Type: Bug Status: Closed. Usually, the problem does not repeat itself when trying to recreate the same tables … By default, when you drop an internal (managed) table, the data files are moved to the HDFS trashcan. The DESCRIBE statement displays metadata about a table, such as the column names and their data types. ‎02-03-2016 for deleting and updating the record from table you can use the below statements. hive> DESCRIBE financial.emp.salary salary float HIVE DROP Database … Transactional Tables: Hive supports single-table transactions. DROP TABLE removes metadata and data for this table. hive> SHOW TABLES; EMP Table1 Table2 HIVE DESCRIBE Syntax. Partitions are independent of ACID. To delete a view created by you, use the below command. If your table is text format then the table won't have any delete/update capabilities. Steps Thank you very much for the explanation regarding the work around to delete the row. It helps in reducing the complexity of a query. hive> insert into emptable partition(od) select * from emptable_tmp; Partition database… ‎01-25-2016 This command lists the tables in the current working database. Resolution: Fixed Affects Version/s: None Fix Version/s: 0.3.0. Priority: Critical . transaction manager that does not support these operations. Please anyone 48.9K views We should not delete data for external tables. This operation is expensive for tables that reside on the Amazon S3 object store. hive> alter table emptable drop partition(od='17_06_30'); Dropped the partition od=17_06_30 OK Time taken: 0.291 seconds HDFS partition deletion #hdfs dfs -rm -r /hdfs/location/emptable/ods='17_06_30' 4) Insert data for that partition only. Let's check the list of existing databases by using the following command: - This is what I did. After inserting data into a hive table will update and delete the records from created table. Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type. ‎12-07-2018 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; 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. Created Drop Database is a statement that drops all the tables and deletes the database. For example, if we need only 5 columns from a table of 50 … If the WHERE clause is specified, then it deletes the rows that satisfy the condition in where clause. Re: Can we delete data in a Hive table from spark-scala shell. For such case is there a way around to delete the rows from such tables, Created Even hive supports select and overwrite the same table at same time but any wrong queries will lead to loose data completely so it's better to use temp table in place and drop the table when we make sure the data is correct. 2. table need to be in ORC format and bucket enabled. The DELETE statement in Hive deletes the table data. 2.Take the specific partition data into temp table, 3.Overwrite the same partition by excluding the unnecessary rows, 4. once you make sure that the data is correct then drop the temp table. ‎12-12-2018 Dropping the table does not delete the data, although the metadata for the table will be deleted. SemanticException [Error 10294]: Attempt to do update or delete using This is the behavior in Hive. Partitioned Tables: Hive supports table partitioning as a means of separating data for faster writes and queries. from where ; FAILED: These are the steps we need to follow for deleting specific rows in case of non-transactional table. 12:33 AM. While running the same data step again (after deletion), i,e. Any insight would be greatly appreciated. In addition if you are having non partitioned table then we need to get full dump of existing(target) table into temp table and overwrite the target table by excluding the unnecessary rows from the temp table and most important until this process is finished make sure you are not writing any new data into target table. If its Hive Managed table, hive will delete table structure as well as data associated with hive table. Export. Proc SQL drop table -- Deletes the hive metadata but not the HDFS file. For Managed tables, Hive stores data into its warehouse directory However, after longer use I've found that fetching the data from these tables became broken: i.e., count(*) from that table estimates 2k rows, while export using beeline to csv returns >100k rows, most of which are NULL's at the end of the file. I don't think delete can be done and not supported. In Hive DB I got a table named "employee" with employee id as one field, can I set HiveContext and delete data from Hive table() like below (if not what is the best way to do) val sqlContext = new HiveContext(sc) sqlContext.sql("DELETE FROM employee WHERE employee_id=6") Thanks Can you accept best answer or provide your workaround? Note: if you had created a TABLE with EXTERNAL keyword then you can NOT remove all the rows because … 1.Then select the partition that you want to delete rows from and make sure any new data is not writing into this partition. When using proc sql - drop table / proc delete / proc dataset - delete, the hive metadata is deleted i.e. DROP: it drops the table along with the data associated with Hive Meta store. Hive - Drop Table. But drop table from Impala deletes the table metadata without deleting the files. Options. The metadata is completely lost. 3) Drop Partitions from Hive and HDFS directory as well, as this is External table. Deleting a View. NOT WORKING) 3. Created Hive>DROP TABLE guruhive_internaltable; If you dropped the guruhive_internaltable, including its metadata and its data will be deleted from Hive. Its syntax is as follows: DROP DATABASE StatementDROP (DATABASE|SCHEMA) [IF EXISTS] database_name [RESTRICT|CASCADE]; 01:36 AM. ‎12-10-2018 Hive DELETE FROM Table Alternative Apache Hive is not designed for online transaction processing and does not offer real-time queries and row level updates and deletes. In Hive DB I got a table named "employee" with employee id as one field, can I set HiveContext and delete data from Hive table() like below (if not what is the best way to do), sqlContext.sql("DELETE FROM employee WHERE employee_id=6"), Created If its external table, hive will drop table structure but not data as it is not managed by Hive but stored in specified location in HDFS. ‎12-11-2018 Can we delete data in a Hive table from spark-scal... [ANNOUNCE] New Cloudera ODBC 2.6.12 Driver for Apache Impala Released, [ANNOUNCE] New Cloudera JDBC 2.6.20 Driver for Apache Impala Released, Transition to private repositories for CDH, HDP and HDF, [ANNOUNCE] New Applied ML Research from Cloudera Fast Forward: Few-Shot Text Classification, [ANNOUNCE] New JDBC 2.6.13 Driver for Apache Hive Released. Labels: None. DROP table command in Hive With DROP command, you have the flexibility to delete the data associated with the table. This command deletes the metadata and data only, not the structure. drop table should not delete data for external tables. creating the same table in the schema - the number of records ingested is incorrect. Syntax: DELETE FROM tablename [WHERE expression]; Example: TRUNCATE. 