-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.
1000000000
Size per reducer. The default is 1G, i.e if the input size is 10G, it will use 10 reducers.
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.
/tmp/hive-${user.name
}
Scratch space for Hive jobs.
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.
true
Whether to check file format or not when loading data files.
true
Whether to use map-side aggregation in Hive Group By queries.
false
Whether there is skew in data to optimize group by queries.
100000
Number of rows after which size of the grouping keys/aggregation classes is performed.
0
For local mode, memory of the mappers/reducers.
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.
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.
0.5
Portion of total memory to be used by map-side grup aggregation hash table.
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.
true
Whether to enable the bucketed group by from bucketed partitions/tables.
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.
true
Whether to enable column pruner.
false
Whether to enable automatic use of indexes.
false
Whether to enable optimization of group-by queries using Aggregate indexes.
true
Whether to enable predicate pushdown.
true
Whether to push predicates down into storage handlers. Ignored when hive.optimize.ppd is false.
true
Whether to transitively replicate predicate filters over equijoin conditions.
1000
How many rows in the right-most join operand Hive should buffer before emitting the join result.
25000
How many rows in the joining tables (except the streaming table) should be cached in memory.
100
How many values in each keys in the map-joined table should be cached in memory.
25000
How many rows should be cached by jdbm for map join.
false
Whether to enable skew join optimization.
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 is a skew join key.
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.
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.
nonstrict
The mode in which the hive operations are being performed. In strict mode, some risky queries are not allowed to run.
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.
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
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).
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*
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*
false
Whether to execute jobs in parallel.
8
How many jobs at most can be executed in parallel.
false
Whether to provide the row offset virtual column.
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.
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.
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.
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.
true
Merge small files at the end of a map-only job.
false
Merge small files at the end of a map-reduce job.
true
Try to generate a map-only job for merging files if CombineHiveInputFormat is supported.
256000000
Size of merged files at the end of the job.
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.
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.
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.
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.
100000
The number means after how many rows processed it needs to check the memory usage.
1000
Send a heartbeat after this interval - used by mapjoin and filter operators.
false
Whether Hive enable the optimization about converting common join into mapjoin based on the input file size.
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 TaskTracker from killing tasks with infinite loops.
org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe
The default SerDe for transmitting input data to and reading output data from the user scripts.
org.apache.hadoop.hive.ql.exec.TextRecordReader
The default record reader for reading data from the user scripts.
org.apache.hadoop.hive.ql.exec.TextRecordWriter
The default record writer for writing data to the user scripts.
org.apache.hadoop.hive.ql.io.CombineHiveInputFormat
The default input format. Set this to HiveInputFormat if you encounter problems with CombineHiveInputFormat.
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.
true
Whether speculative execution for reducers should be turned on.
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.
false
Whether bucketing is enforced. If true, while inserting into the table, bucketing is enforced.
false
Whether sorting is enforced. If true, while inserting into the table, sorting is enforced.
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.
false
Whether or not to allow dynamic partitions in DML/DDL.
strict
In strict mode, the user must specify at least one static partition in case the user accidentally overwrites all partitions.
1000
Maximum number of dynamic partitions allowed to be created in total.
100
Maximum number of dynamic partitions allowed to be created in each mapper/reducer node.
100000
Maximum number of HDFS files created by all mappers/reducers in a MapReduce job.
__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.
org.apache.hadoop.hive.serde2.DelimitedJSONSerDe
The SerDe used by FetchTask to serialize the fetch output.
false
Let hive determine whether to run in local mode automatically.
true
Do not report an error if DROP TABLE/VIEW specifies a non-existent table/view.
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.
0
How long to run autoprogressor for the script/UDTF operators (in seconds). Set to 0 for forever.
Default property values for newly created tables.
true
This enables substitution using syntax like ${var} ${system:var} and ${env:var}.
false
Whether to throw an exception if dynamic partition insert generates empty results.
hdfs,pfile
A comma separated list of acceptable URI schemes for import and export.
100000
When trying a smaller subset of data for simple LIMIT, how much size we need to guarantee each row to have at least.
10
When trying a smaller subset of data for simple LIMIT, maximum number of files we can sample.
false
Whether to enable to optimization to trying a smaller subset of data for simple LIMIT first.
