Function selectTiDBTableRegion

dumpling/export/dump.go:1050–1098

(tctx *tcontext.Context, conn *BaseConn, meta TableMeta)

}

func selectTiDBTableRegion(tctx *tcontext.Context, conn *BaseConn, meta TableMeta) (pkFields []string, pkVals [][]string, err error) {
	pkFields, _, err = selectTiDBRowKeyFields(tctx, conn, meta, checkTiDBTableRegionPkFields)
	if err != nil {
		return
	}

	var (
		startKey, decodedKey sql.NullString
		rowID                = -1
	)
	const (
		tableRegionSQL = "SELECT START_KEY,tidb_decode_key(START_KEY) from INFORMATION_SCHEMA.TIKV_REGION_STATUS s WHERE s.DB_NAME = ? AND s.TABLE_NAME = ? AND IS_INDEX = 0 ORDER BY START_KEY;"
		tidbRowID      = "_tidb_rowid="
	)
	dbName, tableName := meta.DatabaseName(), meta.TableName()
	logger := tctx.L().With(zap.String("database", dbName), zap.String("table", tableName))
	err = conn.QuerySQL(tctx, func(rows *sql.Rows) error {
		rowID++
		err = rows.Scan(&startKey, &decodedKey)
		if err != nil {
			return errors.Trace(err)
		}
		// first region's start key has no use. It may come from another table or might be invalid
		if rowID == 0 {
			return nil
		}
		if !startKey.Valid {
			logger.Debug("meet invalid start key", zap.Int("rowID", rowID))
			return nil
		}
		if !decodedKey.Valid {
			logger.Debug("meet invalid decoded start key", zap.Int("rowID", rowID), zap.String("startKey", startKey.String))
			return nil
		}
		pkVal, err2 := extractTiDBRowIDFromDecodedKey(tidbRowID, decodedKey.String)
		if err2 != nil {
			logger.Debug("cannot extract pkVal from decoded start key",
				zap.Int("rowID", rowID), zap.String("startKey", startKey.String), zap.String("decodedKey", decodedKey.String), log.ShortError(err2))
		} else {
			pkVals = append(pkVals, []string{pkVal})
		}
		return nil
	}, func() {
		pkFields = pkFields[:0]
		pkVals = pkVals[:0]
	}, tableRegionSQL, dbName, tableName)

	return pkFields, pkVals, errors.Trace(err)
}

func selectTiDBPartitionRegion(tctx *tcontext.Context, conn *BaseConn, dbName, tableName, partition string) (pkVals [][]string, err error) {
	var startKeys [][]string