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ASF GitHub Bot commented on DRILL-5660: --------------------------------------- Github user vdiravka commented on a diff in the pull request: https://github.com/apache/drill/pull/877#discussion_r129104084 --- Diff: exec/java-exec/src/main/java/org/apache/drill/exec/store/parquet/Metadata.java --- @@ -132,23 +135,57 @@ public static ParquetTableMetadata_v3 getParquetTableMetadata(FileSystem fs, } /** - * Get the parquet metadata for a directory by reading the metadata file + * Get the parquet metadata for the table by reading the metadata file * - * @param fs + * @param fs current file system * @param path The path to the metadata file, located in the directory that contains the parquet files - * @return - * @throws IOException + * @param metaContext metadata context + * @param formatConfig parquet format plugin configs + * @return parquet table metadata + * @throws IOException if metadata file can't be read or updated */ - public static ParquetTableMetadataBase readBlockMeta(FileSystem fs, String path, MetadataContext metaContext, ParquetFormatConfig formatConfig) throws IOException { - Metadata metadata = new Metadata(fs, formatConfig); - metadata.readBlockMeta(path, false, metaContext); - return metadata.parquetTableMetadata; + public static @Nullable ParquetTableMetadataBase readBlockMeta(FileSystem fs, Path path, MetadataContext metaContext, + ParquetFormatConfig formatConfig) { + if (metaContext.isMetaCacheFileCorrect) { + Metadata metadata = new Metadata(fs, formatConfig); + try { + metadata.readBlockMeta(path, false, metaContext); + return metadata.parquetTableMetadata; + } catch (IOException e) { + logger.error(e.toString()); + metaContext.isMetaCacheFileCorrect = false; + } + } + logger.warn("Ignoring unsupported or corrupted metadata file version. Query performance may be slow. Make sure " + + "the cache file is up-to-date by running the REFRESH TABLE METADATA command"); + return null; } - public static ParquetTableMetadataDirs readMetadataDirs(FileSystem fs, String path, MetadataContext metaContext, ParquetFormatConfig formatConfig) throws IOException { - Metadata metadata = new Metadata(fs, formatConfig); - metadata.readBlockMeta(path, true, metaContext); - return metadata.parquetTableMetadataDirs; + /** + * Get the parquet metadata for all subdirectories by reading the metadata file + * + * @param fs current file system + * @param path The path to the metadata file, located in the directory that contains the parquet files + * @param metaContext metadata context + * @param formatConfig parquet format plugin configs + * @return parquet metadata for a directory + * @throws IOException if metadata file can't be read or updated + */ + public static @Nullable ParquetTableMetadataDirs readMetadataDirs(FileSystem fs, Path path, + MetadataContext metaContext, ParquetFormatConfig formatConfig) { + if (metaContext.isMetaDirsCacheFileCorrect) { + Metadata metadata = new Metadata(fs, formatConfig); + try { + metadata.readBlockMeta(path, true, metaContext); + return metadata.parquetTableMetadataDirs; + } catch (IOException e) { + logger.error(e.toString()); --- End diff -- Done > Drill 1.10 queries fail due to Parquet Metadata "corruption" from DRILL-3867 > ---------------------------------------------------------------------------- > > Key: DRILL-5660 > URL: https://issues.apache.org/jira/browse/DRILL-5660 > Project: Apache Drill > Issue Type: Bug > Affects Versions: 1.11.0 > Reporter: Paul Rogers > Assignee: Vitalii Diravka > Labels: doc-impacting > > Drill recently accepted a PR for the following bug: > DRILL-3867: Store relative paths in metadata file > This PR turned out to have a flaw which affects version compatibility. > The DRILL-3867 PR changed the format of Parquet metadata files to store > relative paths. All Drill servers after that PR create files with relative > paths. But, the version number of the file is unchanged, so that older > Drillbits don't know that they can't understand the file. > Instead, if an older Drill tries to read the file, queries fail left and > right. Drill will resolve the paths, but does so relative to the user's HDFS > home directory, which is wrong. > What should have happened is that we should have bumped the parquet metadata > file version number so that older Drillbits can’t read the file. This ticket > requests that we do that. > Now, one could argue that the lack of version number change is fine. Once a > user upgrades Drill, they won't use an old Drillbit. But, things are not that > simple: > * A developer tests a branch based on a pre-DRILL-3867 build on a cluster in > which metadata files have been created by a post-DRILL-3867 build. (This has > already occurred multiple times in our shop.) > * A user tries to upgrade to Drill 1.11, finds an issue, and needs to roll > back to Drill 1.10. Doing so will cause queries to fail due to > seemingly-corrupt metadata files. > * A user tries to do a rolling upgrade: running 1.11 on some servers, 1.10 on > others. Once a 1.11 server is installed, the metadata is updated ("corrupted" > from the perspective of 1.10) and queries fail. > Standard practice in this scenario is to: > * Bump the file version number when the file format changes, and > * Software refuses to read files with a version newer than the software was > designed for. > Of course, it is highly desirable that newer servers read old files, but that > is not the issue here. -- This message was sent by Atlassian JIRA (v6.4.14#64029)