mapred.reduce.tasks
-1
The default number of reduce tasks per job. Typically set
to a prime close to the number of available hosts. Ignored when
mapred.job.tracker is "local". Hadoop set this to 1 by default, whereas hive uses -1 as its default value.
By setting this property to -1, Hive will automatically figure out what should be the number of reducers.
hive.exec.reducers.bytes.per.reducer
1000000000
size per reducer.The default is 1G, i.e if the input size is 10G, it will use 10 reducers.
hive.exec.reducers.max
999
max number of reducers will be used. If the one
specified in the configuration parameter mapred.reduce.tasks is
negative, hive will use this one as the max number of reducers when
automatically determine number of reducers.
hive.cli.print.header
false
Whether to print the names of the columns in query output.
hive.cli.print.current.db
false
Whether to include the current database in the hive prompt.
hive.cli.prompt
hive
Command line prompt configuration value. Other hiveconf can be used in
this configuration value. Variable substitution will only be invoked at the hive
cli startup.
hive.cli.pretty.output.num.cols
-1
The number of columns to use when formatting output generated
by the DESCRIBE PRETTY table_name command. If the value of this property
is -1, then hive will use the auto-detected terminal width.
hive.exec.scratchdir
/tmp/hive-${user.name}
Scratch space for Hive jobs
hive.exec.local.scratchdir
/tmp/${user.name}
Local scratch space for Hive jobs
hive.test.mode
false
whether hive is running in test mode. If yes, it turns on sampling and prefixes the output tablename
hive.test.mode.prefix
test_
if hive is running in test mode, prefixes the output table by this string
hive.test.mode.samplefreq
32
if hive is running in test mode and table is not bucketed, sampling frequency
hive.test.mode.nosamplelist
if hive is running in test mode, dont sample the above comma seperated list of tables
hive.metastore.uris
Thrift uri for the remote metastore. Used by metastore client to connect to remote metastore.
javax.jdo.option.ConnectionURL
jdbc:derby:;databaseName=metastore_db;create=true
JDBC connect string for a JDBC metastore
javax.jdo.option.ConnectionDriverName
org.apache.derby.jdbc.EmbeddedDriver
Driver class name for a JDBC metastore
javax.jdo.PersistenceManagerFactoryClass
org.datanucleus.jdo.JDOPersistenceManagerFactory
class implementing the jdo persistence
javax.jdo.option.DetachAllOnCommit
true
detaches all objects from session so that they can be used after transaction is committed
javax.jdo.option.NonTransactionalRead
true
reads outside of transactions
javax.jdo.option.ConnectionUserName
APP
username to use against metastore database
javax.jdo.option.ConnectionPassword
mine
password to use against metastore database
javax.jdo.option.Multithreaded
true
Set this to true if multiple threads access metastore through JDO concurrently.
datanucleus.connectionPoolingType
DBCP
Uses a DBCP connection pool for JDBC metastore
datanucleus.validateTables
false
validates existing schema against code. turn this on if you want to verify existing schema
datanucleus.validateColumns
false
validates existing schema against code. turn this on if you want to verify existing schema
datanucleus.validateConstraints
false
validates existing schema against code. turn this on if you want to verify existing schema
datanucleus.storeManagerType
rdbms
metadata store type
datanucleus.autoCreateSchema
true
creates necessary schema on a startup if one doesn't exist. set this to false, after creating it once
datanucleus.autoStartMechanismMode
checked
throw exception if metadata tables are incorrect
datanucleus.transactionIsolation
read-committed
Default transaction isolation level for identity generation.
datanucleus.cache.level2
false
Use a level 2 cache. Turn this off if metadata is changed independently of hive metastore server
datanucleus.cache.level2.type
SOFT
SOFT=soft reference based cache, WEAK=weak reference based cache.
datanucleus.identifierFactory
datanucleus
Name of the identifier factory to use when generating table/column names etc. 'datanucleus' is used for backward compatibility
datanucleus.plugin.pluginRegistryBundleCheck
LOG
Defines what happens when plugin bundles are found and are duplicated [EXCEPTION|LOG|NONE]
hive.metastore.warehouse.dir
/user/hive/warehouse
location of default database for the warehouse
hive.metastore.execute.setugi
false
In unsecure mode, setting this property to true will cause the metastore to execute DFS operations using the client's reported user and group permissions. Note that this property must be set on both the client and server sides. Further note that its best effort. If client sets its to true and server sets it to false, client setting will be ignored.
hive.metastore.event.listeners
list of comma seperated listeners for metastore events.
hive.metastore.partition.inherit.table.properties
list of comma seperated keys occurring in table properties which will get inherited to newly created partitions. * implies all the keys will get inherited.
hive.metadata.export.location
When used in conjunction with the org.apache.hadoop.hive.ql.parse.MetaDataExportListener pre event listener, it is the location to which the metadata will be exported. The default is an empty string, which results in the metadata being exported to the current user's home directory on HDFS.
hive.metadata.move.exported.metadata.to.trash
When used in conjunction with the org.apache.hadoop.hive.ql.parse.MetaDataExportListener pre event listener, this setting determines if the metadata that is exported will subsequently be moved to the user's trash directory alongside the dropped table data. This ensures that the metadata will be cleaned up along with the dropped table data.
hive.metastore.partition.name.whitelist.pattern
Partition names will be checked against this regex pattern and rejected if not matched.
hive.metastore.end.function.listeners
list of comma separated listeners for the end of metastore functions.
hive.metastore.event.expiry.duration
0
Duration after which events expire from events table (in seconds)
hive.metastore.event.clean.freq
0
Frequency at which timer task runs to purge expired events in metastore(in seconds).
