How do I clone a hive database?
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How do I clone a hive database?
If not using the utility the following steps need to be taken to clone the database:
- Database Backups.
- Copy the backups and configs to Cluster2.
- Restore the databases on Cluster2.
- Validate that the Big SQL db is identical on the 2 clusters.
- Copy the Hive warehouse directory from Cluster1 to Cluster2.
How do I copy a table from one database to another in Hive?
To achieve this, Hive provides the options to create the table with or without data from the another table.
- Copy the data from one table to another table in Hive.
- Example : Create Table as Select in Hive.
- Copy the table structure in Hive.
- Example : Create the new table from another table without data.
Does Hive support multiple databases?
Hive supports 5 backend databases which are as follows: Derby. MySQL. MS SQL Server.
How do I change the Hive database?
By default, hive stores its data at /user/hive/warehouse on HDFS. DESCRIBE DATABASE EXTENDED student; Step 2: Use ALTER to change the parent-directory location (NOTE: /hive_db is the available directory on my HDFS ). ALTER DATABASE student SET LOCATION ‘hdfs://localhost:9000/hive_db’;
How do I partition an existing table in hive?
- Create the table with original name by running show create table on new table and replace with original table name.
- Run LOAD DATA INPATH command to move files under partitions to new partitions of new table.
- Drop the external table created.
How do I copy a Hive table from one cluster to another?
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- Install Hive on the new cluster and make sure both the source and destination clusters are identical.
- Transfer the data present in the Hive warehouse directory (/user/hive/warehouse) to the new Hadoop cluster.
- Take a backup of the Hive Metastore.
- Install MySQL on the new Hadoop cluster.
How do I partition an existing table in Hive?
How can you create and manage the database in Hive?
Go to Hive shell by giving the command sudo hive and enter the command ‘create database>’ to create the new database in the Hive. To list out the databases in Hive warehouse, enter the command ‘show databases’. The database creates in a default location of the Hive warehouse.
What is HiveQL?
The Hive Query Language (HiveQL) is a query language for Hive to process and analyze structured data in a Metastore. It filters the data using the condition and gives you a finite result. The built-in operators and functions generate an expression, which fulfils the condition.
What can be altered using alter database command in Hive?
Hadoop Hive alter database is a statement used to change the properties of a databases in Hive. You can add or remove the database comments, properties etc by using alter database statements.
How can I change my database location?
To alter the location of a table, you can run ALTER TABLE
How do I copy data from one hive cluster to another?
Also you can use the hive context and write the code in Java or Scala to copy the data. You can use Distcp command to copy the data between clusters.But you have to first convert the table data to a file and copy the file to different cluster using the command.Usage below:
How to copy the hive external table from one database to another?
1. created the external table in new databases with the same definition of the source table,but with different location. 2. Copy the CSV files of source table location to target table location. Re: Copying the Hive External table from one database to another database.
How to copy data from one Hadoop cluster to another?
You can use Distcp command to copy the data between clusters.But you have to first convert the table data to a file and copy the file to different cluster using the command.Usage below: $ hadoop distcp (src) (dest)
How do I enable partition discovery in hive for External Tables?
In external partitioned tables, this property is enabled (true) by default when you create the table using Hive in HDP 3.1.4 and later. To a legacy external table (created using an earlier version of Hive), add discover.partitions to the table properties to enable partition discovery.