PURGE clause: 2. Hive Drop Table - The DROP TABLE statement is used to drop an existing table in a database.The SQL DROP TABLE statement allows you to remove or delete a table from the SQL database. In above code and from screen shot we do following things, boolean: functionExists (String db ... Returns the user name which is used as owner for Hive table. A Computer Science portal for geeks. Hive will remove all of its data and metadata from the hive meta-store. Hive has a Internal and External tables. Students not answering emails about plagiarism. If the table is external table then only the metadata is dropped. 1. © Copyright 2018-2020 www.madanswer.com. See the full job below. External table files can be accessed and managed by processes outside of Hive. In Hive, there is an option to use purge in the drop table command. How can I use GDAL installed with QGIS from command line? What do you roll to sleep in a hidden spot? Hive support for PURGE was added in 0.14 (for tables) and 1.2 (for partitions), so the code reflects that: trying to use the option with older versions of Hive will … The usage of SCHEMA and DATABASE are same. In case of external table as well, Drop table command removes metadata and data of a table, but from only Hive table, data will be still present in HDFS location, as external table’s data is completely managed by HDFS itself, so only the linkage between Hive … So it cannot be retrieved in case of an accidental DROP statement. Can a Lan Adapter cause a whole home network to crash? For non-Hive tables and partitions, Spark already behaves as if the PURGE option was set, so there's no need to do anything. Translation of lucis mortiat / reginae gloriae. Why might radios not be effective in a post-apocalyptic world? 1. In SAS, when using sql pass through, purge option can be used but what if the user uses proc sql / data step ? Q: How does OVERWRITE clause work in CREATE TABLE statement in Hive. I hope your day is going well. Hive Drop,Truncate&Alter这里主要介绍除create语句外两种常用的语句， Drop,Truncate和Alter。Drop,TruncateDROP TABLE [IF EXISTS] table_name [PURGE];DROP TABLE命令将会删除这个表的元数据和数据，如果是内部表且配置了Trash并且PURGE没有指定数据将会被移动到当前目录 In "By her own quick-wittedness and adroitness she had turned the tables on her would-be destroyer". DROP TABLE command in the hive is used to drop a table inside the hive. DROP TABLE IF EXISTS hql.customer PURGE; Underlying data in HDFS will be purged directly and table cannot be restored. creating the same table in the schema - the number of records ingested is incorrect. Click here to read more about Loan/Mortgage, Many hands make light work, Share it here, Q: Which of the following is true about drop command in Hive. In case of an external table, only the associated metadata information is removed from the metastore database. When you drop a table from Hive Metastore, it removes the table/column data and their metadata. Use the PURGE clause of DROP TABLE when dropping internal (managed) tables. From the following screenshot, we can observe the output . What is the use of PURGE in DROP statement of Hive? 前言 语法:DROP TABLE [IF EXISTS] table_name [PURGE]; -- (Note: PURGE available in Hive 0.14.0 and later) 删除此表的元数据和数据。如果配置了Trash (没有指定 PURGE)，数据实际上会移动到 .Trash/Current 目录。元数据完全丢失。 In SAS, when using sql pass through, purge option can be used but what if the user uses proc sql / data step ? What is the use of PURGE in DROP statement of Hive? Is there a good alternative word to “performance” to describe a music team's actions? Using %sql or spark.sql to drop table doesn’t work either. When I have a table at my sqoop schema and want to delete it, I go to HIVE editor (through HUE) and key in the following command DROP TABLE IF EXISTS schemaName.tblName PURGE;. Syntax: DROP TABLE [IF EXISTS] table_name [PURGE]; Example: DROP TABLE IF EXISTS hql.customer; Underlying data of this internal table will be moved to Trash folder. If PURGE is not specified then the data is actually moved to the .Trash/current directory. This option is used by Hive to directly delete the files instead of moving them to the trash. The drop partition will actually move data to the .Trash/Current directory if Trash is configured, unless PURGE is specified, but the metadata is completely lost. When I have a table at my sqoop schema and want to delete it, I go to HIVE editor (through HUE) and key in the following command DROP TABLE IF EXISTS schemaName.tblName PURGE;. When you drop a Hive table all the metadata