hive.metastore.connect.retries
5
Number of retries while opening a connection to metastore
hive.metastore.failure.retries
3
Number of retries upon failure of Thrift metastore calls
hive.metastore.client.connect.retry.delay
1
Number of seconds for the client to wait between consecutive connection attempts
hive.metastore.client.socket.timeout
20
MetaStore Client socket timeout in seconds
hive.metastore.rawstore.impl
org.apache.hadoop.hive.metastore.ObjectStore
Name of the class that implements org.apache.hadoop.hive.metastore.rawstore interface. This class is used to store and retrieval of raw metadata objects such as table, database
hive.metastore.batch.retrieve.max
300
Maximum number of objects (tables/partitions) can be retrieved from metastore in one batch. The higher the number, the less the number of round trips is needed to the Hive metastore server, but it may also cause higher memory requirement at the client side.
hive.metastore.batch.retrieve.table.partition.max
1000
Maximum number of table partitions that metastore internally retrieves in one batch.
hive.default.fileformat
TextFile
Default file format for CREATE TABLE statement. Options are TextFile and SequenceFile. Users can explicitly say CREATE TABLE ... STORED AS <TEXTFILE|SEQUENCEFILE> to override
hive.fileformat.check
true
Whether to check file format or not when loading data files
hive.map.aggr
true
Whether to use map-side aggregation in Hive Group By queries
hive.groupby.skewindata
false
Whether there is skew in data to optimize group by queries
hive.optimize.multigroupby.common.distincts
true
Whether to optimize a multi-groupby query with the same distinct.
Consider a query like:
from src
insert overwrite table dest1 select col1, count(distinct colx) group by col1
insert overwrite table dest2 select col2, count(distinct colx) group by col2;
With this parameter set to true, first we spray by the distinct value (colx), and then
perform the 2 groups bys. This makes sense if map-side aggregation is turned off. However,
with maps-side aggregation, it might be useful in some cases to treat the 2 inserts independently,
thereby performing the query above in 2MR jobs instead of 3 (due to spraying by distinct key first).
If this parameter is turned off, we dont consider the fact that the distinct key is the same across
different MR jobs.
hive.groupby.mapaggr.checkinterval
100000
Number of rows after which size of the grouping keys/aggregation classes is performed
hive.mapred.local.mem
0
For local mode, memory of the mappers/reducers
hive.mapjoin.followby.map.aggr.hash.percentmemory
0.3
Portion of total memory to be used by map-side grup aggregation hash table, when this group by is followed by map join
hive.map.aggr.hash.force.flush.memory.threshold
0.9
The max memory to be used by map-side grup aggregation hash table, if the memory usage is higher than this number, force to flush data
hive.map.aggr.hash.percentmemory
0.5
Portion of total memory to be used by map-side grup aggregation hash table
hive.map.aggr.hash.min.reduction
0.5
Hash aggregation will be turned off if the ratio between hash
table size and input rows is bigger than this number. Set to 1 to make sure
hash aggregation is never turned off.
hive.optimize.cp
true
Whether to enable column pruner
hive.optimize.index.filter
false
Whether to enable automatic use of indexes
hive.optimize.index.groupby
false
Whether to enable optimization of group-by queries using Aggregate indexes.
hive.optimize.ppd
true
Whether to enable predicate pushdown
hive.optimize.ppd.storage
true
Whether to push predicates down into storage handlers. Ignored when hive.optimize.ppd is false.
hive.ppd.recognizetransivity
true
Whether to transitively replicate predicate filters over equijoin conditions.
hive.optimize.groupby
true
Whether to enable the bucketed group by from bucketed partitions/tables.
hive.optimize.skewjoin.compiletime
false
Whether to create a separate plan for skewed keys for the tables in the join.
This is based on the skewed keys stored in the metadata. At compile time, the plan is broken
into different joins: one for the skewed keys, and the other for the remaining keys. And then,
a union is performed for the 2 joins generated above. So unless the same skewed key is present
in both the joined tables, the join for the skewed key will be performed as a map-side join.
The main difference between this paramater and hive.optimize.skewjoin is that this parameter
uses the skew information stored in the metastore to optimize the plan at compile time itself.
If there is no skew information in the metadata, this parameter will not have any affect.
Both hive.optimize.skewjoin.compiletime and hive.optimize.skewjoin should be set to true.
Ideally, hive.optimize.skewjoin should be renamed as hive.optimize.skewjoin.runtime, but not doing
so for backward compatibility.
If the skew information is correctly stored in the metadata, hive.optimize.skewjoin.compiletime
would change the query plan to take care of it, and hive.optimize.skewjoin will be a no-op.
hive.optimize.union.remove
false
Whether to remove the union and push the operators between union and the filesink above
union. This avoids an extra scan of the output by union. This is independently useful for union
queries, and specially useful when hive.optimize.skewjoin.compiletime is set to true, since an
extra union is inserted.
The merge is triggered if either of hive.merge.mapfiles or hive.merge.mapredfiles is set to true.
If the user has set hive.merge.mapfiles to true and hive.merge.mapredfiles to false, the idea was the
number of reducers are few, so the number of files anyway are small. However, with this optimization,
we are increasing the number of files possibly by a big margin. So, we merge aggresively.
hive.mapred.supports.subdirectories
false
Whether the version of hadoop which is running supports sub-directories for tables/partitions.
