Hive Configuration Problems¶
The error message "java.lang.OutOfMemoryError: Java heap space." is displayed during Hive SQL execution.
Solution:
For MapReduce tasks, increase the values of the following parameters:
set mapreduce.map.memory.mb=8192;
set mapreduce.map.java.opts=-Xmx6554M;
set mapreduce.reduce.memory.mb=8192;
set mapreduce.reduce.java.opts=-Xmx6554M;
For Tez tasks, increase the value of the following parameter:
set hive.tez.container.size=8192;
After a column name is changed to a new one using the Hive SQL as statement, the error message "Invalid table alias or column reference 'xxx'." is displayed when the original column name is used for compilation.
Solution: Run the set hive.cbo.enable=true; statement.
The error message "Unsupported SubQuery Expression 'xxx': Only SubQuery expressions that are top level conjuncts are allowed." is displayed during Hive SQL subquery compilation.
Solution: Run the set hive.cbo.enable=true; statement.
The error message "CalciteSubquerySemanticException [Error 10249]: Unsupported SubQuery Expression Currently SubQuery expressions are only allowed as Where and Having Clause predicates." is displayed during Hive SQL subquery compilation.
Solution: Run the set hive.cbo.enable=true; statement.
The error message "Error running query: java.lang.AssertionError: Cannot add expression of different type to set." is displayed during Hive SQL compilation.
Solution: Run the set hive.cbo.enable=false; statement.
The error message "java.lang.NullPointerException at org.apache.hadoop.hive.ql.udf.generic.GenericUDAFComputeStats$GenericUDAFNumericStatsEvaluator.init." is displayed during Hive SQL execution.
Solution: Run the set hive.map.aggr=false; statement.
When hive.auto.convert.join is set to true (enabled by default) and hive.optimize.skewjoin is set to true, the error message "ClassCastException org.apache.hadoop.hive.ql.plan.ConditionalWork cannot be cast to org.apache.hadoop.hive.ql.plan.MapredWork" is displayed.
Solution: Run the set hive.optimize.skewjoin=false; statement.
When hive.auto.convert.join is set to true (enabled by default), hive.optimize.skewjoin is set to true, and hive.exec.parallel is set to true, the error message "java.io.FileNotFoundException: File does not exist:xxx/reduce.xml" is displayed.
Solution:
Method 1: Switch the execution engine to Tez. For details, see Switching the Hive Execution Engine to Tez.
Method 2: Run the set hive.exec.parallel=false; statement.
Method 3: Run the set hive.auto.convert.join=false; statement.