4cee2ce251
## What changes were proposed in this pull request? It seems the proximate cause of the test failures is that `cast(str as decimal)` in derby will raise an exception instead of returning NULL. This is a problem since Hive sometimes inserts `__HIVE_DEFAULT_PARTITION__` entries into the partition table as documented here: https://github.com/apache/hive/blob/trunk/metastore/src/java/org/apache/hadoop/hive/metastore/MetaStoreDirectSql.java#L1034 Basically, when these special default partitions are present, partition pruning pushdown using the SQL-direct mode will fail due this cast exception. As commented on in `MetaStoreDirectSql.java` above, this is normally fine since Hive falls back to JDO pruning, however when the pruning predicate contains an unsupported operator such as `>`, that will fail as well. The only remaining question is why this behavior is nondeterministic. We know that when the test flakes, retries do not help, therefore the cause must be environmental. The current best hypothesis is that some config is different between different jenkins runs, which is why this PR prints out the Spark SQL and Hive confs for the test. The hope is that by comparing the config state for failure vs success we can isolate the root cause of the flakiness. **Update:** we could not isolate the issue. It does not seem to be due to configuration differences. As such, I'm going to enable the non-flaky parts of the test since we are fairly confident these issues only occur with Derby (which is not used in production). ## How was this patch tested? N/A Author: Eric Liang <ekl@databricks.com> Closes #15725 from ericl/print-confs-out. |
||
|---|---|---|
| .. | ||
| catalyst | ||
| core | ||
| hive | ||
| hive-thriftserver | ||
| README.md | ||
Spark SQL
This module provides support for executing relational queries expressed in either SQL or the DataFrame/Dataset API.
Spark SQL is broken up into four subprojects:
- Catalyst (sql/catalyst) - An implementation-agnostic framework for manipulating trees of relational operators and expressions.
- Execution (sql/core) - A query planner / execution engine for translating Catalyst's logical query plans into Spark RDDs. This component also includes a new public interface, SQLContext, that allows users to execute SQL or LINQ statements against existing RDDs and Parquet files.
- Hive Support (sql/hive) - Includes an extension of SQLContext called HiveContext that allows users to write queries using a subset of HiveQL and access data from a Hive Metastore using Hive SerDes. There are also wrappers that allows users to run queries that include Hive UDFs, UDAFs, and UDTFs.
- HiveServer and CLI support (sql/hive-thriftserver) - Includes support for the SQL CLI (bin/spark-sql) and a HiveServer2 (for JDBC/ODBC) compatible server.