Many hive optimizations can be applied if the hadoop version supports sub-directories for
tables/partitions. It was added by MAPREDUCE-1501
hive.multigroupby.singlemr
false
Whether to optimize multi group by query to generate single M/R
job plan. If the multi group by query has common group by keys, it will be
optimized to generate single M/R job.
hive.map.groupby.sorted
false
If the bucketing/sorting properties of the table exactly match the grouping key, whether to
perform the group by in the mapper by using BucketizedHiveInputFormat. The only downside to this
is that it limits the number of mappers to the number of files.
hive.map.groupby.sorted.testmode
false
If the bucketing/sorting properties of the table exactly match the grouping key, whether to
perform the group by in the mapper by using BucketizedHiveInputFormat. If the test mode is set, the plan
is not converted, but a query property is set to denote the same.
hive.new.job.grouping.set.cardinality
30
Whether a new map-reduce job should be launched for grouping sets/rollups/cubes.
For a query like: select a, b, c, count(1) from T group by a, b, c with rollup;
4 rows are created per row: (a, b, c), (a, b, null), (a, null, null), (null, null, null).
This can lead to explosion across map-reduce boundary if the cardinality of T is very high,
and map-side aggregation does not do a very good job.
This parameter decides if hive should add an additional map-reduce job. If the grouping set
cardinality (4 in the example above), is more than this value, a new MR job is added under the
assumption that the orginal group by will reduce the data size.
hive.join.emit.interval
1000
How many rows in the right-most join operand Hive should buffer before emitting the join result.
hive.join.cache.size
25000
How many rows in the joining tables (except the streaming table) should be cached in memory.
hive.mapjoin.bucket.cache.size
100
How many values in each keys in the map-joined table should be cached in memory.
hive.mapjoin.cache.numrows
25000
How many rows should be cached by jdbm for map join.
hive.optimize.skewjoin
false
Whether to enable skew join optimization.
The algorithm is as follows: At runtime, detect the keys with a large skew. Instead of
processing those keys, store them temporarily in a hdfs directory. In a follow-up map-reduce
job, process those skewed keys. The same key need not be skewed for all the tables, and so,
the follow-up map-reduce job (for the skewed keys) would be much faster, since it would be a
map-join.
hive.skewjoin.key
100000
Determine if we get a skew key in join. If we see more
than the specified number of rows with the same key in join operator,
we think the key as a skew join key.
hive.skewjoin.mapjoin.map.tasks
10000
Determine the number of map task used in the follow up map join job
for a skew join. It should be used together with hive.skewjoin.mapjoin.min.split
to perform a fine grained control.
hive.skewjoin.mapjoin.min.split
33554432
Determine the number of map task at most used in the follow up map join job
for a skew join by specifying the minimum split size. It should be used together with
hive.skewjoin.mapjoin.map.tasks to perform a fine grained control.
hive.mapred.mode
nonstrict
The mode in which the hive operations are being performed.
In strict mode, some risky queries are not allowed to run. They include:
Cartesian Product.
No partition being picked up for a query.
Comparing bigints and strings.
Comparing bigints and doubles.
Orderby without limit.
hive.enforce.bucketmapjoin
false
If the user asked for bucketed map-side join, and it cannot be performed,
should the query fail or not ? For eg, if the buckets in the tables being joined are
not a multiple of each other, bucketed map-side join cannot be performed, and the
query will fail if hive.enforce.bucketmapjoin is set to true.
hive.exec.script.maxerrsize
100000
Maximum number of bytes a script is allowed to emit to standard error (per map-reduce task). This prevents runaway scripts from filling logs partitions to capacity
hive.exec.script.allow.partial.consumption
false
When enabled, this option allows a user script to exit successfully without consuming all the data from the standard input.
hive.script.operator.id.env.var
HIVE_SCRIPT_OPERATOR_ID
Name of the environment variable that holds the unique script operator ID in the user's transform function (the custom mapper/reducer that the user has specified in the query)
hive.script.operator.truncate.env
false
Truncate each environment variable for external script in scripts operator to 20KB (to fit system limits)
hive.exec.compress.output
false
This controls whether the final outputs of a query (to a local/hdfs file or a hive table) is compressed. The compression codec and other options are determined from hadoop config variables mapred.output.compress*
hive.exec.compress.intermediate
false
This controls whether intermediate files produced by hive between multiple map-reduce jobs are compressed. The compression codec and other options are determined from hadoop config variables mapred.output.compress*
hive.exec.parallel
false
Whether to execute jobs in parallel
hive.exec.parallel.thread.number
8
How many jobs at most can be executed in parallel
hive.exec.rowoffset
false
Whether to provide the row offset virtual column
hive.task.progress
false
Whether Hive should periodically update task progress counters during execution. Enabling this allows task progress to be monitored more closely in the job tracker, but may impose a performance penalty. This flag is automatically set to true for jobs with hive.exec.dynamic.partition set to true.
hive.hwi.war.file
lib/hive-hwi-0.11.0.war
This sets the path to the HWI war file, relative to ${HIVE_HOME}.
hive.hwi.listen.host
0.0.0.0
This is the host address the Hive Web Interface will listen on
hive.hwi.listen.port
9999
This is the port the Hive Web Interface will listen on
hive.exec.pre.hooks
Comma-separated list of pre-execution hooks to be invoked for each statement. A pre-execution hook is specified as the name of a Java class which implements the org.apache.hadoop.hive.ql.hooks.ExecuteWithHookContext interface.
hive.exec.post.hooks
Comma-separated list of post-execution hooks to be invoked for each statement. A post-execution hook is specified as the name of a Java class which implements the org.apache.hadoop.hive.ql.hooks.ExecuteWithHookContext interface.
