()));
// TODO: Consider fancier stats maintenance techniques for speeding up this process.
// Currently, we list all regions and perform a mini-scan of each of them to
// estimate the number of rows, the data size, etc., which is rather expensive.
try {
long totalNumRows = 0;
long totalHdfsSize = 0;
List<HRegionLocation> regions =
HBaseTable.getRegionsInRange(
hTable_, HConstants.EMPTY_END_ROW, HConstants.EMPTY_START_ROW);
for (HRegionLocation region : regions) {
TResultRowBuilder rowBuilder = new TResultRowBuilder();
HRegionInfo regionInfo = region.getRegionInfo();
Pair<Long, Long> estRowStats =
getEstimatedRowStats(regionInfo.getStartKey(), regionInfo.getEndKey());
long numRows = estRowStats.first.longValue();
long hdfsSize = getHdfsSize(regionInfo);
totalNumRows += numRows;
totalHdfsSize += hdfsSize;
// Add the region location, start rowkey, number of rows and raw Hdfs size.
rowBuilder
.add(String.valueOf(region.getHostname()))
.add(Bytes.toString(regionInfo.getStartKey()))
.add(numRows)
.addBytes(hdfsSize);
result.addToRows(rowBuilder.get());
}
// Total num rows and raw Hdfs size.
if (regions.size() > 1) {
TResultRowBuilder rowBuilder = new TResultRowBuilder();
rowBuilder.add("Total").add("").add(totalNumRows).addBytes(totalHdfsSize);
result.addToRows(rowBuilder.get());
}
} catch (IOException e) {
throw new RuntimeException(e);
}
return result;
}
private static Map<String, List<Row>> createRsRowMap(HTable htable, List<Row> rows)
throws IOException {
Map<String, List<Row>> rowMap = new HashMap<String, List<Row>>();
for (Row row : rows) {
HRegionLocation rl = htable.getRegionLocation(row.getRow());
String hostname = rl.getHostname();
List<Row> recs = rowMap.get(hostname);
if (recs == null) {
recs = new ArrayList<Row>(INITIAL_LIST_SIZE);
rowMap.put(hostname, recs);
}
recs.add(row);
}
return rowMap;
}
private static Map<String, List<Put>> createRsPutMap(HTable htable, List<Put> puts)
throws IOException {
Map<String, List<Put>> putMap = new HashMap<String, List<Put>>();
for (Put put : puts) {
HRegionLocation rl = htable.getRegionLocation(put.getRow());
String hostname = rl.getHostname();
List<Put> recs = putMap.get(hostname);
if (recs == null) {
recs = new ArrayList<Put>(INITIAL_LIST_SIZE);
putMap.put(hostname, recs);
}
recs.add(put);
}
return putMap;
}
