/**
* 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 void checkHBaseTableCols(
Db db,
String hiveTableName,
String hbaseTableName,
String[] hiveColNames,
String[] colFamilies,
String[] colQualifiers,
ColumnType[] colTypes)
throws TableLoadingException {
checkTableCols(db, hiveTableName, 1, hiveColNames, colTypes);
HBaseTable tbl = (HBaseTable) db.getTable(hiveTableName);
assertEquals(tbl.getHBaseTableName(), hbaseTableName);
List<Column> cols = tbl.getColumns();
assertEquals(colFamilies.length, colTypes.length);
assertEquals(colQualifiers.length, colTypes.length);
Iterator<Column> it = cols.iterator();
int i = 0;
while (it.hasNext()) {
HBaseColumn col = (HBaseColumn) it.next();
assertEquals(col.getColumnFamily(), colFamilies[i]);
assertEquals(col.getColumnQualifier(), colQualifiers[i]);
++i;
}
}