hive.exec.failure.hooks
Comma-separated list of on-failure hooks to be invoked for each statement. An on-failure hook is specified as the name of Java class which implements the org.apache.hadoop.hive.ql.hooks.ExecuteWithHookContext interface.
hive.metastore.init.hooks
A comma separated list of hooks to be invoked at the beginning of HMSHandler initialization. Aninit hook is specified as the name of Java class which extends org.apache.hadoop.hive.metastore.MetaStoreInitListener.
hive.client.stats.publishers
Comma-separated list of statistics publishers to be invoked on counters on each job. A client stats publisher is specified as the name of a Java class which implements the org.apache.hadoop.hive.ql.stats.ClientStatsPublisher interface.
hive.client.stats.counters
Subset of counters that should be of interest for hive.client.stats.publishers (when one wants to limit their publishing). Non-display names should be used
hive.merge.mapfiles
true
Merge small files at the end of a map-only job
hive.merge.mapredfiles
false
Merge small files at the end of a map-reduce job
hive.heartbeat.interval
1000
Send a heartbeat after this interval - used by mapjoin and filter operators
hive.merge.size.per.task
256000000
Size of merged files at the end of the job
hive.merge.smallfiles.avgsize
16000000
When the average output file size of a job is less than this number, Hive will start an additional map-reduce job to merge the output files into bigger files. This is only done for map-only jobs if hive.merge.mapfiles is true, and for map-reduce jobs if hive.merge.mapredfiles is true.
hive.mapjoin.smalltable.filesize
25000000
The threshold for the input file size of the small tables; if the file size is smaller than this threshold, it will try to convert the common join into map join
hive.ignore.mapjoin.hint
true
Ignore the mapjoin hint
hive.mapjoin.localtask.max.memory.usage
0.90
This number means how much memory the local task can take to hold the key/value into in-memory hash table; If the local task's memory usage is more than this number, the local task will be abort by themself. It means the data of small table is too large to be hold in the memory.
hive.mapjoin.followby.gby.localtask.max.memory.usage
0.55
This number means how much memory the local task can take to hold the key/value into in-memory hash table when this map join followed by a group by; If the local task's memory usage is more than this number, the local task will be abort by themself. It means the data of small table is too large to be hold in the memory.
hive.mapjoin.check.memory.rows
100000
The number means after how many rows processed it needs to check the memory usage
hive.auto.convert.join
false
Whether Hive enable the optimization about converting common join into mapjoin based on the input file size
hive.auto.convert.join.noconditionaltask
true
Whether Hive enable the optimization about converting common join into mapjoin based on the input file
size. If this paramater is on, and the sum of size for n-1 of the tables/partitions for a n-way join is smaller than the
specified size, the join is directly converted to a mapjoin (there is no conditional task).
hive.auto.convert.join.noconditionaltask.size
10000000
If hive.auto.convert.join.noconditionaltask is off, this parameter does not take affect. However, if it
is on, and the sum of size for n-1 of the tables/partitions for a n-way join is smaller than this size, the join is directly
converted to a mapjoin(there is no conditional task). The default is 10MB
hive.optimize.mapjoin.mapreduce
false
If hive.auto.convert.join is off, this parameter does not take
affect. If it is on, and if there are map-join jobs followed by a map-reduce
job (for e.g a group by), each map-only job is merged with the following
map-reduce job.
hive.script.auto.progress
false
Whether Hive Tranform/Map/Reduce Clause should automatically send progress information to TaskTracker to avoid the task getting killed because of inactivity. Hive sends progress information when the script is outputting to stderr. This option removes the need of periodically producing stderr messages, but users should be cautious because this may prevent infinite loops in the scripts to be killed by TaskTracker.
hive.script.serde
org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe
The default serde for trasmitting input data to and reading output data from the user scripts.
hive.binary.record.max.length
1000
Read from a binary stream and treat each hive.binary.record.max.length bytes as a record.
The last record before the end of stream can have less than hive.binary.record.max.length bytes
hive.script.recordreader
org.apache.hadoop.hive.ql.exec.TextRecordReader
The default record reader for reading data from the user scripts.
hive.script.recordwriter
org.apache.hadoop.hive.ql.exec.TextRecordWriter
The default record writer for writing data to the user scripts.
hive.input.format
org.apache.hadoop.hive.ql.io.CombineHiveInputFormat
The default input format. Set this to HiveInputFormat if you encounter problems with CombineHiveInputFormat.
hive.udtf.auto.progress
false
Whether Hive should automatically send progress information to TaskTracker when using UDTF's to prevent the task getting killed because of inactivity. Users should be cautious because this may prevent TaskTracker from killing tasks with infinte loops.
hive.mapred.reduce.tasks.speculative.execution
true
Whether speculative execution for reducers should be turned on.
hive.exec.counters.pull.interval
1000
The interval with which to poll the JobTracker for the counters the running job. The smaller it is the more load there will be on the jobtracker, the higher it is the less granular the caught will be.
hive.querylog.location
/tmp/${user.name}
Location of Hive run time structured log file
hive.querylog.enable.plan.progress
true
Whether to log the plan's progress every time a job's progress is checked.
These logs are written to the location specified by hive.querylog.location
hive.querylog.plan.progress.interval
60000
The interval to wait between logging the plan's progress in milliseconds.
If there is a whole number percentage change in the progress of the mappers or the reducers,
the progress is logged regardless of this value.
The actual interval will be the ceiling of (this value divided by the value of
hive.exec.counters.pull.interval) multiplied by the value of hive.exec.counters.pull.interval
I.e. if it is not divide evenly by the value of hive.exec.counters.pull.interval it will be
logged less frequently than specified.