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.
false
Should rework the mapred work or not. This is first introduced by SymlinkTextInputFormat to replace symlink files with real paths at compile time.
0
A number used to percentage sampling. By changing this number, user will change the subsets of data sampled.
A list of io exception handler class names. This is used to construct a list of exception handlers to handle exceptions thrown by record readers.
_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.
false
Whether to include function name in the column alias auto generated by hive.
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.
false
To cleanup the hive scratchdir while starting the hive server.
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.
false
Where to insert into multilevel directories like "insert directory '/HIVEFT25686/chinna/' from table".
0002
The dfs.umask value for the hive created folders.
true
Controls whether to connect to remote metastore server or open a new metastore server in Hive Client JVM.
As of Hive 0.10 this is no longer used. Instead if hive.metastore.uris is set then remote
mode is assumed; otherwise local.
jdbc:derby:;databaseName=metastore_db;create=true
JDBC connect string for a JDBC metastore.
org.apache.derby.jdbc.EmbeddedDriver
Driver class name for a JDBC metastore.
org.datanucleus.jdo.JDOPersistenceManagerFactory
Class implementing the JDO PersistenceManagerFactory.
true
Detaches all objects from session so that they can be used after transaction is committed.
true
Reads outside of transactions.
APP
Username to use against metastore database.
mine
Password to use against metastore database.
true
Set this to true if multiple threads access metastore through JDO concurrently.
DBCP
Uses a DBCP connection pool for JDBC metastore.
false
Validates existing schema against code. Turn this on if you want to verify existing schema.
false
Validates existing schema against code. Turn this on if you want to verify existing schema.
false
Validates existing schema against code. Turn this on if you want to verify existing schema.
rdbms
Metadata store type.
true
Creates necessary schema on a startup if one doesn't exist. set this to false, after creating it once.
checked
Throw exception if metadata tables are incorrect.
read-committed
Default transaction isolation level for identity generation.
false
Use a level 2 cache. Turn this off if metadata is changed independently of hive metastore server.
SOFT
SOFT=soft reference based cache, WEAK=weak reference based cache.
datanucleus
Name of the identifier factory to use when generating table/column names etc. 'datanucleus' is used for backward compatibility.
LOG
Defines what happens when plugin bundles are found and are duplicated EXCEPTION.
/user/hive/warehouse
Location of default database for the warehouse.
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.
List of comma separated listeners for metastore events.
List of comma separated keys occurring in table properties which will get inherited to newly created partitions. * implies all the keys will get inherited.
List of comma separated listeners for the end of metastore functions.
0
Duration after which events expire from events table (in seconds).
0
Frequency at which timer task runs to purge expired events in metastore (in seconds).
5
Number of retries while opening a connection to metastore.
1
Number of seconds for the client to wait between consecutive connection attempts.
20
MetaStore Client socket timeout in seconds.
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.
300
Maximum number of objects (tables/partitions) that can be retrieved from metastore in one batch. The higher the number, the fewer round trips are needed to the Hive metastore server, but it may also cause higher memory requirement at the client side.
Name of the hook to use for retriving the JDO connection URL. If empty, the value in javax.jdo.option.ConnectionURL is used.
1
The number of times to retry a metastore call if there were a connection error.
1000
The number of miliseconds between metastore retry attempts.
200
Minimum number of worker threads in the Thrift server's pool.
100000
Maximum number of worker threads in the Thrift server's pool.
true
Whether to enable TCP keepalive for the metastore server. Keepalive will prevent accumulation of half-open connections.
false
If true, the metastore thrift interface will be secured with SASL. Clients must authenticate with Kerberos.
The path to the Kerberos Keytab file containing the metastore thrift server's service 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.
Table,StorageDescriptor,SerDeInfo,Partition,Database,Type,FieldSchema,Order
List of comma separated metastore object types that should be pinned in the cache.
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).
false
If true, the hdfs location stored in the index file will be ignored at runtime. If the data got moved or the name of the cluster got changed, the index data should still be usable.
5368709120
Minimum size (in bytes) of the inputs on which a compact index is automatically used.
-1
Maximum size (in bytes) of the inputs on which a compact index is automatically used. A negative number is equivalent to infinity.
10737418240
The maximum number of bytes that a query using the compact index can read. Negative value is equivalent to infinity.
