How do I drop an external hive table without data?
The goal is to destroy a Hive schema but keep the data underneath. Given a Hive external table, created for example with script 1, it can be dropped with script 2. This deletes the data (removes the folder /user/me/data/ ).
How do you drop an external table in hive with data?
Drop an external table along with data
- Create a CSV file of data you want to query in Hive.
- Start Hive.
- Run DROP TABLE on the external table. DROP TABLE names_text;
- Prevent data in external table from being deleted by a DROP TABLE statement. ALTER TABLE addresses_text SET TBLPROPERTIES (‘external.table.purge’=’false’);
Which of the following command is used to drop the table in hive?
Introduction to Hive DDL commands
|DDL Command||Use With|
How do I drop a partition in hive?
Drop or Delete Hive Partition You can use ALTER TABLE with DROP PARTITION option to drop a partition for a table. ALTER TABLE some_table DROP IF EXISTS PARTITION(year = 2012); This command will remove the data and metadata for this partition.
What happens when you drop and an external table in Hive?
External tables are stored outside the warehouse directory. They can access data stored in sources such as remote HDFS locations or Azure Storage Volumes. Whenever we drop the external table, then only the metadata associated with the table will get deleted, the table data remains untouched by Hive.
What happens if we drop external table?
Dropping an external table removes all table-related metadata. It doesn’t delete the external data.
How many types of partitions can be applied in the Hive?
If we take state column as partition key and perform partitions on that India data as a whole, we can able to get Number of partitions (38 partitions) which is equal to number of states (38) present in India. Such that each state data can be viewed separately in partitions tables.
In which mode HiveServer2 accepts just real thrift calls in Hive?
In remote mode HiveServer2 only accepts valid Thrift calls – even in HTTP mode, the message body contains Thrift payloads.
How many types of partitions can be applied in the hive?
How do I drop all tables in a hive database?
To drop the tables in the database as well, use DROP DATABASE … with CASCADE option.
- Drop database without table or Empty Database: hive> DROP DATABASE database_name;
- Drop database with tables: hive> DROP DATABASE database_name CASCADE; It dropping respective tables before dropping the database.
How do I recover a deleted partition in Hive?
ALTER TABLE RECOVER PARTITIONS is the command that is widely used in Hive to refresh partitions as new partitions are directly added to the file system by other users. Qubole has added path validation to the ALTER TABLE RECOVER PARTITIONS command. The command only recovers valid paths.
Does dropping partition delete data?
DROP PARTITION command deletes a partition and any data stored on that partition. DROP PARTITION command can drop partitions of a LIST or RANGE partitioned table; please note that this command does not work on a HASH partitioned table.
Why does hive not let you drop a database?
This behavior is because Hive by default doesn’t let you drop database containing any tables. There are two modes of dropping databases in Hive: RESTRICT and CASCADE. 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.
How do you Drop a table in hive?
CASCADE – Use CASCADE option, if you wanted to drop all tables before dropping the database. Below are some of the most used Hive DROP DATABASE commands. The Below example drops emp database. In case if specified database not present, Hive returns an error.
What are the optional clauses in hive drop table?
Hive DROP DATABASE consists of several optional clauses, using these we can change the behavior of the Hive statements. IF EXISTS – Use IF EXISTS to check if the database exists before running a drop database statement. RESTRICT – The default behavior is RESTRICT, where DROP DATABASE will fail if the database is not empty.
Can you use databse and schema in hive?
DATABSE and SCHEMA can be used interchangeably in Hive as both refer to the same. In this article, I am using DATABASE but you can use SCHEMA instead. Below example drops an employee table from Hive metastore. If the table exists in a database, specify the database name.