This only has an effect if hive.querylog.enable.plan.progress is set to true.
hive.enforce.bucketing
false
Whether bucketing is enforced. If true, while inserting into the table, bucketing is enforced.
hive.enforce.sorting
false
Whether sorting is enforced. If true, while inserting into the table, sorting is enforced.
hive.optimize.bucketingsorting
true
If hive.enforce.bucketing or hive.enforce.sorting is true, dont create a reducer for enforcing
bucketing/sorting for queries of the form:
insert overwrite table T2 select * from T1;
where T1 and T2 are bucketed/sorted by the same keys into the same number of buckets.
hive.enforce.sortmergebucketmapjoin
false
If the user asked for sort-merge bucketed map-side join, and it cannot be performed,
should the query fail or not ?
hive.auto.convert.sortmerge.join
false
Will the join be automatically converted to a sort-merge join, if the joined tables pass
the criteria for sort-merge join.
hive.auto.convert.sortmerge.join.bigtable.selection.policy
org.apache.hadoop.hive.ql.optimizer.AvgPartitionSizeBasedBigTableSelectorForAutoSMJ
The policy to choose the big table for automatic conversion to sort-merge join.
By default, the table with the largest partitions is assigned the big table. All policies are:
. based on position of the table - the leftmost table is selected
org.apache.hadoop.hive.ql.optimizer.LeftmostBigTableSMJ.
. based on total size (all the partitions selected in the query) of the table
org.apache.hadoop.hive.ql.optimizer.TableSizeBasedBigTableSelectorForAutoSMJ.
. based on average size (all the partitions selected in the query) of the table
org.apache.hadoop.hive.ql.optimizer.AvgPartitionSizeBasedBigTableSelectorForAutoSMJ.
New policies can be added in future.
hive.metastore.ds.connection.url.hook
Name of the hook to use for retriving the JDO connection URL. If empty, the value in javax.jdo.option.ConnectionURL is used
hive.metastore.ds.retry.attempts
1
The number of times to retry a metastore call if there were a connection error
hive.metastore.ds.retry.interval
1000
The number of miliseconds between metastore retry attempts
hive.metastore.server.min.threads
200
Minimum number of worker threads in the Thrift server's pool.
hive.metastore.server.max.threads
100000
Maximum number of worker threads in the Thrift server's pool.
hive.metastore.server.tcp.keepalive
true
Whether to enable TCP keepalive for the metastore server. Keepalive will prevent accumulation of half-open connections.
hive.metastore.sasl.enabled
false
If true, the metastore thrift interface will be secured with SASL. Clients must authenticate with Kerberos.
hive.metastore.thrift.framed.transport.enabled
false
If true, the metastore thrift interface will use TFramedTransport. When false (default) a standard TTransport is used.
hive.metastore.kerberos.keytab.file
The path to the Kerberos Keytab file containing the metastore thrift server's service principal.
hive.metastore.kerberos.principal
hive-metastore/_HOST@EXAMPLE.COM
The service principal for the metastore thrift server. The special string _HOST will be replaced automatically with the correct host name.
hive.cluster.delegation.token.store.class
org.apache.hadoop.hive.thrift.MemoryTokenStore
The delegation token store implementation. Set to org.apache.hadoop.hive.thrift.ZooKeeperTokenStore for load-balanced cluster.
hive.cluster.delegation.token.store.zookeeper.connectString
localhost:2181
The ZooKeeper token store connect string.
hive.cluster.delegation.token.store.zookeeper.znode
/hive/cluster/delegation
The root path for token store data.
hive.cluster.delegation.token.store.zookeeper.acl
sasl:hive/host1@EXAMPLE.COM:cdrwa,sasl:hive/host2@EXAMPLE.COM:cdrwa
ACL for token store entries. List comma separated all server principals for the cluster.
hive.metastore.cache.pinobjtypes
Table,StorageDescriptor,SerDeInfo,Partition,Database,Type,FieldSchema,Order
List of comma separated metastore object types that should be pinned in the cache
hive.optimize.reducededuplication
true
Remove extra map-reduce jobs if the data is already clustered by the same key which needs to be used again. This should always be set to true. Since it is a new feature, it has been made configurable.
hive.optimize.reducededuplication.min.reducer
4
Reduce deduplication merges two RSs by moving key/parts/reducer-num of the child RS to parent RS.
That means if reducer-num of the child RS is fixed (order by or forced bucketing) and small, it can make very slow, single MR.
The optimization will be disabled if number of reducers is less than specified value.
hive.exec.dynamic.partition
true
Whether or not to allow dynamic partitions in DML/DDL.
hive.exec.dynamic.partition.mode
strict
In strict mode, the user must specify at least one static partition in case the user accidentally overwrites all partitions.
hive.exec.max.dynamic.partitions
1000
Maximum number of dynamic partitions allowed to be created in total.
hive.exec.max.dynamic.partitions.pernode
100
Maximum number of dynamic partitions allowed to be created in each mapper/reducer node.
hive.exec.max.created.files
100000
Maximum number of HDFS files created by all mappers/reducers in a MapReduce job.
hive.exec.default.partition.name
__HIVE_DEFAULT_PARTITION__
The default partition name in case the dynamic partition column value is null/empty string or anyother values that cannot be escaped. This value must not contain any special character used in HDFS URI (e.g., ':', '%', '/' etc). The user has to be aware that the dynamic partition value should not contain this value to avoid confusions.
hive.stats.dbclass
jdbc:derby
The default database that stores temporary hive statistics.
