Org.apache.hadoop jar file download
Hue connects to any database or warehouse via native Thrift or SqlAlchemy connectors that need to be added to the Hue ini file. Except [impala] and [beeswax] which have a dedicated section, all the other ones should be appended below the [[interpreters]] of [notebook] e. Most of the interpreters require to install their SqlAlchemy dialect e. Read about how to build your own parser if you are looking at better autocompletes for your the SQL dialects you use.
This feature requires Editor v2 and is quite functional despite not being offically released and on by default. NOTE: After enabling the above flags, if a django. The Dev Onboarding documentation demoes the integration.
Note For historical reason, the name of the configuration section is [beeswax]. Requires support for sending multiple queries when using Tez instead of a maximum of just one at the time. You can turn it on with this setting:. When the LLAP interpreter is added, there are 2 ways to enable connectivity direct configuration or service discovery.
LLAP is added by enabling the following settings:. In order to prevent spamming zookeeper, HiveServer2 is cached for the life of the process and llap is cached based on the following setting:. Install at least the 0. Note : keep [[[presto]]] if not using the connectors. Note In the past Hue did not use trino specific dialect of SQLAlchemy which may lead to a catalog must be specified error.
This can be solved by setting protocol. Please note that our input data is in the below format where Country is at 7 th index, with 0 as a starting index -. In this section, we will understand the implementation of SalesCountryReducer class. We begin by specifying a name of the package for our class. SalesCountry is a name of out package.
Please note that output of compilation, SalesCountryReducer. This output of mapper becomes input to the reducer. So, to align with its data type, Text and IntWritable are used as data type here.
Every reducer class must be extended from MapReduceBase class and it must implement Reducer interface. Do not rely on internal build tool logic Apr 26, Nov 9, Setting java boot classpath so that scala 2. Nov 8, Upgrade Hadoop and Hive to version 3 Apr 20, Closing RestRepository to avoid a connection leak May 8, Cross compile Scala code using Gradle variants Nov 2, Allow the usage of a local repositry when building the project. Pull …. Feb 21, Jul 17, Oct 27, Update Gradle wrapper to version 6.
Jan 13, Sqoop can also import the result set of an arbitrary SQL query. Instead of using the --table , --columns and --where arguments, you can specify a SQL statement with the --query argument. When importing a free-form query, you must specify a destination directory with --target-dir. If you want to import the results of a query in parallel, then each map task will need to execute a copy of the query, with results partitioned by bounding conditions inferred by Sqoop.
You must also select a splitting column with --split-by. Alternately, the query can be executed once and imported serially, by specifying a single map task with -m 1 :. The facility of using free-form query in the current version of Sqoop is limited to simple queries where there are no ambiguous projections and no OR conditions in the WHERE clause.
Use of complex queries such as queries that have sub-queries or joins leading to ambiguous projections can lead to unexpected results. Sqoop imports data in parallel from most database sources. You can specify the number of map tasks parallel processes to use to perform the import by using the -m or --num-mappers argument.
Each of these arguments takes an integer value which corresponds to the degree of parallelism to employ. By default, four tasks are used. Some databases may see improved performance by increasing this value to 8 or Do not increase the degree of parallelism greater than that available within your MapReduce cluster; tasks will run serially and will likely increase the amount of time required to perform the import. Likewise, do not increase the degree of parallism higher than that which your database can reasonably support.
Connecting concurrent clients to your database may increase the load on the database server to a point where performance suffers as a result. When performing parallel imports, Sqoop needs a criterion by which it can split the workload. Sqoop uses a splitting column to split the workload. By default, Sqoop will identify the primary key column if present in a table and use it as the splitting column. The low and high values for the splitting column are retrieved from the database, and the map tasks operate on evenly-sized components of the total range.
If the actual values for the primary key are not uniformly distributed across its range, then this can result in unbalanced tasks. You should explicitly choose a different column with the --split-by argument. Sqoop cannot currently split on multi-column indices. If your table has no index column, or has a multi-column key, then you must also manually choose a splitting column.
The option --autoreset-to-one-mapper is typically used with the import-all-tables tool to automatically handle tables without a primary key in a schema. When launched by Oozie this is unnecessary since Oozie use its own Sqoop share lib which keeps Sqoop dependencies in the distributed cache. Oozie will do the localization on each worker node for the Sqoop dependencies only once during the first Sqoop job and reuse the jars on worker node for subsquencial jobs.
