示例#1
0
// encodeSecondaryIndexes encodes the secondary index keys. The
// secondaryIndexEntries are only valid until the next call to encodeIndexes or
// encodeSecondaryIndexes.
func (rh *rowHelper) encodeSecondaryIndexes(
	colIDtoRowIndex map[sqlbase.ColumnID]int, values []parser.Datum,
) (secondaryIndexEntries []sqlbase.IndexEntry, err error) {
	if len(rh.indexEntries) != len(rh.indexes) {
		rh.indexEntries = make([]sqlbase.IndexEntry, len(rh.indexes))
	}
	err = sqlbase.EncodeSecondaryIndexes(
		rh.tableDesc, rh.indexes, colIDtoRowIndex, values, rh.indexEntries)
	if err != nil {
		return nil, err
	}
	return rh.indexEntries, nil
}
示例#2
0
文件: backfill.go 项目: knz/cockroach
// backfillIndexesChunk returns the next-key, done and an error. next-key and
// done are invalid if error != nil. next-key is invalid if done is true.
func (sc *SchemaChanger) backfillIndexesChunk(
	added []sqlbase.IndexDescriptor,
	sp roachpb.Span,
	chunkSize int64,
	mutationIdx int,
	lastCheckpoint *time.Time,
) (roachpb.Key, bool, error) {
	var nextKey roachpb.Key
	done := false
	secondaryIndexEntries := make([]sqlbase.IndexEntry, len(added))
	err := sc.db.Txn(context.TODO(), func(txn *client.Txn) error {
		if sc.testingKnobs.RunBeforeBackfillChunk != nil {
			if err := sc.testingKnobs.RunBeforeBackfillChunk(sp); err != nil {
				return err
			}
		}
		if sc.testingKnobs.RunAfterBackfillChunk != nil {
			defer sc.testingKnobs.RunAfterBackfillChunk()
		}

		tableDesc, err := sqlbase.GetTableDescFromID(txn, sc.tableID)
		if err != nil {
			return err
		}
		// Short circuit the backfill if the table has been deleted.
		if done = tableDesc.Dropped(); done {
			return nil
		}

		// Get the next set of rows.
		// TODO(tamird): Support partial indexes?
		//
		// Use a scanNode with SELECT to pass in a sqlbase.TableDescriptor
		// to the SELECT without needing to go through table name
		// resolution, because we want to run schema changes from a gossip
		// feed of table IDs. Running the scan and applying the changes in
		// many transactions is fine because the schema change is in the
		// correct state to handle intermediate OLTP commands which delete
		// and add values during the scan.
		planner := makePlanner("backfill")
		planner.setTxn(txn)
		scan := planner.Scan()
		scan.desc = *tableDesc
		scan.spans = []roachpb.Span{sp}
		scan.SetLimitHint(chunkSize, false)
		scan.initDescDefaults(publicAndNonPublicColumns)
		rows, err := selectIndex(scan, nil, false)
		if err != nil {
			return err
		}

		if err := rows.Start(); err != nil {
			return err
		}

		// Construct a map from column ID to the index the value appears at
		// within a row.
		colIDtoRowIndex, err := makeColIDtoRowIndex(rows, tableDesc)
		if err != nil {
			return err
		}
		b := &client.Batch{}
		numRows := int64(0)
		for ; numRows < chunkSize; numRows++ {
			if next, err := rows.Next(); !next {
				if err != nil {
					return err
				}
				break
			}
			rowVals := rows.Values()

			err := sqlbase.EncodeSecondaryIndexes(
				tableDesc, added, colIDtoRowIndex,
				rowVals, secondaryIndexEntries)
			if err != nil {
				return err
			}
			for _, secondaryIndexEntry := range secondaryIndexEntries {
				if log.V(2) {
					log.Infof(txn.Context, "InitPut %s -> %v", secondaryIndexEntry.Key,
						secondaryIndexEntry.Value)
				}
				b.InitPut(secondaryIndexEntry.Key, &secondaryIndexEntry.Value)
			}
		}
		// Write the new index values.
		if err := txn.Run(b); err != nil {
			return convertBackfillError(tableDesc, b)
		}
		// Have we processed all the table rows?
		if done = numRows < chunkSize; done {
			return nil
		}
		// Keep track of the next key.
		resume := roachpb.Span{Key: scan.fetcher.Key(), EndKey: sp.EndKey}
		if err := sc.maybeWriteResumeSpan(txn, tableDesc, resume, mutationIdx, lastCheckpoint); err != nil {
			return err
		}
		nextKey = resume.Key
		return nil
	})
	return nextKey, done, err
}