10000000
The maximum number of index entries to read during a query that uses the compact index. Negative value is equivalent to infinity.
true
Whether or not to use a binary search to find the entries in an index table that match the filter, where possible.
true
If 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.
jdbc:derby
The default database that stores temporary hive statistics.
true
A flag to gather statistics automatically during the INSERT OVERWRITE command.
org.apache.derby.jdbc.EmbeddedDriver
The JDBC driver for the database that stores temporary hive statistics.
jdbc:derby:;databaseName=TempStatsStore;create=true
The default connection string for the database that stores temporary hive statistics.
The Java class (implementing the StatsPublisher interface) that is used by default if hive.stats.dbclass is not JDBC or HBase.
The Java class (implementing the StatsAggregator interface) that is used by default if hive.stats.dbclass is not JDBC or HBase.
30
Timeout value (number of seconds) used by JDBC connection and statements.
0
Maximum number of retries when stats publisher/aggregator got an exception updating intermediate database. Default is no tries on failures.
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).
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.
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.
false
Enable or disable the Hive client authorization and authentication.
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.
org.apache.hadoop.hive.ql.security.HadoopDefaultAuthenticator
Hive client authenticator manager class name. The user-defined authenticator class should implement interface org.apache.hadoop.hive.ql.security.HiveAuthenticationProvider.
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 is created.
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 is created.
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 is created.
The privileges automatically granted to the owner whenever a table gets created. An example like "select,drop" will grant select and drop privileges to the owner of the table.
org.apache.hadoop.hive.ql.security.authorization.DefaultHiveMetastoreAuthorizationProvider
The 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.
A storage-based authorization implementation is provided to use as the value of this parameter:
org.apache.hadoop.hive.ql.security.authorization.StorageBasedAuthorizationProvider
which uses HDFS permissions to provide authorization instead of using Hive-style grant-based authorization.
org.apache.hadoop.hive.ql.security.HadoopDefaultMetastoreAuthenticator
The authenticator manager class name to be used in the metastore for authentication.
The user-defined authenticator class should implement interface org.apache.hadoop.hive.ql.security.HiveAuthenticationProvider.
The pre-event listener classes to be loaded on the metastore side to run code whenever databases, tables, and partitions are created, altered, or dropped. Set this parameter to org.apache.hadoop.hive.ql.security.authorization.AuthorizationPreEventListener in hive-site.xml for Hive metastore security.
org.apache.hadoop.hive.shims.HiveHarFileSystem
The implementation for accessing Hadoop Archives. Note that this won't be applicable to Hadoop versions less than 0.20.
false
Whether archiving operations are permitted.
false
In new Hadoop versions, the parent directory must be set while creating a HAR. Because this functionality is hard to detect with just version numbers, this conf var needs to be set manually.
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.
false
This parameter controls whether or not to only do lock on queries that need to execute at least one mapred job.
100
The number of times you want to try to get all the locks.
10
The number of times you want to retry to do one unlock.
60
The sleep time (in seconds) between various retries.
The list of zookeeper servers to talk to. This is only needed for read/write locks.
2181
The port of zookeeper servers to talk to. This is only needed for read/write locks.
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
The parent node under which all zookeeper nodes are created.
false
Clean extra nodes at the end of the session.
org.apache.hadoop.hive.thrift.MemoryTokenStore
The delegation token store implementation. Set to org.apache.hadoop.hive.thrift.ZooKeeperTokenStore for load-balanced cluster.
localhost:2181
The ZooKeeper token store connect string.
/hive/cluster/delegation
The root path for token store data.
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.
true
When creating a table from an input table, create the table in the input table's primary region.
default
The default region name.
The default filesystem and jobtracker for a region.
false
Whether to print the names of the columns in query output.
false
Whether to include the current database in the hive prompt.
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.
lib/hive-hwi-@VERSION@.war
This sets the path to the HWI war file, relative to ${HIVE_HOME}.
0.0.0.0
This is the host address the Hive Web Interface will listen on.
9999
This is the port the Hive Web Interface will listen on.
false
Whether hive is running in test mode. If true, it turns on sampling and prefixes the output tablename.
test_
If hive is running in test mode, prefixes the output table by this string.
32
If hive is running in test mode and table is not bucketed, sampling frequency.
If hive is running in test mode, don't sample the above comma separated list of tables.