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The amount of smaller table rows for a match in vector map be a part of hash tables where by we utilize the repeated area optimization in overflow vectorized row batch for be a part of queries employing MapJoin. A price of -one indicates do utilize the join end result optimization. Or else, threshold worth might be 0 to utmost integer.

Produces vital schema with a startup if one particular doesn't exist. Reset this to Phony, soon after making it once.

For conditional joins, if enter stream from a little alias could be instantly applied to the join operator with out filtering or projection, the alias need not be pre-staged in the dispersed cache via a mapred local job. Presently, this isn't dealing with vectorization or Tez execution motor.

When correct, this activates dynamic partition pruning for your Spark motor, to ensure that joins on partition keys are going to be processed by composing to A short lived HDFS file, and read later for getting rid of avoidable partitions.

When genuine, this turns on dynamic partition pruning with the Spark engine, in order that joins on partition keys will likely be processed by creating to a temporary HDFS file, and read later for getting rid of unneeded partitions.

If turned on, splits generated by ORC will contain metadata with regard to the stripes in the file. This information is go through remotely (from your shopper or HiveServer2 equipment) and despatched to many of the responsibilities.

Establish if we receive a skew key in join. If we see a lot more than the required number of rows With read this post here all the identical essential in be a part of operator, we think The crucial element as a skew join important.

List of comma-divided keys transpiring in table Houses that can get inherited to newly produced partitions. * indicates many of the keys will get inherited.

Regardless of whether joins can be mechanically transformed to bucket map joins in Hive when Tez is utilised that site given that the execution engine (hive.execution.motor is ready to "tez").

Although mr stays the default motor for historic factors, it really is by itself a historical engine and is deprecated within the Hive 2 line (HIVE-12300). It might be taken out without the need of more warning.

Determine if we obtain a skew important in sign up for. If we see greater than the desired variety of rows While using the same crucial in be a part of operator, we predict The real key as a skew join important.

When Fake, would not create a lock file and as a consequence the cleardanglingscratchdir Resource are not able to take out any dangling scratch directories.

To scrub up the Hive scratch directory when starting off the Hive server (or HiveServer2). This isn't an selection for a multi-user ecosystem since it will unintentionally eliminate the scratch Listing in use.

Range of consecutive unsuccessful compactions for your provided partition and then the Initiator will end aiming to timetable compactions instantly.