hive.stats.autogather
true
A flag to gather statistics automatically during the INSERT OVERWRITE command.
hive.stats.jdbcdriver
org.apache.derby.jdbc.EmbeddedDriver
The JDBC driver for the database that stores temporary hive statistics.
hive.stats.dbconnectionstring
jdbc:derby:;databaseName=TempStatsStore;create=true
The default connection string for the database that stores temporary hive statistics.
hive.stats.default.publisher
The Java class (implementing the StatsPublisher interface) that is used by default if hive.stats.dbclass is not JDBC or HBase.
hive.stats.default.aggregator
The Java class (implementing the StatsAggregator interface) that is used by default if hive.stats.dbclass is not JDBC or HBase.
hive.stats.jdbc.timeout
30
Timeout value (number of seconds) used by JDBC connection and statements.
hive.stats.retries.max
0
Maximum number of retries when stats publisher/aggregator got an exception updating intermediate database. Default is no tries on failures.
hive.stats.retries.wait
3000
The base waiting window (in milliseconds) before the next retry. The actual wait time is calculated by baseWindow * failues baseWindow * (failure 1) * (random number between [0.0,1.0]).
hive.stats.reliable
false
Whether queries will fail because stats cannot be collected completely accurately.
If this is set to true, reading/writing from/into a partition may fail becuase the stats
could not be computed accurately.
hive.stats.collect.tablekeys
false
Whether join and group by keys on tables are derived and maintained in the QueryPlan.
This is useful to identify how tables are accessed and to determine if they should be bucketed.
hive.stats.collect.scancols
false
Whether column accesses are tracked in the QueryPlan.
This is useful to identify how tables are accessed and to determine if there are wasted columns that can be trimmed.
hive.stats.ndv.error
20.0
Standard error expressed in percentage. Provides a tradeoff between accuracy and compute cost.A lower value for error indicates higher accuracy and a higher compute cost.
hive.stats.key.prefix.max.length
200
Determines if when the prefix of the key used for intermediate stats collection
exceeds a certain length, a hash of the key is used instead. If the value < 0 then hashing
is never used, if the value >= 0 then hashing is used only when the key prefixes length
exceeds that value. The key prefix is defined as everything preceding the task ID in the key.
hive.support.concurrency
false
Whether hive supports concurrency or not. A zookeeper instance must be up and running for the default hive lock manager to support read-write locks.
hive.lock.numretries
100
The number of times you want to try to get all the locks
hive.unlock.numretries
10
The number of times you want to retry to do one unlock
hive.lock.sleep.between.retries
60
The sleep time (in seconds) between various retries
hive.zookeeper.quorum
The list of zookeeper servers to talk to. This is only needed for read/write locks.
hive.zookeeper.client.port
2181
The port of zookeeper servers to talk to. This is only needed for read/write locks.
hive.zookeeper.session.timeout
600000
Zookeeper client's session timeout. The client is disconnected, and as a result, all locks released, if a heartbeat is not sent in the timeout.
hive.zookeeper.namespace
hive_zookeeper_namespace
The parent node under which all zookeeper nodes are created.
hive.zookeeper.clean.extra.nodes
false
Clean extra nodes at the end of the session.
fs.har.impl
org.apache.hadoop.hive.shims.HiveHarFileSystem
The implementation for accessing Hadoop Archives. Note that this won't be applicable to Hadoop vers less than 0.20
hive.archive.enabled
false
Whether archiving operations are permitted
hive.fetch.output.serde
org.apache.hadoop.hive.serde2.DelimitedJSONSerDe
The serde used by FetchTask to serialize the fetch output.
hive.exec.mode.local.auto
false
Let hive determine whether to run in local mode automatically
hive.exec.drop.ignorenonexistent
true
Do not report an error if DROP TABLE/VIEW specifies a non-existent table/view
hive.exec.show.job.failure.debug.info
true
If a job fails, whether to provide a link in the CLI to the task with the
most failures, along with debugging hints if applicable.
hive.auto.progress.timeout
0
How long to run autoprogressor for the script/UDTF operators (in seconds).
Set to 0 for forever.
hive.hbase.wal.enabled
true
Whether writes to HBase should be forced to the write-ahead log. Disabling this improves HBase write performance at the risk of lost writes in case of a crash.
hive.table.parameters.default
Default property values for newly created tables
hive.entity.separator
@
Separator used to construct names of tables and partitions. For example, dbname@tablename@partitionname
hive.ddl.createtablelike.properties.whitelist
Table Properties to copy over when executing a Create Table Like.
hive.variable.substitute
true
This enables substitution using syntax like ${var} ${system:var} and ${env:var}.
hive.variable.substitute.depth
40
The maximum replacements the substitution engine will do.
hive.conf.validation
true
Eables type checking for registered hive configurations
hive.security.authorization.enabled
false
enable or disable the hive client authorization
hive.security.authorization.manager
org.apache.hadoop.hive.ql.security.authorization.DefaultHiveAuthorizationProvider
the hive client authorization manager class name.
The user defined authorization class should implement interface org.apache.hadoop.hive.ql.security.authorization.HiveAuthorizationProvider.
hive.security.metastore.authorization.manager
org.apache.hadoop.hive.ql.security.authorization.DefaultHiveMetastoreAuthorizationProvider
authorization manager class name to be used in the metastore for authorization.
The user defined authorization class should implement interface org.apache.hadoop.hive.ql.security.authorization.HiveMetastoreAuthorizationProvider.
hive.security.authenticator.manager
org.apache.hadoop.hive.ql.security.HadoopDefaultAuthenticator
hive client authenticator manager class name.