information related to the table is dropped. When you run DROP TABLE on an external table, by default Hive drops only the metadata (schema). Next steps? If the client supports it (Hive >= 0.14.0 according to the Hive docs), we should allow that option to be defined. We use PURGE option when we are absolutely sure to delete the data of a table. With DROP TABLE tableName PURGE statement, table data will not go to trash folder. Q: What is the use of .hiverc file in Hive? We use PURGE option when we are absolutely sure to delete the data of a table. For non-Hive tables and partitions, Spark already behaves as if the PURGE option was set, so there's no need to do anything. Why couldn't Foaly tell that Artemis had planned more than what he let on under the effect of the Mesmer while he was editing Artemis's memories? How worried should I be about this cough? Load the data into internal table Hive>LOAD DATA INPATH '/user/guru99hive/data.txt' INTO table guruhive_internaltable; 3. Cause. After that the table disappeared form the gui of HUE (sqoop table list, metastore list) but the actual files of the table were not deleted from the HDFS. An exception is thrown if the table does not exist. What is the use of PURGE in DROP statement of Hive? Drop Database Statement. Q: What is the use of strict mode in Hive? Do Master Records (in a Master-detail Relationship) Get Locked? After that the table disappeared form the gui of HUE (sqoop table list, metastore list) but the actual files of the table were not deleted from the HDFS. If you want the DROP TABLE command to also remove the actual data in the external table, as DROP TABLE does on a managed table, you need to configure the table properties accordingly. Drop the specified table. When you drop a table from Hive Metastore, it removes the table/column data and their metadata. When you drop a range-, hash-, or list-partitioned table, then the database drops all the table partitions. cwiki.apache.org/confluence/display/Hive/LanguageManual+DDL, State of the Stack: a new quarterly update on community and product, Podcast 320: Covid vaccine websites are frustrating. 1.- A table called "Test" is created by a sqoop import job using "--create-hcatalog-table". Making statements based on opinion; back them up with references or personal experience. For non-Hive tables and partitions, Spark already behaves as if the PURGE option was set, so there's no need to do anything. How to initialize a qubit with a custom state in Qiskit Composer. jdbc:hive2://127.0.0.1:10000 > ALTER TABLE zipcodes DROP IF EXISTS PARTITION ( … What is the difference between quit and exit in hive. ALTER TABLE some_table DROP IF EXISTS PARTITION(year = 2012); This command will remove the data and metadata for this partition. To drop the internal table Hive>DROP TABLE guruhive_internaltable; Click here to read more about Loan/Mortgage. The DROP TABLE statement in Hive deletes the data for a particular table and remove all metadata associated with it from Hive metastore. But if you do use purge table won't go to Trash directory, so it can't be recovered. With DROP TABLE tableName PURGE statement, table data will not go to trash folder. By default, when you drop an internal (managed) table, the data files are moved to the HDFS trashcan. site design / logo © 2021 Stack Exchange Inc; user contributions licensed under cc by-sa. When using proc sql - drop table / proc delete / proc dataset - delete, the hive metadata is deleted i.e. It can be a normal table (stored in Metastore) or an external table (stored in local file system); Hive treats both in the same manner, irrespective of … Related Articles Hadoop Hive Table Dynamic Partition and Examples 4. When dropping an external table with its data located in an encryption zone, hive should not throw out MetaException(message:Unable to drop table because it is in an encryption zone and trash is enabled. When you run Drop table command, Spark checks whether table exists or not before dropping the table. ALTER TABLE table_name DROP [IF EXISTS] PARTITION partition_spec PURGE; -- (Note: Hive 1.2.0 and later) PURGE选项也可以用表属性中auto.purge指定（见上文的TBLPROPERTIES）。 从Hive0.7.0到更高版本，DROP的分区如果不存在，返回一个错误，除非指定IF EXISTS或设置变量hive.exec.drop.ignorenonexistent为true。 What is the difference between partitioning and bucketing a table in Hive ? That flag is necessary in certain situations where the table data cannot be moved to the trash (which will be tried unless "PURGE" is requested).