By default, the import process will use JDBC which provides a reasonable cross-vendor import channel. Some databases can perform imports in a more high-performance fashion by using database-specific data movement tools. By supplying the --direct argument, you are specifying that Sqoop should attempt the direct import channel. This channel may be higher performance than using JDBC. By default, Sqoop will import a table named foo to a directory named foo inside your home directory in HDFS.
You can adjust the parent directory of the import with the --warehouse-dir argument. When using direct mode, you can specify additional arguments which should be passed to the underlying tool. If the argument -- is given on the command-line, then subsequent arguments are sent directly to the underlying tool. For example, the following adjusts the character set used by mysqldump :. By default, imports go to a new target location.
If you use the --append argument, Sqoop will import data to a temporary directory and then rename the files into the normal target directory in a manner that does not conflict with existing filenames in that directory.
By default, Sqoop uses the read committed transaction isolation in the mappers to import data. This may not be the ideal in all ETL workflows and it may desired to reduce the isolation guarantees. The --relaxed-isolation option can be used to instruct Sqoop to use read uncommitted isolation level.
The read-uncommitted isolation level is not supported on all databases for example, Oracle , so specifying the option --relaxed-isolation may not be supported on all databases. However the default mapping might not be suitable for everyone and might be overridden by --map-column-java for changing mapping to Java or --map-column-hive for changing Hive mapping.
Sqoop provides an incremental import mode which can be used to retrieve only rows newer than some previously-imported set of rows. Sqoop supports two types of incremental imports: append and lastmodified. You can use the --incremental argument to specify the type of incremental import to perform. You should specify append mode when importing a table where new rows are continually being added with increasing row id values.
Sqoop imports rows where the check column has a value greater than the one specified with --last-value. An alternate table update strategy supported by Sqoop is called lastmodified mode. You should use this when rows of the source table may be updated, and each such update will set the value of a last-modified column to the current timestamp.
Rows where the check column holds a timestamp more recent than the timestamp specified with --last-value are imported. At the end of an incremental import, the value which should be specified as --last-value for a subsequent import is printed to the screen.
When running a subsequent import, you should specify --last-value in this way to ensure you import only the new or updated data. This is handled automatically by creating an incremental import as a saved job, which is the preferred mechanism for performing a recurring incremental import. See the section on saved jobs later in this document for more information. Delimited text is the default import format. You can also specify it explicitly by using the --as-textfile argument.
This argument will write string-based representations of each record to the output files, with delimiter characters between individual columns and rows.
These delimiters may be commas, tabs, or other characters. The delimiters can be selected; see "Output line formatting arguments. Delimited text is appropriate for most non-binary data types. It also readily supports further manipulation by other tools, such as Hive. SequenceFiles are a binary format that store individual records in custom record-specific data types.
These data types are manifested as Java classes. Sqoop will automatically generate these data types for you. This format supports exact storage of all data in binary representations, and is appropriate for storing binary data for example, VARBINARY columns , or data that will be principly manipulated by custom MapReduce programs reading from SequenceFiles is higher-performance than reading from text files, as records do not need to be parsed.
Avro data files are a compact, efficient binary format that provides interoperability with applications written in other programming languages. Avro also supports versioning, so that when, e.
By default, data is not compressed. You can compress your data by using the deflate gzip algorithm with the -z or --compress argument, or specify any Hadoop compression codec using the --compression-codec argument. This applies to SequenceFile, text, and Avro files. If this data is truly large, then these columns should not be fully materialized in memory for manipulation, as most columns are.
Instead, their data is handled in a streaming fashion. Large objects can be stored inline with the rest of the data, in which case they are fully materialized in memory on every access, or they can be stored in a secondary storage file linked to the primary data storage.
By default, large objects less than 16 MB in size are stored inline with the rest of the data. The size at which lobs spill into separate files is controlled by the --inline-lob-limit argument, which takes a parameter specifying the largest lob size to keep inline, in bytes. If you set the inline LOB limit to 0, all large objects will be placed in external storage. When importing to delimited files, the choice of delimiter is important.
Delimiters which appear inside string-based fields may cause ambiguous parsing of the imported data by subsequent analysis passes. For example, the string "Hello, pleased to meet you" should not be imported with the end-of-field delimiter set to a comma.
Supported escape characters are:. For unambiguous parsing, both must be enabled. For example, via --mysql-delimiters. If unambiguous delimiters cannot be presented, then use enclosing and escaping characters. The combination of optional enclosing and escaping characters will allow unambiguous parsing of lines. For example, suppose one column of a dataset contained the following values:.