The user defined authenticator should implement interface org.apache.hadoop.hive.ql.security.HiveAuthenticationProvider.
hive.security.metastore.authenticator.manager
org.apache.hadoop.hive.ql.security.HadoopDefaultMetastoreAuthenticator
authenticator manager class name to be used in the metastore for authentication.
The user defined authenticator should implement interface org.apache.hadoop.hive.ql.security.HiveAuthenticationProvider.
hive.security.authorization.createtable.user.grants
the privileges automatically granted to some users whenever a table gets created.
An example like "userX,userY:select;userZ:create" will grant select privilege to userX and userY,
and grant create privilege to userZ whenever a new table created.
hive.security.authorization.createtable.group.grants
the privileges automatically granted to some groups whenever a table gets created.
An example like "groupX,groupY:select;groupZ:create" will grant select privilege to groupX and groupY,
and grant create privilege to groupZ whenever a new table created.
hive.security.authorization.createtable.role.grants
the privileges automatically granted to some roles whenever a table gets created.
An example like "roleX,roleY:select;roleZ:create" will grant select privilege to roleX and roleY,
and grant create privilege to roleZ whenever a new table created.
hive.security.authorization.createtable.owner.grants
the privileges automatically granted to the owner whenever a table gets created.
An example like "select,drop" will grant select and drop privilege to the owner of the table
hive.metastore.authorization.storage.checks
false
Should the metastore do authorization checks against the underlying storage
for operations like drop-partition (disallow the drop-partition if the user in
question doesn't have permissions to delete the corresponding directory
on the storage).
hive.error.on.empty.partition
false
Whether to throw an excpetion if dynamic partition insert generates empty results.
hive.index.compact.file.ignore.hdfs
false
True the hdfs location stored in the index file will be igbored at runtime.
If the data got moved or the name of the cluster got changed, the index data should still be usable.
hive.optimize.index.filter.compact.minsize
5368709120
Minimum size (in bytes) of the inputs on which a compact index is automatically used.
hive.optimize.index.filter.compact.maxsize
-1
Maximum size (in bytes) of the inputs on which a compact index is automatically used.
A negative number is equivalent to infinity.
hive.index.compact.query.max.size
10737418240
The maximum number of bytes that a query using the compact index can read. Negative value is equivalent to infinity.
hive.index.compact.query.max.entries
10000000
The maximum number of index entries to read during a query that uses the compact index. Negative value is equivalent to infinity.
hive.index.compact.binary.search
true
Whether or not to use a binary search to find the entries in an index table that match the filter, where possible
hive.exim.uri.scheme.whitelist
hdfs,pfile
A comma separated list of acceptable URI schemes for import and export.
hive.lock.mapred.only.operation
false
This param is to control whether or not only do lock on queries
that need to execute at least one mapred job.
hive.limit.row.max.size
100000
When trying a smaller subset of data for simple LIMIT, how much size we need to guarantee
each row to have at least.
hive.limit.optimize.limit.file
10
When trying a smaller subset of data for simple LIMIT, maximum number of files we can
sample.
hive.limit.optimize.enable
false
Whether to enable to optimization to trying a smaller subset of data for simple LIMIT first.
hive.limit.optimize.fetch.max
50000
Maximum number of rows allowed for a smaller subset of data for simple LIMIT, if it is a fetch query.
Insert queries are not restricted by this limit.
hive.rework.mapredwork
false
should rework the mapred work or not.
This is first introduced by SymlinkTextInputFormat to replace symlink files with real paths at compile time.
hive.exec.concatenate.check.index
true
If this sets to true, hive will throw error when doing
'alter table tbl_name [partSpec] concatenate' on a table/partition
that has indexes on it. The reason the user want to set this to true
is because it can help user to avoid handling all index drop, recreation,
rebuild work. This is very helpful for tables with thousands of partitions.
hive.sample.seednumber
0
A number used to percentage sampling. By changing this number, user will change the subsets
of data sampled.
hive.io.exception.handlers
A list of io exception handler class names. This is used
to construct a list exception handlers to handle exceptions thrown
by record readers
hive.autogen.columnalias.prefix.label
_c
String used as a prefix when auto generating column alias.
By default the prefix label will be appended with a column position number to form the column alias. Auto generation would happen if an aggregate function is used in a select clause without an explicit alias.
hive.autogen.columnalias.prefix.includefuncname
false
Whether to include function name in the column alias auto generated by hive.
hive.exec.perf.logger
org.apache.hadoop.hive.ql.log.PerfLogger
The class responsible logging client side performance metrics. Must be a subclass of org.apache.hadoop.hive.ql.log.PerfLogger
hive.start.cleanup.scratchdir
false
To cleanup the hive scratchdir while starting the hive server
hive.output.file.extension
String used as a file extension for output files. If not set, defaults to the codec extension for text files (e.g. ".gz"), or no extension otherwise.
hive.insert.into.multilevel.dirs
false
Where to insert into multilevel directories like
"insert directory '/HIVEFT25686/chinna/' from table"
hive.warehouse.subdir.inherit.perms
false
Set this to true if the the table directories should inherit the
permission of the warehouse or database directory instead of being created
with the permissions derived from dfs umask
hive.exec.job.debug.capture.stacktraces
true
Whether or not stack traces parsed from the task logs of a sampled failed task for
each failed job should be stored in the SessionState
hive.exec.driver.run.hooks
A comma separated list of hooks which implement HiveDriverRunHook and will be run at the
beginning and end of Driver.run, these will be run in the order specified
hive.ddl.output.format
text
The data format to use for DDL output. One of "text" (for human
readable text) or "json" (for a json object).
hive.transform.escape.input
false
This adds an option to escape special chars (newlines, carriage returns and
tabs) when they are passed to the user script. This is useful if the hive tables
can contain data that contains special characters.
hive.exec.rcfile.use.explicit.header
true
If this is set the header for RC Files will simply be RCF. If this is not
set the header will be that borrowed from sequence files, e.g. SEQ- followed
by the input and output RC File formats.
hive.multi.insert.move.tasks.share.dependencies
false
If this is set all move tasks for tables/partitions (not directories) at the end of a
multi-insert query will only begin once the dependencies for all these move tasks have been
met.