09:33 AM. If we want to remove particular row from Hive meta store Table we use DELETE but if we want to delete all the rows from HIVE table we can use TRUNCATE. Log In. 12:42 PM. The work around for this case as follows, If your table is partitioned: 1.Then select the partition that you want to delete rows from and make sure any new data is not writing into this partition. It can update target table with a source table. 04:30 AM, Table is stored as TEXTFILE. Tables must be marked as transactional in order to support UPDATE and DELETE operations. Created For external tables, Hive assumes that it does not manage the data. How to delete hive external table data | Hadoop Interview question - YouTube. The data is actually moved to the .Trash/Current directory if Trash is configured (and PURGE is not specified). Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type. Created ‎12-07-2018 I am trying to delete some of the rows from my However, dropping the Hive table doesn't appear to delete the contents of the container. Advantages of Views. hive table which has partitions. XML Word Printable JSON. 09:56 AM. 01:05 PM. The container contains a bunch of text files. Data is sent to Trash and it can be recovered back in case of emergency. suggest why the query is not working. delete query from hive table (with partition) not working, Re: delete query from hive table (with partition) not working. Can we delete data in a Hive table from spark-scala shell. The DELETE statement can only be used on the hive tables that support ACID. I can suceessfully drop hive table in hive cli / beeline so no permission issue. If your table is text format then the table won't have any delete/update capabilities. 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. DELETE FROM test_acid WHERE key = 2; UPDATE test_acid SET value = 10 WHERE key = 3; SELECT * FROM test_acid; This example shows the most basic ways to add data into a Hive table using INSERT, UPDATE and DELETE … This behavior is because Hive by default doesn't let you drop database containing any tables. Am I correct in assuming that dropping an internal table will not remove the contents of the container because HDInsight uses Azure Blob Storage as its storage and not HDFS? Then start “hive” DROP TABLE IF EXISTS partition_test; CREATE EXTERNAL TABLE partition_test (a int ) PARTITIONED BY (p string) LOCATION '/user/hdfs/test'; INSERT OVERWRITE TABLE partition_test PARTITION (p = 'p1') SELECT FROM ; The output from the above “INSERT OVERWRITE”: Total jobs = 3 Launching Job 1 out of 3 Number of reduce tasks is set to 0 since there's no reduce … Thanks. Description. Find answers, ask questions, and share your expertise. Attachments. We often drop and recreate Hive tables with new/recalculated data under same table names. Hive facilitates us to drop a table by using the SQL drop table command. WHENs are considered different statements. When dropping an EXTERNAL table, data in the table will NOT be deleted from the file system. 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 their types. This is not an external table, but rather a managed table. Check table definition using "SHOW CREATE TABLE", to know if it satisfies above conditions. The INSERT clause generates delta_0000002_0000002_0000, containing the row … MERGE is like MySQL’s INSERT ON UPDATE. The usage of SCHEMA and DATABASE are same. So I expect: "drop table mytable" to delete both the table metadata and its contents. Details. ‎01-25-2016 Created @mohammed sarfaraz are you still having issues with this? If a managed table or partition is dropped, the data and metadata associated with that table or partition are deleted. Summary : In Data step - both in case 1 and 2 - I am not able to delete the underlying HDFS file. delete query from hive table (with partition) not ... [ANNOUNCE] New Cloudera ODBC 2.6.12 Driver for Apache Impala Released, [ANNOUNCE] New Cloudera JDBC 2.6.20 Driver for Apache Impala Released, Transition to private repositories for CDH, HDP and HDF, [ANNOUNCE] New Applied ML Research from Cloudera Fast Forward: Few-Shot Text Classification, [ANNOUNCE] New JDBC 2.6.13 Driver for Apache Hive Released. Therefore, for S3 tables, prefer to use DROP TABLE table_name PURGE rather than the default DROP TABLE statement. If you just want to delete data from Table and not hive table structure, use TRUNCATE command. Let's follow the below steps to drop the table from the database. From the following screenshot, we can observe the output . For instance: This statement will update the salary of Tom, and insert a new row of Mary. Let us practice all the above mentioned one by one. You can create a new table without employee_id=6, Created When you drop a table from Hive Metastore, it removes the table/column data and their metadata. 01:34 AM. delete Code: DROP VIEW IF EXISTS English_class; DROP TABLE command cannot be used to drop a view if the EXISTS clause works similarly for tables. (NOT WORKING) Note : In all the above cases, skipTrash is set in hive library. It is not in ORC format or bucket enable. Drop Database Statement. Given below are the advantages expressed. By default, Hive is in RESTRICT mode and if you want to drop a database with tables, then you'll have to use the CASCADE mode. Hadoop Flags: Reviewed. table structure is dropped from the schema but the underlying HDFS file is not. Component/s: Query Processor. This chapter describes how to drop a database in Hive. Re: delete query from hive table (with partition) not working. However, the latest version of Apache Hive supports ACID transaction, but using ACID transaction on table with huge amount of data may kill the performance of Hive server. There are two modes of dropping databases in Hive: RESTRICT and CASCADE. Find answers, ask questions, and share your expertise.