Note that to prevent the shell from mangling the enclosing character, we have enclosed that argument itself in single-quotes. Here the imported strings are shown in the context of additional columns "1","2","3" , etc. The enclosing character is only strictly necessary when delimiter characters appear in the imported text.
The enclosing character can therefore be specified as optional:. Even though Hive supports escaping characters, it does not handle escaping of new-line character. Also, it does not support the notion of enclosing characters that may include field delimiters in the enclosed string. The --mysql-delimiters argument is a shorthand argument which uses the default delimiters for the mysqldump program.
If you use the mysqldump delimiters in conjunction with a direct-mode import with --direct , very fast imports can be achieved. While the choice of delimiters is most important for a text-mode import, it is still relevant if you import to SequenceFiles with --as-sequencefile. The generated class' toString method will use the delimiters you specify, so subsequent formatting of the output data will rely on the delimiters you choose.
When Sqoop imports data to HDFS, it generates a Java class which can reinterpret the text files that it creates when doing a delimited-format import. The delimiters are chosen with arguments such as --fields-terminated-by ; this controls both how the data is written to disk, and how the generated parse method reinterprets this data. The delimiters used by the parse method can be chosen independently of the output arguments, by using --input-fields-terminated-by , and so on. This is useful, for example, to generate classes which can parse records created with one set of delimiters, and emit the records to a different set of files using a separate set of delimiters.
Importing data into Hive is as simple as adding the --hive-import option to your Sqoop command line. If the Hive table already exists, you can specify the --hive-overwrite option to indicate that existing table in hive must be replaced. The script will be executed by calling the installed copy of hive on the machine where Sqoop is run. This function is incompatible with --as-avrodatafile and --as-sequencefile.
If you do use --escaped-by , --enclosed-by , or --optionally-enclosed-by when importing data into Hive, Sqoop will print a warning message. You can use the --hive-drop-import-delims option to drop those characters on import to give Hive-compatible text data. Alternatively, you can use the --hive-delims-replacement option to replace those characters with a user-defined string on import to give Hive-compatible text data.
Sqoop will pass the field and record delimiters through to Hive. Sqoop will by default import NULL values as string null. You should append parameters --null-string and --null-non-string in case of import job or --input-null-string and --input-null-non-string in case of an export job if you wish to properly preserve NULL values. The table name used in Hive is, by default, the same as that of the source table. You can control the output table name with the --hive-table option.
Hive can put data into partitions for more efficient query performance. You can tell a Sqoop job to import data for Hive into a particular partition by specifying the --hive-partition-key and --hive-partition-value arguments.
The partition value must be a string. Please see the Hive documentation for more details on partitioning. You can import compressed tables into Hive using the --compress and --compression-codec options. One downside to compressing tables imported into Hive is that many codecs cannot be split for processing by parallel map tasks.
The lzop codec, however, does support splitting. When importing tables with this codec, Sqoop will automatically index the files for splitting and configuring a new Hive table with the correct InputFormat. This feature currently requires that all partitions of a table be compressed with the lzop codec.
Sqoop can also import records into a table in HBase. Sqoop will import data to the table specified as the argument to --hbase-table. Each row of the input table will be transformed into an HBase Put operation to a row of the output table. The key for each row is taken from a column of the input. By default Sqoop will use the split-by column as the row key column. If that is not specified, it will try to identify the primary key column, if any, of the source table.
You can manually specify the row key column with --hbase-row-key. Each output column will be placed in the same column family, which must be specified with --column-family. This function is incompatible with direct import parameter --direct. If the input table has composite key, the --hbase-row-key must be in the form of a comma-separated list of composite key attributes. In this case, the row key for HBase row will be generated by combining values of composite key attributes using underscore as a separator.
NOTE: Sqoop import for a table with composite key will work only if parameter --hbase-row-key has been specified. If the target table and column family do not exist, the Sqoop job will exit with an error. You should create the target table and column family before running an import. If you specify --hbase-create-table , Sqoop will create the target table and column family if they do not exist, using the default parameters from your HBase configuration. Sqoop currently serializes all values to HBase by converting each field to its string representation as if you were importing to HDFS in text mode , and then inserts the UTF-8 bytes of this string in the target cell.
Sqoop will skip all rows containing null values in all columns except the row key column. To decrease the load on hbase, Sqoop can do bulk loading as opposed to direct writes. To use bulk loading, enable it using --hbase-bulkload. Sqoop will import data to the table specified as the argument to --accumulo-table.