Advantages: If concurrency is enabled, the locks will only be released once the query has
finished, so with this config enabled, the time when the table/partition is
generated will be much closer to when the lock on it is released.
Disadvantages: If concurrency is not enabled, with this disabled, the tables/partitions which
are produced by this query and finish earlier will be available for querying
much earlier. Since the locks are only released once the query finishes, this
does not apply if concurrency is enabled.
hive.fetch.task.conversion
minimal
Some select queries can be converted to single FETCH task minimizing latency.
Currently the query should be single sourced not having any subquery and should not have
any aggregations or distincts (which incurrs RS), lateral views and joins.
1. minimal : SELECT STAR, FILTER on partition columns, LIMIT only
2. more : SELECT, FILTER, LIMIT only (TABLESAMPLE, virtual columns)
hive.hmshandler.retry.attempts
1
The number of times to retry a HMSHandler call if there were a connection error
hive.hmshandler.retry.interval
1000
The number of miliseconds between HMSHandler retry attempts
hive.server.read.socket.timeout
10
Timeout for the HiveServer to close the connection if no response from the client in N seconds, defaults to 10 seconds.
hive.server.tcp.keepalive
true
Whether to enable TCP keepalive for the Hive server. Keepalive will prevent accumulation of half-open connections.
hive.decode.partition.name
false
Whether to show the unquoted partition names in query results.
hive.log4j.file
Hive log4j configuration file.
If the property is not set, then logging will be initialized using hive-log4j.properties found on the classpath.
If the property is set, the value must be a valid URI (java.net.URI, e.g. "file:///tmp/my-logging.properties"), which you can then extract a URL from and pass to PropertyConfigurator.configure(URL).
hive.exec.log4j.file
Hive log4j configuration file for execution mode(sub command).
If the property is not set, then logging will be initialized using hive-exec-log4j.properties found on the classpath.
If the property is set, the value must be a valid URI (java.net.URI, e.g. "file:///tmp/my-logging.properties"), which you can then extract a URL from and pass to PropertyConfigurator.configure(URL).
hive.exec.infer.bucket.sort
false
If this is set, when writing partitions, the metadata will include the bucketing/sorting
properties with which the data was written if any (this will not overwrite the metadata
inherited from the table if the table is bucketed/sorted)
hive.exec.infer.bucket.sort.num.buckets.power.two
false
If this is set, when setting the number of reducers for the map reduce task which writes the
final output files, it will choose a number which is a power of two, unless the user specifies
the number of reducers to use using mapred.reduce.tasks. The number of reducers
may be set to a power of two, only to be followed by a merge task meaning preventing
anything from being inferred.
With hive.exec.infer.bucket.sort set to true:
Advantages: If this is not set, the number of buckets for partitions will seem arbitrary,
which means that the number of mappers used for optimized joins, for example, will
be very low. With this set, since the number of buckets used for any partition is
a power of two, the number of mappers used for optimized joins will be the least
number of buckets used by any partition being joined.
Disadvantages: This may mean a much larger or much smaller number of reducers being used in the
final map reduce job, e.g. if a job was originally going to take 257 reducers,
it will now take 512 reducers, similarly if the max number of reducers is 511,
and a job was going to use this many, it will now use 256 reducers.
hive.groupby.orderby.position.alias
false
Whether to enable using Column Position Alias in Group By or Order By
hive.server2.thrift.min.worker.threads
5
Minimum number of Thrift worker threads
hive.server2.thrift.max.worker.threads
100
Maximum number of Thrift worker threads
hive.server2.thrift.port
10000
Port number of HiveServer2 Thrift interface.
Can be overridden by setting $HIVE_SERVER2_THRIFT_PORT
hive.server2.thrift.bind.host
localhost
Bind host on which to run the HiveServer2 Thrift interface.
Can be overridden by setting $HIVE_SERVER2_THRIFT_BIND_HOST
hive.server2.authentication
NONE
Client authentication types.
NONE: no authentication check
LDAP: LDAP/AD based authentication
KERBEROS: Kerberos/GSSAPI authentication
CUSTOM: Custom authentication provider
(Use with property hive.server2.custom.authentication.class)
hive.server2.custom.authentication.class
Custom authentication class. Used when property
'hive.server2.authentication' is set to 'CUSTOM'. Provided class
must be a proper implementation of the interface
org.apache.hive.service.auth.PasswdAuthenticationProvider. HiveServer2
will call its Authenticate(user, passed) method to authenticate requests.
The implementation may optionally extend the Hadoop's
org.apache.hadoop.conf.Configured class to grab Hive's Configuration object.
>hive.server2.authentication.kerberos.principal
Kerberos server principal
>hive.server2.authentication.kerberos.keytab
Kerberos keytab file for server principal
hive.server2.authentication.ldap.url
LDAP connection URL
hive.server2.authentication.ldap.baseDN
LDAP base DN
hive.server2.enable.doAs
true
Setting this property to true will have hive server2 execute
hive operations as the user making the calls to it.