Each row of the input table will be transformed into an Accumulo Mutation operation to a row of the output table. You can manually specify the row key column with --accumulo-row-key. Each output column will be placed in the same column family, which must be specified with --accumulo-column-family. This function is incompatible with direct import parameter --direct , and cannot be used in the same operation as an HBase import.
If the target table does not exist, the Sqoop job will exit with an error, unless the --accumulo-create-table parameter is specified. Otherwise, you should create the target table before running an import. Sqoop currently serializes all values to Accumulo by converting each field to its string representation as if you were importing to HDFS in text mode , and then inserts the UTF-8 bytes of this string in the target cell.
By default, no visibility is applied to the resulting cells in Accumulo, so the data will be visible to any Accumulo user. Use the --accumulo-visibility parameter to specify a visibility token to apply to all rows in the import job. In order to connect to an Accumulo instance, you must specify the location of a Zookeeper ensemble using the --accumulo-zookeepers parameter, the name of the Accumulo instance --accumulo-instance , and the username and password to connect with --accumulo-user and --accumulo-password respectively.
As mentioned earlier, a byproduct of importing a table to HDFS is a class which can manipulate the imported data. Therefore, you should use this class in your subsequent MapReduce processing of the data. The class is typically named after the table; a table named foo will generate a class named foo.
You may want to override this class name. Similarly, you can specify just the package name with --package-name. The following import generates a class named com. SomeTable :. You can control the output directory with --outdir. The import process compiles the source into.
You can select an alternate target directory with --bindir. If you already have a compiled class that can be used to perform the import and want to suppress the code-generation aspect of the import process, you can use an existing jar and class by providing the --jar-file and --class-name options.
This command will load the SomeTableType class out of mydatatypes. Properties can be specified the same as in Hadoop configuration files, for example:. Storing data in SequenceFiles, and setting the generated class name to com. Employee :. Performing an incremental import of new data, after having already imported the first , rows of a table:. Data from each table is stored in a separate directory in HDFS.
For the import-all-tables tool to be useful, the following conditions must be met:. Although the Hadoop generic arguments must preceed any import arguments, the import arguments can be entered in any order with respect to one another.
These arguments behave in the same manner as they do when used for the sqoop-import tool, but the --table , --split-by , --columns , and --where arguments are invalid for sqoop-import-all-tables. The import-all-tables tool does not support the --class-name argument. You may, however, specify a package with --package-name in which all generated classes will be placed. A PDS is akin to a directory on the open systems. The records in a dataset can contain only character data.
Records will be stored with the entire record as a single text field. Sqoop is designed to import mainframe datasets into HDFS. To do so, you must specify a mainframe host name in the Sqoop --connect argument. You might need to authenticate against the mainframe host to access it.
You can use the --username to supply a username to the mainframe. Sqoop provides couple of different ways to supply a password, secure and non-secure, to the mainframe which is detailed below. Secure way of supplying password to the mainframe. You can use the --dataset argument to specify a partitioned dataset name.
All sequential datasets in the partitioned dataset will be imported. Sqoop imports data in parallel by making multiple ftp connections to the mainframe to transfer multiple files simultaneously. You can adjust this value to maximize the data transfer rate from the mainframe.
By default, Sqoop will import all sequential files in a partitioned dataset pds to a directory named pds inside your home directory in HDFS.
By default, each record in a dataset is stored as a text record with a newline at the end. Since mainframe record contains only one field, importing to delimited files will not contain any field delimiter.
However, the field may be enclosed with enclosing character or escaped by an escaping character. You should use this class in your subsequent MapReduce processing of the data. The class is typically named after the partitioned dataset name; a partitioned dataset named foo will generate a class named foo. SomePDS :. The target table must already exist in the database. The input files are read and parsed into a set of records according to the user-specified delimiters. The default operation is to transform these into a set of INSERT statements that inject the records into the database.
In "update mode," Sqoop will generate UPDATE statements that replace existing records in the database, and in "call mode" Sqoop will make a stored procedure call for each record. Although the Hadoop generic arguments must preceed any export arguments, the export arguments can be entered in any order with respect to one another.
Table The --export-dir argument and one of --table or --call are required. Ethical Hacking. Computer Graphics. Software Engineering. Web Technology. Cyber Security. C Programming. Control System. Data Mining. Data Warehouse.
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